CN102405205A

CN102405205A - Process for preparing alkyl levulinates

Info

Publication number: CN102405205A
Application number: CN2010800172243A
Authority: CN
Inventors: F·荆; S·多南; S·萨利富诺; B·木兰
Original assignee: Segetis Inc
Current assignee: Segetis Inc
Priority date: 2009-03-05
Filing date: 2010-03-05
Publication date: 2012-04-04
Also published as: EP2403821A2; WO2010102203A2; WO2010102203A3

Abstract

A process for converting furfuryl alcohol to a levulinic acid ester in a single step reaction, comprising adding the product levulinic acid ester to a reaction mixture of alkyl alcohol and furfuryl alcohol in the presence of a strong albumin acid catalyst, wherein a high yield of the levulinic acid ester is achieved by a small amount of tar residue that does not precipitate or solidify in the reaction mixture.

Description

The method for preparing the levulinic acid alkyl ester

This application is submitted on March 5th, 2010 and is the pct international patent application; Name is the Segetis of U.S. domestic enterprise; Inc., this application people specifies the All Countries except the U.S., and citizen of the People's Republic of China Feng Jing, United States citizen Steven Donen, United States citizen Sergey Selifonov and United States citizen Brian Mullen; The applicant only specifies the U.S.; And require the right of priority of the U.S. Patent Application Serial Number 61/157,746 that is entitled as " Method For The Preparation Of Alkyl Levulinates " of submission on March 5th, 2009, it is incorporated herein by reference.

Technical field

The disclosure relates to the method for preparing levulinate from furfuryl alcohol.

Background technology

Knownly prepare levulinic acid and levulinate from furfuryl alcohol.

United States Patent(USP) No. 2,738,367 disclose a kind of method for preparing levulinic acid, are included in strong-acid ion exchange resin and have the aqueous solution of heating furfuryl alcohol under 30 ℃ to 100 ℃ temperature down.Zeo-karb comprises AMBERLITE IR-120 and AMBERLITE IR-105.Use this technology to be unrealized synthesizing of levulinate, and will need other step.

United States Patent(USP) No. 5; 175; 358 disclose a kind of method for preparing levulinic acid, and the existence that is included in water and strong protonic acid is the heating furfuryl alcohol down, and comprise and set up reaction medium; Contain water, said strong protonic acid and play the levulinic acid of the amount of reaction solvent effect, and said furfuryl alcohol is added in this reaction medium progressively.Yet the acid of only giving an example in this patent is hydrochloric acid and Hydrogen bromide.In addition, use this technology to be unrealized synthesizing of levulinate, and will need other step.

English Patent No.GB 1,283, and 185 disclose a kind of method for preparing levulinic acid, is included under the existence of water-soluble fatty ketone solvent in water, to heat furfuryl alcohol together with hydrochloric acid or oxalic acid.Use this technology to be unrealized synthesizing of levulinate, and will need other step.

Japanese Patent No.JP 07000581B discloses and has passed through at H ₂In the presence of non-oxide mineral acid (for example HCl), heat furfuryl alcohol in the mixture of O and organic acid (for example acetate) and prepare levulinic acid.Use this technology to be unrealized synthesizing of levulinate, and will need other step.

United States Patent(USP) No. 2,763,665 have described a kind of method for preparing levulinate, be included in 64 ℃-220 ℃ temperature, in anhydrous basically condition, exist under hydrochloric acid or the hydrobromic condition and slowly to add the furfuryl alcohol and second alcohol.In order to realize tangible yield, this method requires the interpolation speed of control furfuryl alcohol, makes the amount of the unreacted furfuryl alcohol that exists in the reaction mixture never greater than the 2vol% of the volume of second alcohol.In order in reaction mixture, to keep the aspiration level of furfuryl alcohol, use at least 4 moles excessive second alcohol of every mole of furfuryl alcohol.This excessive alcohol must distill from reaction mixture then.

United States Patent(USP) No. 3,203,964 have described a kind of method for preparing levulinate, and it is intended to improve United States Patent(USP) No. 2,763, the method in 665 (above-mentioned).This improvement is included in water and exists down and carries out preceding method, and the amount of the water of use is greater than about 0.5% and be no more than said second pure about 4 weight % basically.The existence of water plays a role avoiding forming alkyl chloride, otherwise it forms from second alcohol in the anhydrous process of using United States Patent(USP) No. 2,763,665.In this prior art, because second alcohol is converted into alkyl halide, the significantly sacrificing of catalytic activity loses.According to the method for this method, alkyl halide can not recycle in reaction in the future.

United States Patent(USP) No. 4,236,021 discloses in the presence of strong acid catalyst the method for the purifying of the levulinate that the reaction through furfuryl alcohol and unsubstituted uncle or secondary aliphatics or alicyclic ring alcohol prepares.Thick levulinate is collected the high boiling solvent of at least 3 volume % of levulinate, this solvent through vacuum distilling from mixture: (a) boiling point is than at least 20 ℃ of the boiling point height of levulinate; (b) dissolving by-product polymer tar; And it is (c) miscible with levulinate.These solvents comprise glycerol acetate, dimethyl phthalate, phthalic acid di tert butyl carbonate, and diethyl phthalate.

United States Patent(USP) No. 7; 265; 239 disclose the method that furfuryl alcohol is converted into levulinic acid or levulinate, comprise making chaff alcohol and water or alkyl alcohol contact porous heterogeneous catalyst (comprising strong acid ion-exchange resin), and wherein the average pore diameter in the hole of this catalyzer is 1 to 1000nm.

Russ P No.RU 2319690 discloses through (having ferric acetyl acetonade [Fe (acac) in the poisonous chlorinated solvent at tetracol phenixin ₃] make furfuryl alcohol and fatty alcohol react the method for preparing levulinate under the condition as catalyzer.Reactive component [Fe (acac) ₃]: [furfuryl alcohol]: [fatty alcohol]: [CCl ₄] respectively with mol ratio 1: (50-200): (100-400): (100-400) exist, and make under the boiling point that is reflected at alcohol and carry out 2-5h.The yield of open levulinate is 80-98%.

Need provide a kind of in the industry and prepare the method for levulinate from furfuryl alcohol, it provides high yield in one-step synthesis.Need provide a kind of in the industry and prepare the method for levulinate from furfuryl alcohol, it does not cause tar residue from reaction mixture, to be separated out in reaction process, thereby is provided for the simple and easy synthetic and suitability of continuation method.Need provide a kind of in the industry and prepare the method for levulinate from furfuryl alcohol, it avoids the use of stainless steel is produced corrosive protic acid catalyzer (for example hydrochloric acid), thereby avoids the unnecessary cost relevant with specific installation.Need provide a kind of in the industry and prepare the method for levulinate from furfuryl alcohol, for security purpose with avoid because the corrosion that vapor phase acid produces, it uses for example hydrochloric acid of non-volatile protic acid catalyzer.Need provide a kind of in the industry and prepare the method for levulinate from furfuryl alcohol, it neither needs also not form for example chlorinated cpds of toxic materials.Need provide a kind of in the industry and prepare the method for levulinate from furfuryl alcohol, it does not need a large amount of excessive reagent, thereby eliminates circulation and avoid by product to form.Need provide a kind of in the industry and prepare the method for levulinate from furfuryl alcohol, in order to realize above-mentioned benefit, it need not apply pressure to reaction mixture.Need provide a kind of in the industry and prepare the method for levulinate from furfuryl alcohol, it is provided for the industrial feasible approach of continuous processing.

Summary of the invention

The present invention is disclosed in the one step process from some embodiments of the method for furfuryl alcohol synthesis of acetyl propionic ester (comprising ethyl levulinate).

This method causes the target levulinate of high yield.This reaction uses final product levulinic acid alkyl ester to carry out in reactor vessel as solvent.This reaction can use non-volatile protic acid for example sulfuric acid carry out.This reaction is also carried out under the pressure around.This reaction can be carried out with substep or continuous mode.Purifying from the levulinate of reaction vessel can also carry out with substep or continuous mode.Purifying need not carry out any special processing to tar residue, to collect product levulinic acid alkyl ester from crude product mixture, because all byproduct residue (comprising tar residue) keep being suspended in the crude product mixture.In most of embodiment, crude product mixture shows as complete homogeneous solution.Byproduct of reaction often keeps flowing and operability, even concentrating also being like this when wherein removing all or nearly all volatile reaction product.Therefore, method of the present invention is provided for the simple and easy synthetic and suitability of continuation method.

Method of the present invention need not used hydrochloric acid; Thereby avoid and specific installation and glass or the relevant unnecessary cost of other non-stainless steel reaction container, and better security is provided and avoids equipment corrosion that produce in the reaction vessel outside because vapor phase is sour.Method of the present invention neither needs also not form for example chlorinated cpds of toxic materials.Method of the present invention does not need a large amount of excessive reagent, thereby elimination needs a large amount of untapped reagent of circulation and further avoids deleterious by product to form.Method of the present invention need not apply pressure to reaction mixture to realize above-mentioned benefit.Method of the present invention is provided for the industrial feasible approach of continuous processing.

Detailed Description Of The Invention

Reaction according to the present invention is used for existing acid catalyst and product levulinic acid alkyl ester to prepare levulinic acid (4-oxopentanoie acid) ester from furfuryl alcohol and alkyl alcohol under as the condition of solvent at the single reaction container.For example, from furfuryl alcohol and ethanol preparation ethyl levulinate, furfuryl alcohol and alcoholic acid mixture are added in the ethyl levulinate in the reaction vessel gradually, in ethanol and the vitriolic mixture.Reaction is proceeded to fully, and final product is obtained through following manner: purifying ethyl levulinate from other reactive components and any unwanted byproduct of reaction (for example insoluble tar).In some embodiments, methyl ester levulinate, levulinic acid n-propyl, the positive butyl ester of levulinic acid isopropyl ester or levulinic acid use methyl alcohol, n-propyl alcohol, Virahol, propyl carbinol and isopropylcarbinol to prepare as alkyl alcohol according to the method for the invention respectively.In some embodiments, use method of the present invention to adopt alkyl alcohol with 1 to 4 carbon.In other embodiments, adopt alkyl alcohol in the method for the invention with a plurality of 4 carbon.

Reaction is by protic acid catalysis.In embodiments, reaction is by strong protic acid catalysis.For the purposes of the present invention, " strong protic acid " is defined as dissociation constant or K under 25 ℃/1 atm pressure _aValue is at least about 55 protonated acid.The example of suitable strong protic acid catalyzer comprises hydrochloric acid, Hydrogen bromide, hydroiodic acid HI, sulfuric acid, pyrosulfuric acid, perchloric acid, Phenylsulfonic acid, methanesulfonic, trifluoromethayl sulfonic acid, p-toluenesulphonic acids, 1-naphthalene sulfonic aicd, 2-naphthene sulfonic acid, chlorsulfonic acid, fluosulfonic acid etc.In embodiments, sulfuric acid is as the protic acid catalyzer.In other embodiments, alkyl-aromatic sulfonic acid, aromatic sulfonic acid or aliphatic sulfonic are as the protic acid catalyzer.In some embodiments, reaction is by weak protic acid catalysis." weak protic acid " is defined as K _aValue is less than 55 protonated acid.The suitable example of useful weak protic acid comprises phosphoric acid, tetra-sodium, polyphosphoric acid, thionamic acid, vitriolic an alkali metal salt (for example sodium pyrosulfate or sal enixum), chloric acid, bromic acid, perbromic acid, acid iodide and periodic acid.Although multiple ordinary method is used hydrochloric acid, sulfuric acid provides advantage:, eliminations non-corrosive relatively for the stainless steel reaction container needs the use glass-clad vessel or the structure of toxic metal material more, reacts to use method of the present invention.

In some embodiments, the protic acid catalyzer is introduced in the solid carrier material, is gone up or covalent bonding.Resin bead, film, porous carbon particle, zeolitic material and other solid carrier materials can be functionalized with the protic acid part, in embodiments, and said protic acid part covalent bonding or be adsorbed to one or more surfaces of solid carrier by force.In non-limitative example, strong cation-exchanging resin (polystyrene resin that for example protonated sulfonate functionalization is crosslinked) is used to adopt method of the present invention to come catalyzed reaction.

In the use of method of the present invention, first mixture is added reactor vessel, and second mixture is added first mixture gradually to promote reaction.First mixture contains the levulinic acid alkyl ester, corresponding to alkyl alcohol, acid catalyst and optional a spot of water of the ester moiety of levulinic acid alkyl ester.Second mixture contains furfuryl alcohol and corresponding to the alkyl alcohol of the additional content of the ester moiety of levulinic acid alkyl ester.

In embodiments, first mixture is through being to mix in about 1: 20 to 1: 1, about 1: 8 to 1: 2 or about 1: 6 to 1: 3 to obtain with the alkyl alcohol and the mol ratio of levulinic acid alkyl ester.Under ethyl levulinate and alcoholic acid situation, this ratio causes the alcoholic acid volume less than 5% to about 30% of first volume of mixture.In embodiments, first mixture also contains the protic acid catalyzer.Sulfuric acid is used as in the embodiment of protic acid catalyzer therein, based on the mole number of the furfuryl alcohol that provides in second mixture, and will about 1x10 ^-4To 2.5x10 ^-2Mole or about in some embodiments 2.5x10 ^-3To 2.5x10 ^-2The mole or in addition other embodiments in about 1x10 ^-2To 2x10 ^-2The sulfuric acid of mole adds first mixture.In some embodiments of method of the present invention, the water of trace is added first mixture.Therein water is added in the embodiment of first mixture, based on the about 1x10 of mole number adding of the furfuryl alcohol that provides in second mixture ^-4To 0.2 mole water, perhaps the mole number based on the furfuryl alcohol that provides in second mixture adds about 1x10 ^-3To 0.1 mole water, perhaps the mole number based on the furfuryl alcohol that provides in second mixture adds about 1x10 ^-3To 5x10 ^-2The water of mole.If even water is not added reaction mixture, in some embodiments, water is forming from polycondensation or other side reactions (for example Aldol condensation) through furfuryl alcohol also.Water adds or is formed in some embodiments in the reaction mixture therein, forms the levulinic acid of trace then through the reaction of chaff alcohol and water.

In embodiments; Second mixture prepares through mixing furfuryl alcohol and alkyl alcohol; Identical in embodiments alkyl alcohol is used for first mixture; The mol ratio of the mole number of furfuryl alcohol and the mole number of alkyl alcohol is about 1: 1.12 to 1: 1.75, and in other embodiments, the mole number of furfuryl alcohol and the mole ratio of alkyl alcohol are about 1: 1.20 to 1: 1.50.In some embodiments, the mole number of the alkyl alcohol in second mixture is selected according to following formula:

D＝(1+(B/A))*C

Wherein A representes the mole number of levulinic acid alkyl ester;

B representes the mole number of alkyl alcohol in said first mixture;

C representes the mole number of furfuryl alcohol; And

D representes the mole number of alkyl alcohol in said second mixture.

In other embodiments, the mole number of the alkyl alcohol in second mixture is chosen as pact (0.9D) to (D), and wherein D as above defines.

In embodiments, when second mixture at first being added (for example not separating out tar residue), the mol ratio of the reagent that calculates as stated causes homogeneous reaction mixture.In embodiments, when second mixture added first mixture gradually, the mol ratio of the reagent that calculates as stated caused stable temperature performance, and stable temperature performance is characterised in that and in the interpolation process, lacks unexpected heat release.In the interpolation process, the mol ratio of the reagent that calculates as stated causes the constant composition (mol ratio of alkyl alcohol and levulinic acid alkyl ester) of reaction mixture to keep basically in the above-mentioned stated limit of B/A.

In above-mentioned those embodiments for example, first mixture heating up to target temperature adds second mixture then.In embodiments, in the process that adds second mixture, keep target temperature.We find that in embodiments the goal response temperature is higher than the temperature of the boiling point of free alkyl alcohol under environmental stress.Alkyl alcohol and levulinic acid alkyl ester form the two-component mixture that boiling point is higher than alkyl alcohol.This so allow the benefit of not expecting of higher editing objective temperature, thereby cause reacting faster speed to form expectation levulinic acid alkyl ester.In embodiments, the target temperature of reaction mixture is to be higher than the boiling point of free alkyl alcohol at least about 20 ℃ or at least about 40 ℃.For example, produce therein in the embodiment of ethyl levulinate, be reflected under about 95-160 ℃ the temperature or under about 110-140 ℃ temperature, carry out with the preparation ethyl levulinate.In some embodiments, first mixture heating up is added second mixture afterwards to the temperature corresponding to the target temperature of reaction mixture.

We find, preferably keep temperature of reaction in the interpolation process or do not causing vigorous reflux in the reaction process subsequently.Realize the optimum yield of levulinic acid alkyl ester, and the formation of insoluble tar material is minimized, when in reaction process, maintaining the temperature at, observe vigorous reflux in this temperature a shade below about 5 ℃.As stated, the advantage of not expecting of method of the present invention is that the boiling point of the mixture of the corresponding levulinic acid alkyl ester with it of alkyl alcohol is higher than the pure boiling point of free alkyl basically.This so around pressure realize down higher basically processing temperature, make this moment have 4 or still less the alkyl alcohol of carbon (for example being lower than the situation of using routine techniques to get) for example add more high boiling solvent to reaction mixture or apply pressure to container.In addition, in embodiments, the levulinic acid alkyl ester that uses in the reaction and the ratio of alkyl alcohol are selected as provides the expected response that does not cause vigorous reflux temperature.Water is added the mixture of alkyl alcohol and levulinic acid alkyl ester, wherein form homogeneous solution, this also influences the boiling point of mixture.For example, ethanol and the boiling point that causes following mixing the (randomly comprising water) of ethyl levulinate recording (referring to the process of the test of embodiment 1, to be used to measure these boiling point values):

Significantly, in order to obtain optimum total recovery and speed of response, the ratio of alkyl alcohol and levulinic acid alkyl ester also should be united the ratio and the calculation result of mentioned reagent and selected.

Second mixture adds in the reception solution of pre-warmed vigorous stirring within a certain period of time gradually.In some embodiments, second mixture adds with the form of the shunting of second mixture gradually.In some such embodiments, shunting is to drip.In other embodiments, shunting is fine smog or drop spraying, and wherein the average droplet size of drop is that 1mm is to micron grain size.In embodiments, the size of drop is selected to provide to the maximum speed of adding of the mixed effect equilibrated of first and second mixtures.In some embodiments, based on the mole number of the alkyl alcohol in first mixture, the adding proportion of second mixture and first mixture be about 1 to 5 mole of % furfuryl alcohol/minute.In embodiments, the quick formation of the homogeneous solution of first and second mixtures makes owing to tar residue forms the yield reduction that causes and minimizes.For example, in some embodiments, a plurality of spray orifices are housed reaction vessel or nozzle drips or spraying rather than the interpolation of stream shape to provide to add second mixture.In other example, in some embodiments, second mixture adds first mixture through one or more holes or the nozzle that does not contact first mixture.In such embodiment, any tar residue that in reaction mixture, forms does not disturb reagent to add in the reaction vessel, promptly at the location point that second mixture is added first mixture.

In embodiments, reaction mixture reaches ambient pressure.In embodiments, pressure uses method of the present invention to realize the levulinic acid alkyl ester of high yield amazedly around.Use ambient pressure and the ability that realizes high yield be method of the present invention be used for laboratory and technical scale process and in batches with the favourable characteristic of successive reaction scheme.Yet reaction is not limited to the ambient pressure condition.In some embodiments, bring pressure to bear on reaction vessel with the attainable temperature of reaction that for example raises, thus and raising speed of response.For example, in some embodiments, apply about 1atm (1.03kg/cm on barometric point to the barometric point ²) pressure.In other embodiments, apply about 1atm (1.03kg/cm on the barometric point ²) to 10atm (10.33kg/cm ²) pressure.In addition other embodiments in, apply about 10atm (10.33kg/cm on the barometric point ²) to 50atm (51.66kg/cm ²) pressure.Reaction conditions is not limited to be applied to the amount of the pressure of reaction vessel; Therefore; In various embodiments; The pressure of uniting method use of the present invention is selected can optimize reaction parameter, for example the ability that minimizes or arrive the destination agent ratio of the output of the interpolation speed of reagent, speed of response, attainable temperature, reagent or product, one or more side reactions (for example tar formation).

According to the last stage reaction of one or more methods of the present invention and before its reaction product of purifying, based on the mole number of the furfuryl alcohol that provides in second mixture, crude product mixture contains the levulinic acid alkyl ester at least about 70 moles of % yields.In some embodiments, based on the mole number of the furfuryl alcohol that provides in second mixture, crude product mixture contains the levulinic acid alkyl ester at least about 80 moles of %.In some embodiments, based on the mole number of the furfuryl alcohol that provides in second mixture, crude product mixture contains the levulinic acid alkyl ester of about at the most 85 moles of % yields.In some embodiments, based on the mole number of the furfuryl alcohol that provides in second mixture, crude product mixture contains the levulinic acid alkyl ester of about at the most 90 moles of % yields.In some embodiments, based on the mole number of the furfuryl alcohol that provides in second mixture, crude product mixture contains total levulinate (being that the levulinic acid alkyl ester adds levulinic acid) of about at the most 70 moles of % yields.In some embodiments, based on the mole number of the furfuryl alcohol that provides in second mixture, crude product mixture contains total levulinate (being that the levulinic acid alkyl ester adds levulinic acid) of about at the most 80 moles of % yields.In some embodiments, based on the mole number of the furfuryl alcohol that provides in second mixture, crude product mixture contains total levulinate (being that the levulinic acid alkyl ester adds levulinic acid) of about at the most 85 moles of % yields.In some embodiments, based on the mole number of the furfuryl alcohol that provides in second mixture, crude product mixture contains total levulinate (being that the levulinic acid alkyl ester adds levulinic acid) of about at the most 90 moles of % yields.In some embodiments, based on the mole number of the furfuryl alcohol that provides in second mixture, crude product mixture contains total levulinate (being that the levulinic acid alkyl ester adds levulinic acid) of about at the most 95 moles of % yields.

In some embodiments, the soluble material in the crude product mixture does not contain furfuryl alcohol, only contains alkyl alcohol, levulinic acid and levulinic acid alkyl ester, and for example proton N MR, HPLC or GC measure through analytical procedure for these.In some embodiments, crude product mixture comprises angelica lactone.In some such embodiments, about 1% angelica lactone records through GC-MS.In embodiments, the detectable by product of reaction is a tar residue, and it is about 20 weight % or the lower furfuryl alcohol that adds in embodiments.In some embodiments, tar residue is 10 weight % or the lower furfuryl alcohol that adds.In some embodiments, tar residue is 5 weight % or the lower furfuryl alcohol that adds.The content of tar residue is measured through following manner: evaporation alkyl alcohol and levulinic acid alkyl ester, and residuals or its equal portions in the reaction vessel of weighing.

In some embodiments, reaction is carried out fully with batch process.In other embodiments, reaction is carried out with continuous processing.In some embodiments, continuous processing is preferably carried out in industrial setting.In some such embodiments; The reaction mixture of one or more equal portions is regularly removed in reaction process, or the reduction continuously in the process of second mixture adding reaction vessel, in the interpolation of second mixture or during both of the percentage by volume of reaction mixture.In the embodiment that some reaction mixtures are removed from reaction vessel therein, the levulinic acid alkyl ester of additional content, alkyl alcohol and catalyzer can add reaction vessel to promote the successive processes of reaction.In such embodiment, the preferred speed of removing and the interpolation speed of regulating is with the temperature performance that constant is provided and the ratio of reagent and reaction product.For example, react therein in some embodiments of carrying out with continuous processing.Infeed continuously in the process of first mixture at second mixture additional protic acid catalyzer is added reaction vessel; With remedy the protic acid catalyst concn in reaction mixture owing to second mixture adds the dilution that causes in first mixture gradually, wherein first mixture contains the protic acid catalyzer of initial equal portions.Preferably, in such embodiment, additional protic acid catalyzer uses the nozzle of independent hole or orifice nozzle or use to introduce so that second mixture is added reaction vessel.

In embodiments, method of the present invention causes a spot of amazedly tar residue to form.The formation of tar residue and separate out or solidify be from furfuryl alcohol prepare levulinic acid and levulinate before the shortcoming of currently known methods.Separating out or solidifying obstruction of tar residue uses these synthetic with continuous processing, because reactor drum and purification system are contaminated apace, thereby reduce effective yield of expectation levulinate and improves its production cost.Than ordinary method, use the reaction of method of the present invention to be characterised in that to be taken aback and lack tar residue separating out or solidify in reaction vessel basically.Therefore, method of the present invention provide with respect to before the remarkable advantage of currently known methods.In embodiments, use the operation of method of the present invention to cause tar residue less than 10 weight % of furfuryl alcohol.In other embodiments, use the operation of method of the present invention to cause about 5 weight % or lower tar residue less than furfuryl alcohol.In some embodiments, the tar residue that forms like this keeps complete suspendible in reaction process, and in reaction mixture or crude product mixture, does not separate out or solidify.Tar residue keeps suspendible or is dispersed in the embodiment in the crude product mixture therein, and method of the present invention is very suitable for continuous processing, and wherein tar residue separates out or solidify otherwise will pollute reactor apparatus.

Do not hope to receive the restriction of theoretical statement, we believe and exist the levulinic acid alkyl ester to help to prevent that through the solubleness that keeps reagent tar residue from forming as solvent; We believe that also the temperature of ratio of reagents association response mixture provides the higher speed of response of levulinic acid alkyl ester, and tar formation more long response time is responsible in this and then obstruction.

In some embodiments, when second mixture added first mixture fully, furfuryl alcohol was complete basically to the conversion of levulinic acid alkyl ester.Advantageously add heating of the first mixture continued and stirring fully in other embodiments at second mixture.In batch type process, in embodiments, after second mixture adds first mixture fully, be transformed into the levulinic acid alkyl ester at about 1 to 120 minute, or about 60 minutes, or accomplish in about 30 minutes.

The levulinate final product can reclaim from reaction mixture through means known in the art (comprising distillation).Normally used any other routine techniques of preferably vacuum distilling of the distillation of levulinic acid alkyl ester, falling-film distillation, commentaries on classics membrane distillation or those skilled in the art.In some embodiments, before the distillation of said levulinic acid alkyl ester, excessive alkyl alcohol can be removed from reaction mixture and recycle through currently known methods.Before levulinic acid alkyl ester purifying, can expect the protic acid that exists in the neutralization reaction mixture.Neutralization is accomplished through following manner: a certain amount of neutralizing agent is added in the reaction mixture, during this amount is enough to the protic acid catalyzer.Alkalescence and alkaline earth metal hydroxides, carbonate, supercarbonate, phosphoric acid salt, tertiary amine or institute's hydrochlorate are the examples of the suitable neutralizing agent of the protic acid catalyzer that exists in the neutralization reaction mixture.For example Sodium phosphate, dibasic and quicklime are useful to buffer reagent in some embodiments.MOX neutralizing agent (for example alkali alumina) also is provided at insoluble characteristic in the reaction mixture, and therefore after neutralization, for example separates from reaction mixture easily through filtration, decant or deposition.

Because the processing advantage that the method for the application of the invention realizes, the flow reactor design that is used for the method for embodiment of the present invention is not particularly limited scope.In some embodiments, main processing advantage comprise at a high speed conversions, high yield, do not have solvent recovery step, lower or need not exert pressure, low-level tar residue forms, lack that tar residue is separated out and when the volatility final reacting product partially or completely evaporates the tar residue maintenance can flow.In embodiments, these processing advantages cause uniting the reactor drum of method use of the present invention and the substantial flexibility of purification devices design.In some embodiments, the merging of uniting of apparatus characteristic provides the optimal speed of reaction and the yield of levulinic acid alkyl ester with the water-content (if having) based on temperature, pressure, material composition, mixing, interpolation speed, acid content and expectation.Some non-limitative examples of possible assembly and combination thereof comprise following:

1. the high-speed stirring nozzle adds continuously stirring jar reactor drum, or CSTR, or many CSTR tandem reactor.

2. CSTR reactor drum behind the plug flow reactor or tandem reactor.

3. circulate ring-like reactor drum or tandem reactor have static mixer or online machine mixing tank in large-scale equipment more the dilution and the mixing of improvement to be provided.

4. circulate ring-like reactor drum or tandem reactor have the trunk for expansion between the inner or ring of ring, to allow incompressible gas to remove or to increase residence time.

5. the ring-like reactor drum of circulation in above-mentioned any embodiment is plug flow reactor then.

6. reaction distillation has circulation products stream and heterogeneous catalyst will separate and dilution merges in the step.

7. reaction distillation has circulation products stream and homogeneous catalyst will separate and dilution merges in the step.

8. placed in-line loop or CSTR in above-mentioned any embodiment have to the fresh material of the continuum source in each stage.

In some embodiments, use finishing reactor to come the levulinic acid alkyl ester of any residual levulinic acid to the expectation in the esterification crude product mixture.In some embodiments of method of the present invention, form levulinic acid, wherein water add reaction mixture or wherein water form as by product, as stated.After in finishing reactor, carrying out esterification, reaction mixture is the reaction mixture of esterification.Being used in batches or continuously, the unrestricted example of the possible finishing reactor of method comprises following:

1.CSTR, wherein add excessive alkyl alcohol, and water and alkyl alcohol are removed to carry out esterification.

2. lack the pallet distillation.

3. reaction distillation, wherein alkyl alcohol boils from reactor bottom, and in the presence of fixed bed catalyst the contact levulinic acid.

In some embodiments, the neutralization of acid catalyst is carried out through using above-mentioned neutralizing agent in the reaction mixture of crude product mixture or esterification.In embodiments, the reaction mixture of reaction mixture or esterification by esterification to form the neutral reaction mixture.In some embodiments available in batches or continuously method neutralize, comprise following:

1. heterogeneous neutralization bed, it has solid neutralizing agent (for example Sodium phosphate, dibasic or quicklime), is strainer then, and reaction mixture passed through this strainer before leaving bed.

2. will in reaction mixture, add the backflow mixing tank by soluble one or more solid neutralizing agents, filter then to remove solid.

3. one or more liquid tertiary amines are added the backflow mixing tank, filter then to remove solid.

4. one or more water-soluble neutralising agents (for example sodium hydroxide) are added the backflow mixing tank, filter then or concentrate to remove solid.

In embodiments, crude product mixture, the reaction mixture of esterification or neutral reaction mixture contain excessive alkyl alcohol, tar residue and product levulinic acid alkyl ester.In some embodiments, expectation is through from crude product mixture, and the reaction mixture of esterification or neutral reaction mixture are removed excessive alkyl alcohol, tar residue or both and purified product levulinic acid alkyl ester.In some embodiments, through to crude product mixture, the reaction mixture of esterification or neutral reaction mixture carry out vacuum distilling and realize purifying.In embodiments, useful vacuum distillation plant comprises system, comprises post, reboiler, condensing surface and return flow path.In some embodiments, the twin columns design is applicable to distills, and wherein first post moves under elevated pressures with steaming and falls some percentile residual alkyl alcohols, and second post moves to remove residual alkyl alcohol under lower pressure.In some embodiments, slurry type design or mechanical type reboiler for example Rota-film evaporator (WFE) be used for the separating acetylpropionic acid alkyl ester product.

In some embodiments, crude product mixture, the purifying of the reaction mixture of esterification or neutral reaction mixture is realized in more than a step, is two steps more than a step in embodiments.In some such embodiments, the first step comprises the most alkyl alcohol of evaporation, thereby causes removing the reaction mixture that mainly contains levulinic acid alkyl ester and tar residue.In some such embodiments, tar residue keeps being suspended in the reaction mixture of removing.Second step comprised a part of levulinic acid alkyl ester of evaporation from the reaction mixture of removing, to produce a large amount of for example levulinic acid alkyl esters of 50 weight % (it is produced as purified product in reaction).In some embodiments of reaction, wherein easy vacuum distilling is used for from the reaction mixture separating acetylpropionic acid alkyl ester product of removing, and the levulinic acid alkyl ester separation of 50 weight % to 75 weight % is a purified product; In other embodiments, the levulinic acid alkyl ester separation of 75 weight % to 90 weight % is a purified product; In other embodiments, the levulinic acid alkyl ester separation of 90 weight % to 99 weight % is a purified product.The characteristic of not expecting of the present invention is in some embodiments; Residual tar residue is can flow with machinable in the reaction mixture of removing; Even more than the levulinic acid alkyl ester separation of the formation of 50 weight %, and the weightening finish cut of residual reaction mixture is made up of tar residue.If it is flowable that tar residue keeps, use the mechanical assistance evaporation technique, for example change film evaporation or falling film evaporation.In some embodiments, for the separating acetylpropionic acid alkyl ester, because they are more effective than easy evaporation technique.

In some such embodiments, being separated in two steps of levulinic acid alkyl ester realizes.The levulinic acid alkyl ester of the first step separating most from the reaction mixture of removing is with residual flowable tar residue in the high solid reaction mixture.Second step was used distillation plant then, and it is reboiler or the vaporizer of design with management high solid reaction mixture.In some embodiments; WFE; Falling film evaporation; Spraying drying; High solid management type reboiler (for example

or

equipment; By Butzbach; The Buss-SMS-Canzler GmbH of Germany sells); Spray-dryer, or other solid drying equipment are as after-fractionating equipment.Second reboiler/evaporator unit can also directly be sent to first distillation plant that uses in the first step with steam; Promptly two reboilers can provide same column, make that materials evaporated sends back to first reboiler in second reboiler.

Yet; In some embodiments of method of the present invention; Also attempt from the crude mixture of removing, separating the levulinic acid alkyl ester that surpasses about 50 weight % through above-mentioned evaporation technique; Because increase the weight cut of tar residue, this is in-problem, it forms high viscosity or even curing material (it is inappropriate for above-mentioned purification process).In some such embodiments; Expectation forms the plasticizing tar residue: promptly; One or more compounds are added in the tar residue, and this prevents to solidify and/or guarantees that residue keeps mobile can separate the levulinic acid alkyl ester of substantial part through above-mentioned evaporation technique effectively.In some such embodiments; We find, biodiesel fuel are added crude product mixture, the reaction mixture of esterification; Neutral reaction mixture or the reaction mixture of removing form the flowable tar residue of plastifying, and it can not solidify in evaporative process.Because tar residue itself is used for burning (promptly having fuel value), the interpolation of biofuel has replenished the practicality of plastifying tar residue, and this remains unchanged or even increases after all levulinic acid alkyl ester separation basically.In some embodiments, under reaction conditions basically inertia and the boiling point solvent that is higher than the tar residue of levulinic acid alkyl ester be used for plastifying tar residue in the evaporative process of levulinic acid alkyl ester; Solvent evaporation is used for fuel value with residual solidified tar residue or incendivity in some such embodiments then.In some embodiments, the tetrahydrofurfuryl alcohol (THFA) of trace adds second mixture (mixture contains the furfuryl alcohol original material), reacts afterwards.In embodiments; THFA can react to form levulinic acid tetrahydrofurfuryl alcohol ester with furfuryl alcohol; It is the good softening agent of tar residue in some embodiments, and it has low vp, and burns together with tar residue in some embodiments and be used for fuel value.

In other such embodiments, liquid/liquid separates and is used for the some or all of levulinic acid alkyl esters that from the tar residue separating reaction, form.The non-limitative example of available solvent comprises linearity from tar residue extraction levulinic acid alkyl ester, branching, or annular aliphatic or aromatic hydrocarbon (for example hexane, toluene etc.); Sherwood oil, ETHYLE ACETATE and biofuel.

In embodiments, the present invention is a kind of method of synthesis of acetyl alkyl propionates, and this method comprises:

A. make first mixture contact second mixture to form reaction mixture, said first mixture comprises:

I. alkyl alcohol,

Ii protic acid catalyzer and

Iii. levulinic acid alkyl ester, the alkyl of wherein said alkyl and said alkyl alcohol is identical;

Said second mixture comprises:

I. furfuryl alcohol and

Iii. the said alkyl alcohol of said first mixture of additional content; And

B. in said reaction mixture, form the levulinic acid alkyl ester, the alkyl of wherein said alkyl and said alkyl alcohol is identical.

In embodiments, the levulinic acid alkyl ester at high temperature forms.In embodiments, said second mixture contacts said first mixture, and said first mixture keeps at high temperature.In embodiments, said alkyl alcohol is a methyl alcohol, ethanol, n-propyl alcohol, Virahol or propyl carbinol.In embodiments, the mol ratio of alkyl alcohol and levulinic acid alkyl ester is about 1: 20 to 1: 1 in said first mixture.In embodiments, the mol ratio of alkyl alcohol and levulinic acid alkyl ester is about 1: 8 to 1: 2 in said first mixture.In embodiments, the mol ratio of alkyl alcohol and levulinic acid alkyl ester is about 1: 6 to 1: 3 in said first mixture.In embodiments, said protic acid catalyzer is a sulfuric acid, comprises sulfonic Zeo-karb, alkyl-aromatic sulfonic acid, aromatic sulfonic acid or aliphatic sulfonic.In embodiments, the furfuryl alcohol that provides in every mole said second mixture will about 1x10 ^-4To 2.5x10 ^-2The sulfuric acid of mole adds said first mixture.In embodiments, the furfuryl alcohol that provides in every mole said second mixture will about 2.5x10 ^-3To 2.5x10 ^-2The sulfuric acid of mole adds said first mixture.In embodiments, the furfuryl alcohol that provides in every mole said second mixture will about 1x10 ^-2To 2x10 ^-2The sulfuric acid of mole adds said first mixture.In embodiments, the present invention also comprises water is added said first mixture.In some such embodiments, the furfuryl alcohol that provides in every mole said second mixture adds about 1x10 ^-4Water to 0.2 mole.In some such embodiments, the furfuryl alcohol that provides in every mole said second mixture adds about 1x10 ^-3Water to 0.1 mole.In some such embodiments, the furfuryl alcohol that provides in every mole said second mixture adds about 1x10 ^-3To 5x10 ^-2The water of mole.In embodiments, to comprise the mol ratio of the mole number of furfuryl alcohol and alkyl alcohol be about 1 to 2 to said second mixture.In embodiments, to comprise the mol ratio of the mole number of furfuryl alcohol and alkyl alcohol be about 1: 1.125 to 1: 1.75 to said second mixture.In embodiments, to comprise the mol ratio of the mole number of furfuryl alcohol and alkyl alcohol be about 1: 1.20 to 1: 1.50 to said second mixture.In embodiments, reaction comprises heating and stirs.In some such embodiments, said alkyl alcohol is that ethanol and said high temperature are about 95 ℃ to 160 ℃.In embodiments, this method heats said first mixture before also being included in said contact.In some such embodiments, said heating comprises that elevated temperature is on the boiling point of said alkyl alcohol.In some such embodiments, said temperature than the boiling point height of said alkyl alcohol at least about 20 ℃.In some such embodiments, said temperature than the boiling point height of said alkyl alcohol at least about 40 ℃.. in some such embodiments, said method is a batch process, and said second mixture contacts and after said first mixture is accomplished said heating kept about 1 to 60 minute.In some such embodiments, said method is a batch process, and said second mixture contacts and after said first mixture is accomplished said heating kept about 30 minutes.In some embodiments, the mole number of alkyl alcohol is selected according to following formula in said second mixture

D＝(1+(B/A))*C

Wherein

A representes the mole number of levulinic acid alkyl ester;

B representes the mole number of alkyl alcohol in said first mixture;

C representes the mole number of furfuryl alcohol; And

D representes the mole number of alkyl alcohol in said second mixture.

In some such embodiments, the mole number of alkyl alcohol is selected as pact (0.9) (D) to D in said second mixture.In embodiments, with the ratio of about 1 to the 5 mole of % of alkyl alcohol in said first mixture of every mole of PM, furfuryl alcohol contacts the alkyl alcohol in the said reaction mixture.In embodiments, said contact comprises through one or more nozzle or spray orifices that do not contact said first mixture said second mixture is added said first mixture.

In some such embodiments, said one or more nozzles or spray orifice are constructed to make streamed said second mixture of branch of the smog that comprises drop or fine spraying to contact the surface of said first mixture.In embodiments, said method is a successive.In embodiments, reaction comprises and exerting pressure.In embodiments, said exerting pressure is about 1 normal atmosphere of projecting pressure at the most.In embodiments, the yield of said levulinic acid alkyl ester be the furfuryl alcohol in said second mixture mole number at least about 70 moles of %.In embodiments, this method also is included in and forms the said acid catalyst of levulinic acid alkyl ester post neutralization.In some such embodiments, said neutralization realizes through oxyhydroxide, carbonate, supercarbonate, phosphoric acid salt, tertiary amine or the carboxylate salt of alkali or earth alkali metal.In embodiments, this method comprises the levulinic acid alkyl ester of collecting formation.In some such embodiments, said collection comprises the evaporation of alkyl alcohol, the distillation of said levulinic acid alkyl ester; Soluble reaction products is decant in the soluble reaction products never; Soluble reaction product is filtered from soluble reaction products, and liquid liquid separates, or its combination.In some such embodiments, said distillation comprises and applies vacuum.In some such embodiments, said distillation comprises changes film evaporation or falling film evaporation.In some such embodiments, said being collected in two steps realizes that wherein the first step comprises the evaporation of alkyl alcohol; And second the step comprise the evaporation of levulinic acid alkyl ester; Perhaps the first step comprises the evaporation of the levulinic acid alkyl ester of alkyl alcohol and first part, and second step comprised the levulinic acid alkyl ester of removing second section.In some such embodiments, this method also is included in the said the first step and between said second step tar residue softening agent is added said reaction mixture.In some such embodiments, said tar residue softening agent is a biodiesel fuel, 2; 2,4-trimethylammonium-1,3-pentane-glycol diisobutyrate; Tridecyl alcohol, wherein alkyl has the bialkyl ortho phthalate of 4 to 14 carbon independently, and wherein alkyl has the hexanodioic acid dialkyl of 4 to 14 carbon independently; Wherein alkyl has the DAS di alkyl sebacate of 4 to 14 carbon independently; Wherein alkyl has the mono benzoate of 4 to 14 carbon, and wherein alkyl has the dialkyl cyclic capronate of 4 to 14 carbon independently, and wherein alkyl has the tri trimellitate alkyl ester of 4 to 14 carbon independently; Wherein alkyl has the citric trialkyl ester of 4 to 14 carbon independently, or its combination.In embodiments, levulinic acid is the by product of this method, and wherein this method also comprises the esterification levulinic acid.In some such embodiments, after formation the merging yield of levulinic acid alkyl ester and levulinic acid be the furfuryl alcohol that provides in said second mixture mole number at least about 70 moles of %.. in embodiments, be collected as purified product greater than the levulinic acid alkyl ester of the formation of 75 weight %.In embodiments, the levulinic acid alkyl ester greater than the formation of 90 weight % is collected as purified product.

In embodiments, method of the present invention is a kind of method of synthesis of acetyl alkyl propionates, comprising:

A. form first mixture, said first mixture comprises:

I. alkyl alcohol,

Ii protic acid catalyzer and

B. heat the temperature of said first mixture to the boiling point that is higher than said alkyl alcohol at least about 20 ℃;

C. make said first mixture contact second mixture to form reaction mixture under the pressure around, said second mixture comprises:

I. furfuryl alcohol and

Iii. be the alkyl alcohol from the alkyl alcohol of said first mixture, wherein the mol ratio of furfuryl alcohol and alkyl alcohol is about 1: 1.125 to 1: 1.75;

Said reaction mixture is reacted to form the levulinic acid alkyl ester under pressure and about 95 ℃ to the 160 ℃ temperature around, and the alkyl of wherein said alkyl and said alkyl alcohol is identical; And

E. reclaim said levulinic acid alkyl ester,

Wherein based on the mole number of furfuryl alcohol in said second mixture, the sulfuric acid of about 0.01 to 2 mole of % is added said first mixture, and the mole number of alkyl alcohol is selected as about 0.9D to D in wherein said second mixture, wherein D defines according to following formula

D＝(1+(B/A))*C

Wherein

A representes the mole number of levulinic acid alkyl ester;

B representes the mole number of alkyl alcohol in said first mixture;

C representes the mole number of furfuryl alcohol; And

D representes the mole number of alkyl alcohol in said second mixture.

In embodiments, said alkyl alcohol is a methyl alcohol, ethanol, Virahol, n-propyl alcohol or propyl carbinol.In some such embodiments, said alkyl alcohol is an ethanol.In some embodiments, this method also is included in said collection neutralisation of sulphuric acid before.

Test

The following example is described the present invention.

Embodiment 1

Magnetic stirring bar is housed; Thermopair; The 250mL 3 neck flasks of condensing surface and diaphragm of rubber add the 100mL ethyl levulinate (derive from the Langfang Triple Well Chemicals Company of Chinese Hebei province Langfang City, Ltd.) with 5mL ethanol (100%, derive from Sigma-Aldrich; St.Louis, MO).Using heating mantles that flask is added pines for refluxing.Boiling point was stabilized in 154.2 ℃ in 25 minutes.With 10 minutes at interval, use syringe to add flask through diaphragm of rubber the ethanol of three parts of continuous 5mL equal portions, the record boiling point.At last, the deionized water with 1mL adds flask through rubber.Boiling point is record after 10 minutes.Table 1 illustrates the boiling point of the record of mixture.

The table 1. ethanol/membranous boiling point of ethyl levulinate mixture.

Embodiment 2

500mL 3 neck flasks are equipped with magnetic stirring bar, tap funnel, condensing surface and thermopair.Flask adds 100.06g (0.694mol) ethyl levulinate and (derives from the Langfang Triple Well Chemicals Company of Chinese Hebei province Langfang City; Ltd.) 11.48g (0.249mol) ethanol (99.5+%; Derive from Acros Organics of Geel, Belgium) and sulphuric acid soln (preparing) through in the 1.463mL deionized water, mixing the 0.575mL vitriol oil.Mixture is stirred and in 120 ℃ of oil baths, is heated to 107.0 ℃ of backflows.49.23g (0.497mol) furfuryl alcohol (99%, derive from Acros Organics) and 31.50g (0.684mol) alcoholic acid mixture were dropped to reaction mixture in 108 minutes.After accomplishing interpolation, the other 1h of reaction backflow.Reaction flask is taken out from oil bath, and allow to be cooled to surrounding temperature.

Removing the crude product mixture sample is used for analyzing.Crude reaction product is dissolved in MTBE, and this causes a small amount of tar residue to be separated out, and it also stands GC-MS.Main peaks is confirmed as 98.9% ethyl levulinate; Small peak is confirmed as angelica lactone.Because detecting ethanol, its volatility GC-MS do not exist.

When stirring, sodium hydroxide solution (preparing through in 1mL zero(ppm) water and 9mL ethanol, mixing 0.884g sodium hydroxide) is added reaction mixture.Mixture is through distilling to obtain the distillatory reaction product in 2-3 holder vacuum distilling.The undistilled residue and residual of about 8.49g is stayed the distillment bottom.Undistilled solid contains the sodium sulfate of the 1.53g that has an appointment and the tar residue of about 6.96g.The amount of tar residue is for adding 14.1 weight % of the furfuryl alcohol weight of reacting.The percentage that the GC-MS vestige of distillatory reaction product causes recording main peaks is 99% to be ethyl levulinate.

Embodiment 3

Magnetic stirring bar is housed; Tap funnel; 500mL 3 neck flasks adding 100.21g (0.695mol) ethyl levulinate of condensing surface and thermopair (derive from the Langfang Triple Well Chemicals Company of Chinese Hebei province Langfang City, Ltd.), 7.60g (0.165mol) ethanol (99.5+%; Derive from Acros Organics of Geel, Belgium) and sulphuric acid soln (preparing) through in the 1.463mL deionized water, mixing the 0.575mL vitriol oil.Mixture is stirred and in 135 ℃ of oil baths, is heated to 116.3 ℃ of backflows.49.12g (0.496mol) furfuryl alcohol (99%, derive from Acros Organics) and 28.72g (0.624mol) alcoholic acid mixture were dropped to reaction mixture in 115 minutes.After accomplishing interpolation, the other 1h of reaction backflow.Then reaction flask is taken out from oil bath, and allow to be cooled to room temperature.

The reaction mixture of about 50.445g is transferred to the 250mL flask, and uses Kugelrohr equipment in about 7-10 holder with distill under 180 ℃ the airbath temperature at the most.After distillation, the undistilled tar solid total amount of staying in the flask is 1.622g, and it contains sulfuric acid 0.290g and tar 1.332g.The ratio of the amount of the amount of the tar that forms in the reaction and the furfuryl alcohol of adding is 9.8 weight %.The GC-MS that as embodiment 1, carries out crude reaction product analyzes, and shows that ethyl levulinate is presented as 98.6%.

Comparative example 4

Magnetic stirring bar is housed; Tap funnel; The 500mL 3 neck flasks of condensing surface and thermopair add 62.24g (1.351mol) ethanol, and (200 degree derive from Acros Organics of Geel, Belgium) with sulphuric acid soln (preparing through the mixing 0.575mL vitriol oil in the 1.463mL deionized water).With mixture in 100 ℃ of oil baths 76 ℃ of backflows.The furfuryl alcohol (99%, derive from Acros Organics) of about 49mL is added tap funnel.About 2mL furfuryl alcohol of initial equal portions drops to reaction mixture from tap funnel.In the interpolation process, the solid tar of observing obvious amount is accumulated in the flask.Because therefore the accumulation of solid tar can not add the residue furfuryl alcohol from tap funnel.Reaction flask is taken out and allows to be cooled to room temperature from oil bath.

Embodiment 5

Use the positive butyl ester of levulinic acid (to derive from the Langfang Triple Well Chemicals Company of Chinese Hebei province Langfang City; Ltd.) and propyl carbinol (99.9%; Derive from Sigma-Aldrich Company of St.Louis, MO) repeat the method for embodiment 1.Table 2 illustrates the boiling point of the record of mixture.

The boiling point of the positive butyl ester mixture of table 2. propyl carbinol/levulinic acid

Magnetic stirring bar is housed; Tap funnel, the 500mL 3 neck flasks of condensing surface and thermopair add the positive butyl ester of 100.04g (0.581mol) levulinic acid and (derive from the Langfang Triple Well Chemicals Company of Chinese Hebei province Langfang City, Ltd.); 20.84g (0.281mol) propyl carbinol (99.9%; Derive from the Sigma-Aldrich Company of St.Louis, MO), the 1.463mL deionized water and the 0.575mL vitriol oil.Use the temperature of heating mantles with mixture heating up to 130 ℃.With 49.07g (0.495mol) furfuryl alcohol (99%, derive from Acros Organics of Geel, Belgium) and the mixture of 55.00g (0.742mol) propyl carbinol in about 65 minutes, be added dropwise to reaction mixture.After accomplishing interpolation, temperature of reaction was kept other 1 hour at 130 ℃.Then, allow reaction flask to be cooled to room temperature.Crude product mixture shows as homogeneous, does not observe material soluble or that be separated.The reaction mixture of about 50.10g is transferred to the 250mL flask, and uses Kugelrohr equipment in about 7-10 holder with distill under 181 ℃ the airbath temperature at the most.

After distillation, the undistilled solid total amount of staying in the flask is 1.43g, and it contains the tar residue of 0.23g sulfuric acid and 1.20g.The amount of the tar residue that adds is measured as 11.1 weight % with the ratio of the amount of furfuryl alcohol.The GC-MS that as embodiment 2, carries out crude reaction product analyzes, and shows that the positive butyl ester of levulinic acid is presented as 98.0% of peak area.

Comparative example 6

Magnetic stirring bar is housed; Tap funnel; The 500mL 4 neck flasks of condensing surface and thermopair add 100.16g (1.351mol) propyl carbinol (from deriving from Acros Organics of Geel, the 99.4% propyl carbinol vapor enrichment of Belgium) and sulphuric acid soln (preparing through in 1.463mL zero(ppm) water, mixing the 0.575mL vitriol oil).With mixture in 120 ℃ of oil baths 95 ℃ of backflows.49.38g (0.498mol) furfuryl alcohol (99%, derive from Acros Organics) was added tap funnel in 110 minutes.In the interpolation process, observe solid tar material accumulating in flask.After accomplishing interpolation, make the other 1h of reaction backflow.Then reaction flask is taken out from oil bath, and allow to be cooled to room temperature.The gross weight of crude product mixture is 149.22g.Reaction back total mass loss is 2.84g.

Embodiment 7

Magnetic stirring bar is housed; The 2L 2 neck flasks of Dean-Stark scoop and thermopair add 232.52g (2.002mol) levulinic acid and (derive from the Langfang Triple Well Chemicals Company of Chinese Hebei province Langfang City; Ltd.), and 241.52g (4.019mol) n-propyl alcohol (>=99.8%, derive from Sigma-Aldrich Company of St.Louis; MO), the 600mL toluene and the 2mL vitriol oil.Be reflected at and be heated to backflow on the heating mantles.After backflow is spent the night, collect the water of total amount 42.7mL, and remove from the Dean-Strap scoop.Reaction flask allows to be cooled to room temperature.The 100g alkali alumina (derives from Sigma-Aldrich Company of St.Louis, MO) added reaction soln and stir about 80 minutes then.Filter out solid then, will filtrate on rotatory evaporator concentrates, and filtrating being immersed in the flask is set in 75 ℃ the oil bath and 15 holder vacuum tightnesss, to remove toluene and n-propyl alcohol.Residue distills in the flask that is being immersed in the oil bath that is set at 110 °-120 ℃ and 15 holder vacuum tightnesss on the rotatory evaporator, in catching flask, to produce the 284.48g colourless liquid.Product is confirmed as 99.51% levulinic acid n-propyl through GC-MS.

Use n-propyl alcohol and levulinic acid n-propyl, the method for embodiment 1 is used to produce the boiling point performance.The boiling point of measuring is shown in table 3.

The boiling point of table 3. n-propyl alcohol/levulinic acid n-propyl mixture

500mL 4 neck flasks are equipped with magnetic stirring bar, tap funnel, condensing surface and thermopair.Flask adds 100.02g (0.632mol) levulinic acid n-propyl (synthetic from above-mentioned levulinic acid), 16.48g (0.274mol) n-propyl alcohol, 1.463mL deionized water and the 0.575mL vitriol oil.Mixture is heated to 120 ℃ temperature with heating mantles.49.07g (0.495mol) furfuryl alcohol (99%, derive from Acros Organics of Geel, Belgium) and the mixture of 43.06g (0.716mol) n-propyl alcohol in about 117 minutes, drop to reaction mixture.After accomplishing interpolation, reaction refluxed other 1 hour.Reaction flask allows to be cooled to room temperature then.Crude product mixture shows as homogeneous, does not observe material soluble or that be separated.The reaction mixture of about 50.10g is transferred to the 250mL flask, and uses Kugelrohr equipment in about 4-8 holder with distill under 179 ℃ the airbath temperature at the most.

After distillation, the undistilled solid total amount of staying in the flask is 1.16g, and it contains the tar residue of 0.25g sulfuric acid and 0.91g.The ratio of the amount of the amount of the tar residue that forms in the reaction and the furfuryl alcohol of adding is 7.8%.The GC-MS that as embodiment 2, carries out crude reaction product analyzes, and shows that the levulinic acid n-propyl is presented as 99.1%.

Embodiment 8

Magnetic stirring bar is housed; The 2L 3 neck flasks of Dean-Stark scoop and thermopair add 232.35g (2.001mol) levulinic acid and (derive from the Langfang Triple Well Chemicals Company of Chinese Hebei province Langfang City; Ltd.); 310mL (4.049mol) Virahol (derive from Thermo Fisher Scientific of Waltham, MA), the 600mL toluene (deriving from Thermo Fisher Scientific) and the 2mL vitriol oil.Be reflected at and be heated to backflow on the heating mantles.After backflow is spent the night, collect the water of about 31mL, and remove from the Dean-Strap scoop.Reaction flask allows to be cooled to room temperature.The 100g alkali alumina (derives from Sigma-Aldrich Company of St.Louis, MO) adds reaction soln and stir 2h then.Filter out solid then, will filtrate on rotatory evaporator concentrates, and the flask that contains filtrating is immersed in the oil bath and 20 holder vacuum tightnesss that is set at 70 ℃, to remove toluene and Virahol.Residue distills in the flask that is being immersed in the oil bath that is set at 100 ℃ and 8-10 holder vacuum tightness on the rotatory evaporator, in catching flask, to produce the 270.26g colourless liquid.Product is confirmed as 99.98% levulinic acid isopropyl ester through GC-MS.

Use Virahol and levulinic acid isopropyl ester, the method for embodiment 1 is used to produce the boiling point performance.The boiling point of measuring is shown in table 4.

The boiling point of table 4. Virahol/levulinic acid isopropyl ester mixture

Magnetic stirring bar is housed; Tap funnel; The 500mL 3 neck flasks of condensing surface and thermopair add 100.01g (0.632mol) levulinic acid isopropyl ester, and 16.08g (0.268mol) Virahol (calibrating, derive from Thermo Fisher Scientific of Waltham; MA), the 1.463mL zero(ppm) water and the 0.575mL vitriol oil.With mixture heating up in heating mantles 110 ℃ of gentle reflux.49.13g (0.496mol) furfuryl alcohol (99%, derive from Acros Organics of Geel, Belgium) and the mixture of 42.76g (0.711mol) Virahol in 170 minutes, drop to reaction mixture.After accomplishing interpolation, reaction refluxed other 1 hour.Reaction flask allows to be cooled to room temperature then.Crude product mixture shows as homogeneous, does not observe material soluble or that be separated.The reaction mixture of about 50.07g is transferred to the 250mL flask, and uses Kugelrohr equipment in about 5-6 holder with distill under 180 ℃ the airbath temperature at the most.

After distillation, the undistilled solid total amount of staying in the flask is 1.74g, and it contains the tar residue of 0.26g sulfuric acid and 1.48g.The ratio of the amount of the amount of the tar residue that forms in the reaction and the furfuryl alcohol of adding is 12.3%.The GC-MS that as embodiment 2, carries out crude reaction product analyzes, and shows that the levulinic acid isopropyl ester is presented as 97.0%.

Embodiment 9

Magnetic stirring bar is housed; The 2L 2 neck flasks of Dean-Stark scoop and thermopair add 232.67g (2.004mol) levulinic acid and (derive from Langfang Triple Well Chemicals Company; Ltd.of China Hebei province's Langfang City); 192.47g (6.007mol) methyl alcohol (derive from VWR International of West Chester, PA), the 600mL toluene and the 2mL vitriol oil.Be reflected at and be heated to backflow on the heating mantles.After backflow was spent the night, reaction flask allowed to be cooled to room temperature.Reaction mixture is divided into two-layer.Reaction mixture is transferred to the 1L separating funnel.The bottom that contains the 50mL liquid of having an appointment is discharged from separating funnel.Top layer is collected in the 1L flask.In flask, adding about 10g alkali alumina (derives from Sigma-Aldrich Company of St.Louis, MO), and mixture is at room temperature stirred 2h.Filter out solid, will filtrate on rotatory evaporator concentrates, and the flask that contains filtrating is immersed in the oil bath that is set at 80 ℃ and applies 27 holder vacuum tightnesss, to remove toluene and methyl alcohol.Residue distills in 95 ℃ of airbath temperature and 10-15 holder vacuum tightness on Kugelrohr equipment, to produce the colourless liquid of 186.73g.Product is confirmed as 99.80% methyl ester levulinate through GC-MS.

Use the method for methyl alcohol and methyl ester levulinate embodiment 1 to be used to produce the boiling point performance.The boiling point of measuring is shown in table 5.

The boiling point of table 5. methyl alcohol/methyl ester levulinate mixture

Magnetic stirring bar is housed; Tap funnel; The 500mL 4 neck flasks of condensing surface and thermopair add 100.04g (0.769mol) methyl ester levulinate; 7.52g (0.235mol) methyl alcohol (derive from VWR International of West Chester, PA), the 1.463mL deionized water and the 0.575mL vitriol oil.Use heating mantles with mixture heating up to 102 ℃ of gentle reflux.49.04g (0.495mol) furfuryl alcohol (99%, derive from Acros Organics of Geel, Belgium) and 20.94g (0.654mol) methanol mixture in 83 minutes, drop to reaction mixture.After accomplishing interpolation, reaction refluxed other 1 hour.Reaction flask allows to be cooled to room temperature then.Crude product mixture shows as homogeneous, does not observe material soluble or that be separated.The reaction mixture of about 50.02g is transferred to the 250mL flask, and uses Kugelrohr equipment under about 176 ℃ of airbaths and 7-10 holder, to distill.

After distillation, the undistilled solid total amount of staying in the flask is 4.46g, and it contains the tar residue of 0.30g sulfuric acid and 4.16g.The ratio of the amount of the amount of the tar residue that forms in the reaction and the furfuryl alcohol of adding is 30.0%.The GC-MS that as embodiment 2, carries out crude reaction product analyzes, and shows that methyl ester levulinate is presented as 98.3%.

Embodiment 10

500mL 4 neck flasks are equipped with magnetic stirring bar, tap funnel, condensing surface and thermopair.Whole set protection under positive nitrogen pressure divides accumulation to prevent water.Flask adding 100.05g (0.691mol) ethyl levulinate (derive from the Langfang Triple Well Chemicals Company of Chinese Hebei province Langfang City, Ltd.), 7.60g (0.165mol) ethanol (100%; Derive from Sigma-Aldrich, St.Louis, MO); 0.575mL (0.0106mol) sulfuric acid (95-98%; Derive from Sigma-Aldrich, St.Louis, MO).Mixture is at room temperature stirred, take out equal portions and be used for analyzing.Use heating mantles with mixture heating up to 118-120 ℃.After temperature reaches 118 ℃, take out equal portions and be used for analyzing.49.18g (0.491mol) furfuryl alcohol (98%, derive from St.Louis, the Sigma-Aldrich of MO) and 28.70g (0.623mol) ethanol (200 the degree, derive from Sigma-Aldrich, St.Louis, mixture MO) dropped to reaction mixture in 99 minutes.In the interpolation process, take out two equal portions.After accomplishing interpolation, will react other 30 minutes of heating.In reaction process, reaction mixture is entirely homogeneous, does not observe tar residue, only observes gentle reflux.The temperature of reaction performance and the HPLC result of ethyl levulinate and levulinic acid are shown in table 6.

The reactivity worth of table 6. ethyl levulinate and levulinic acid concentration and HPLC result.

Be based on ethyl levulinate and the levulinic acid concentration measured in the end reaction solution, calculate the yield of ethyl levulinate from furfuryl alcohol:

Wherein:

W _{Ethyl levulinate (finally)}Be ethyl levulinate weight in the final reacting mixture (ethyl levulinate concentration multiply by total reaction weight)

W _{Ethyl levulinate (initially)}Be the ethyl levulinate weight that adds reaction, the purity of the measurement of ethyl levulinate is described

W _{Ethyl ester propionic acid (finally)}Be the levulinic acid weight in the final reacting mixture

W _{Furfuryl alcohol}Be the furfuryl alcohol weight that adds reaction, the purity of the measurement of furfuryl alcohol is described

MW _{Ethyl levulinate}It is the molecular weight of ethyl levulinate

MW _{Furfuryl alcohol}Be furfuryl alcohol molecular weight and

MW _{Levulinic acid}It is the molecular weight of levulinic acid.

Based on equality (1) and (2), furfuryl alcohol is 84.29mol% to the final transformation efficiency of ethyl levulinate, and furfuryl alcohol is 6.41% to the transformation efficiency of levulinic acid.Furfuryl alcohol is 90.70mol% to the total conversion rate of levulinic acid material.

Embodiment 11

500mL 4 neck flasks are equipped with magnetic stirring bar, tap funnel, condensing surface and thermopair.Whole set protection under positive a little nitrogen pressure divides accumulation to prevent water.Flask adding 100.04g (0.690mol) ethyl levulinate (derive from the Langfang Triple Well Chemicals Company of Chinese Hebei province Langfang City, Ltd.), 7.60g (0.165mol) ethanol (100%; Derive from St.Louis; The Sigma-Aldrich of MO), 0.36g (0.0200mol) deionized water, 0.575mL (0.0106mol) sulfuric acid (95-98%; Derive from St.Louis, the Sigma-Aldrich of MO).Mixture is at room temperature stirred, take out equal portions and be used for analyzing.Use heating mantles with mixture heating up to 115 ℃.After temperature reaches 115 ℃, take out equal portions and be used for analyzing.The mixture of 49.10g (0.491mol) furfuryl alcohol (98%, derive from Sigma-Aldrich) and 28.48g (0.618mol) ethanol (200 degree derive from Sigma-Aldrich) dropped to reaction mixture in 93 minutes then.In the interpolation process, take out two equal portions.After accomplishing interpolation, will react other 30 minutes of heating.In reaction process, reaction mixture is entirely homogeneous, does not observe tar residue, only observes gentle reflux.The temperature of reaction performance and the HPLC result of ethyl levulinate and levulinic acid are shown in table 7.

The reactivity worth of table 7. ethyl levulinate and levulinic acid concentration and HPLC result.

Use the equality 1 and 2 among the embodiment 10, furfuryl alcohol is calculated as 83.45mol% to the transformation efficiency of ethyl levulinate, and furfuryl alcohol is calculated as 8.19mol% to the transformation efficiency of levulinic acid.Furfuryl alcohol is 91.64mol% to the total conversion rate of levulinic acid material.

Embodiment 12

500mL 4 neck flasks are equipped with magnetic stirring bar, tap funnel, condensing surface and thermopair.Whole set protection under positive nitrogen pressure divides accumulation to prevent water.Flask adds 100.07g (0.691mol) ethyl levulinate and (derives from the Langfang Triple Well Chemicals Company of Chinese Hebei province Langfang City; Ltd.), and 7.60g (0.165mol) ethanol (100%, derive from St.Louis; The Sigma-Aldrich of MO); 1.46g (0.0812mol) water, 0.575mL (0.0106mol) sulfuric acid (95-98% derives from Sigma-Aldrich).Mixture is at room temperature stirred, take out equal portions and be used for analyzing.Use heating mantles with mixture heating up to 108 ℃.After temperature reaches 108 ℃, take out equal portions and be used for analyzing.49.10g (0.491mol) mixture of furfuryl alcohol (98%, derive from Sigma-Aldrich) and 28.54g (0.619mol) ethanol (200 degree derive from Sigma-Aldrich) dropped to reaction mixture in 125 minutes.In the interpolation process, take out two equal portions.After accomplishing interpolation, will react other 30 minutes of heating.In reaction process, reaction mixture is entirely homogeneous, does not observe tar residue, only observes gentle reflux.The temperature of reaction performance and the HPLC result of ethyl levulinate and levulinic acid are shown in table 8.

The reactivity worth of table 8. ethyl levulinate and levulinic acid concentration and HPLC result.

Use the equality 1 and 2 among the embodiment 10, furfuryl alcohol is calculated as 78.73mol% to the transformation efficiency of ethyl levulinate, and furfuryl alcohol is calculated as 12.22mol% to the transformation efficiency of levulinic acid.Furfuryl alcohol is 90.95mol% to the total conversion rate of levulinic acid material.

Embodiment 13

2L 4 neck flasks are equipped with magnetic stirring bar, tap funnel, condensing surface and thermopair.Whole set protection under positive nitrogen pressure divides accumulation to prevent water.Flask adds 600.10g (4.142mol) ethyl levulinate and (derives from the Langfang Triple Well Chemicals Company of Chinese Hebei province Langfang City; Ltd.); 46.36g (1.006mol) ethanol (100%, derive from the Sigma-Aldrich Company of St.Louis, MO); 3.45mL (0.0647mol) sulfuric acid (95-98% derives from Sigma-Aldrich).Use heating mantles with mixture heating up to 118 ℃.After temperature reached 118 ℃, the mixture of 299.93g (2.996mol) furfuryl alcohol (98%, derive from Sigma-Aldrich) and 171.68g (3.727mol) ethanol (200 degree derive from Sigma-Aldrich) added reaction mixture in 169 minutes.After accomplishing interpolation, will react other 30 minutes of heating.In reaction process, reaction mixture is entirely homogeneous, does not observe tar residue, only observes gentle reflux.The temperature of reaction performance is shown in table 9.The gross weight of crude product mixture is 1122.40g.Reacted mass loss is 2.02g, and the crude mixture of taking-up 0.71g is used for analyzing.

Table 9. temperature of reaction performance.

Add the 112.5g Sodium phosphate, dibasic in the mixture in reaction flask and (derive from Thermo Fisher Scientific of Waltham, MA).Mixture is stirred 30min at 90 ℃, allow to be cooled to room temperature then.Remove solid through suction filtration.The filtrating of recovery total 1074.37g.Filtrating is transferred to 2L 4-neck round-bottomed flask.The gross weight of the filtrating of shifting is 1072.25g.With in the flask of filtrating from be set at 90 ℃ oil bath and the vacuum tightness that applies about 32 holders distilled about 3 hours.The weight of first distillment is 84.83g.First distillment is 2.5 weight % ethyl levulinates, residual ethanol, and this confirms through GC-FID.Residue uses the short-path distillation setting and is heated to 120 ℃ to 154 ℃ oil bath and distilled about 2.5 hours down in vacuum (4-7 holder) in the round-bottomed flask then.Collect the after-fractionating thing of 920.18g altogether.The gross weight of black tar residue residue is 48.65g.Mass loss is 18.59g after distillation.Through acidometric titration and GC-FID, the after-fractionating thing contains the ethyl levulinate of 97.6 weight % and the levulinic acid of 0.7 weight %.

Based on the amount of ethyl levulinate in first and second distillments that merge, and use the equality 1 and 2 among the embodiment 10, furfuryl alcohol is calculated as 70.6mol% to the conversion percentage of ethyl levulinate.

Embodiment 14

2L 4 neck flasks are equipped with magnetic stirring bar, tap funnel, condensing surface and thermopair.Whole set protection under positive nitrogen pressure divides accumulation to prevent water.Flask adds 600.09g (4.142mol) ethyl levulinate and (derives from the Langfang Triple Well Chemicals Company of Chinese Hebei province Langfang City; Ltd.); 46.35g (1.006mol) ethanol (100%; Derive from St.Louis, the Sigma-Aldrich Company of MO) and 3.45mL (0.0647mol) sulfuric acid (95-98% derives from Sigma-Aldrich).Use heating mantles with mixture heating up to 118 ℃.After temperature reached 118 ℃, the mixture of 300.59g (3.003mol) furfuryl alcohol (98%, derive from Sigma-Aldrich) and 171.76g (3.728mol) ethanol (200 degree derive from Sigma-Aldrich) was added dropwise to reaction mixture in 150 minutes.After accomplishing interpolation, will react other 30 minutes of heating.In reaction process, reaction mixture is entirely homogeneous, does not observe tar residue, only observes gentle reflux.The temperature of reaction performance is shown in table 10.The gross weight of crude product mixture is 1125.14g.Reacted mass loss is 2.44g.

Table 10. temperature of reaction performance.

(574.62g) is transferred to tap funnel with a part of crude product mixture.Tap funnel assembling 250mL 3-neck round-bottomed flask.Flask is equipped with stirring rod, splashproof adapter, static head adapter and reception flask.Flask heats in being set at 150 ℃ the oil bath of temperature.Drips of solution in the tap funnel adds to round-bottomed flask.Use heating mantles heating flask, when following temperature of 10-15 holder is 110-115 ℃, collect first distillment.Altogether after 6 hours 45 minutes, accomplish and add and distillation.The gross weight of first distillment is 508.31g.Residual tar residue gravimetry is 23.69g in the flask.Distillation back mass loss is 42.62g.Based on titration and GC-FID result, distillment is the ethyl levulinate of 97.2 weight % and the levulinic acid of 1.0 weight %.

Use the calculation result shown in the embodiment 10, the yield of ethyl levulinate is confirmed as 84.9mol%.

The middle 55g Sodium phosphate, dibasic that adds of reaction mixture (547.03g) residual in reaction flask (derives from Thermo Fisher Scientific of Waltham, MA) with 20g SODIUM SULPHATE ANHYDROUS 99PCT (deriving from Sigma-Aldrich).Mixture is stirred 30min down at 90 ℃, and allow to be cooled to room temperature.Remove solid through suction filtration.Reclaim the filtrating of 519.77g altogether.Filtrating is transferred to tap funnel.Tap funnel assembling 250mL 3-neck round-bottomed flask.Flask is equipped with stirring rod, splashproof adapter, static head adapter and reception flask.Flask heats in being set at 150 ℃ the oil bath of temperature.Drips of solution in the tap funnel adds to round-bottomed flask.When about 10 105 ℃ of following Wen Weiyue of holder, collect the after-fractionating thing.Behind 6h 14min, accomplish and add and distillation.The weight of after-fractionating thing is 462.05g.Residual tar residue gravimetry is 20.34g in the flask.After the distillation altogether mass loss be 36.99g.Based on titration and GC-FID result, the after-fractionating thing contains the ethyl levulinate of 96.4 weight % and the levulinic acid of 1.5 weight %.

Use the calculation result shown in the embodiment 10, the yield of ethyl levulinate is confirmed as 73.3mol%.

Embodiment 15

1L, 3 neck round-bottomed flasks are equipped with head space formula whisking appliance, condensing surface and liquid header and thermopair.Whole set protection under positive nitrogen pressure divides accumulation to prevent water.Flask adding 501.8g (4.395mol) ethyl levulinate (derive from the Langfang Triple Well Chemicals Company of Chinese Hebei province Langfang City, Ltd.), 53.0g (1.150mol) ethanol (100%; Derive from Sigma-Aldrich, St.Louis, MO); 2.95g (0.0301mol) and sulfuric acid (95-98%; Derive from Sigma-Aldrich, St.Louis, MO).Use heating mantles with mixture heating up to 118 ℃.After temperature reaches 118 ℃; 252.1g (2.518mol) furfuryl alcohol (98%; Derive from Sigma-Aldrich) and the mixture of 148.6g (3.226mol) ethanol (200 degree, derive from Sigma-Aldrich) in about 100 minutes, add reaction mixture with the speed of 4mL/min through the HPLC pump.After accomplishing interpolation, will be reflected at other 30 minutes of 118 ℃ of heating.In heat-processed, collect the condensation product of about 50g.Reaction mixture is entirely homogeneous, and does not have observable tar residue.Final sample weight is 895.7g.Reacted total mass loss is 62.75g.Crude product mixture is a black liquor.The HPLC of crude product mixture shows that compsn contains the ethyl levulinate of 84.2 weight % and the levulinic acid of 3.3 weight %.

The crude product mixture of about 100g is placed the rotatory evaporator under the 100 holder vacuum tightnesss.Slowly heat, after oil bath temperature reaches 181 ℃, distillation sample body.The final weight of retained material is 9.7g in the flask.Retained material is a viscosity, the tar-like material, and it is a sluggish flow under the room temperature.Distillment is a water sample liquid.

The present invention can comprise any element that discloses or quote suitably, constituted, perhaps is made up of any element open or that quote basically by any element open or that quote.The schematic disclosed the present invention of this paper can be suitably implement under the situation of clear and definite disclosed any element lacking this paper.Above-mentioned various embodiment only provides through the mode of signal, and should not be construed the restriction appended claims.To recognize,, under the situation of true spirit that does not depart from appended claims and scope, can carry out various modifications and change according to exemplary and the application that this paper describes and shows.

Claims

1. the method for a synthesis of acetyl alkyl propionates, this method comprises:

I. alkyl alcohol,

Ii protic acid catalyzer and

Said second mixture comprises:

J. furfuryl alcohol and

Iii. the said alkyl alcohol of said first mixture of additional content; And

2. the described method of claim 1, wherein said levulinic acid alkyl ester at high temperature forms.

3. the described method of claim 2, wherein said second mixture contacts said first mixture, and said first mixture keeps at high temperature.

4. the described method of claim 1, wherein said alkyl alcohol is a methyl alcohol, ethanol, n-propyl alcohol, Virahol or propyl carbinol.

5. the described method of claim 1, the mol ratio of alkyl alcohol and levulinic acid alkyl ester is about 1: 20 to 1: 1 in wherein said first mixture.

6. the described method of claim 4, the mol ratio of alkyl alcohol and levulinic acid alkyl ester is about 1: 8 to 1: 2 in wherein said first mixture.

7. the described method of claim 4, the mol ratio of alkyl alcohol and levulinic acid alkyl ester is about 1: 6 to 1: 3 in wherein said first mixture.

8. the described method of claim 1, wherein said protic acid catalyzer is a sulfuric acid, comprises sulfonic Zeo-karb, alkyl-aromatic sulfonic acid, aromatic sulfonic acid or aliphatic sulfonic.

9. the described method of claim 8, the furfuryl alcohol that wherein provides in every mole said second mixture will about 1x10 ^-4To 2.5x10 ^-2The sulfuric acid of mole adds said first mixture.

10. the described method of claim 8, the furfuryl alcohol that wherein provides in every mole said second mixture will about 2.5x10 ^-3To 2.5x10 ^-2The sulfuric acid of mole adds said first mixture.

11. the described method of claim 8, the furfuryl alcohol that wherein provides in every mole said second mixture will about 1x10 ^-2To 2x10 ^-2The sulfuric acid of mole adds said first mixture.

12. the described method of claim 1, wherein said first mixture comprises water in addition.

13. the described method of claim 12, there is about 1x10 in the furfuryl alcohol that wherein provides in every mole said second mixture ^-4Water to 0.2 mole.

14. the described method of claim 12, there is about 1x10 in the furfuryl alcohol that wherein provides in every mole said second mixture ^-3Water to 0.1 mole.

15. the described method of claim 12, there is about 1x10 in the furfuryl alcohol that wherein provides in every mole said second mixture ^-3To 5x10 ^-2The water of mole.

16. it is about 1 to 2 that the described method of claim 1, wherein said second mixture comprise the mol ratio of the mole number of furfuryl alcohol and alkyl alcohol.

17. it is about 1: 1.125 to 1: 1.75 that the described method of claim 1, wherein said second mixture comprise the mol ratio of the mole number of furfuryl alcohol and alkyl alcohol.

18. it is about 1: 1.20 to 1: 1.50 that the described method of claim 1, wherein said second mixture comprise the mol ratio of the mole number of furfuryl alcohol and alkyl alcohol.

19. the described method of claim 3, wherein said reaction mixture at high temperature stirs.

20. the described method of claim 19, wherein said alkyl alcohol are ethanol and said high temperature is about 95 ℃ to 160 ℃.

21. the described method of claim 20 also is included in said contact and heats said first mixture before.

22. the described method of claim 21, wherein said heating comprise that elevated temperature is on the boiling point of said alkyl alcohol.

23. the described method of claim 22, wherein said temperature than the boiling point height of said alkyl alcohol at least about 20 ℃.

24. the described method of claim 22, wherein said temperature than the boiling point height of said alkyl alcohol at least about 40 ℃.

25. the described method of claim 2, wherein said method is a batch process, and said second mixture contacts and after said first mixture is accomplished said high temperature kept about 1 to 60 minute.

26. the described method of claim 2, wherein said method is a batch process, and said second mixture contacts and after said first mixture is accomplished said high temperature kept about 30 minutes.

27. the described method of claim 1, the mole number of alkyl alcohol is selected according to following formula in wherein said second mixture

D＝(1+(B/A))*C

Wherein

A representes the mole number of levulinic acid alkyl ester;

B representes the mole number of alkyl alcohol in said first mixture;

C representes the mole number of furfuryl alcohol; And

D representes the mole number of alkyl alcohol in said second mixture.

28. the described method of claim 27, the mole number of alkyl alcohol is selected as pact (0.9) (D) to D in wherein said second mixture.

29. the described method of claim 1, wherein with the ratio of about 1 to the 5 mole of % of alkyl alcohol in said first mixture of every mole of PM, furfuryl alcohol contacts the alkyl alcohol in the said reaction mixture.

30. the described method of claim 1, wherein said contact comprise through hole said second mixture is added said first mixture, said hole does not contact said first mixture.

31. the described method of claim 30, wherein said hole comprises nozzle, and this nozzle is constructed to make streamed said second mixture of branch of the smog that comprises drop or fine spraying to contact the surface of said first mixture.

32. the described method of claim 1, wherein said method is a successive.

33. the described method of claim 1, wherein said reaction mixture keeps under high pressure.

34. the described method of claim 33, wherein said high pressure are to being higher than about 1 normal atmosphere of ambient pressure greater than ambient pressure.

35. the described method of claim 1, the yield of wherein said levulinic acid alkyl ester be the furfuryl alcohol in said second mixture mole number at least about 70 moles of %.

36. the described method of claim 1 also is included in and forms the said acid catalyst of levulinic acid alkyl ester post neutralization.

37. the described method of claim 36, wherein said neutralization realizes through oxyhydroxide, carbonate, supercarbonate, phosphoric acid salt, tertiary amine or the carboxylate salt of alkali or earth alkali metal.

38. the described method of claim 1 also comprises and collects the levulinic acid alkyl ester that forms.

39. the described method of claim 38, wherein said collection comprises the evaporation of alkyl alcohol, the distillation of said levulinic acid alkyl ester; Soluble reaction products is decant in the soluble reaction products never; Soluble reaction product is filtered from soluble reaction products, and liquid liquid separates, or its combination.

40. the described method of claim 39, wherein said distillation comprises vacuum distilling.

41. comprising, the described method of claim 39, wherein said distillation change film evaporation or falling film evaporation.

42. the described method of claim 38, wherein said being collected in two steps realized.

43. the described method of claim 42, wherein said two steps comprise: the first step comprises the evaporation of alkyl alcohol; And second the step, comprise the evaporation of levulinic acid alkyl ester.

44. the described method of claim 42, wherein the first step comprises the evaporation of the levulinic acid alkyl ester of alkyl alcohol and first part, and second step comprised the levulinic acid alkyl ester of removing second section.

45. the described method of claim 42 also is included in the said the first step and between said second step tar residue softening agent is added said reaction mixture.

46. the described method of claim 45, wherein said tar residue softening agent is a biodiesel fuel, 2; 2,4-trimethylammonium-1,3-pentane-glycol diisobutyrate; Tridecyl alcohol, wherein alkyl has the bialkyl ortho phthalate of 4 to 14 carbon independently, and wherein alkyl has the hexanodioic acid dialkyl of 4 to 14 carbon independently; Wherein alkyl has the DAS di alkyl sebacate of 4 to 14 carbon independently; Wherein alkyl has the mono benzoate of 4 to 14 carbon, and wherein alkyl has the dialkyl cyclic capronate of 4 to 14 carbon independently, and wherein alkyl has the tri trimellitate alkyl ester of 4 to 14 carbon independently; Wherein alkyl has the citric trialkyl ester of 4 to 14 carbon independently, or its combination.

47. the described method of claim 1, the by product that wherein comprises levulinic acid by esterification to form the levulinic acid alkyl ester.

48. the described method of claim 1, wherein after formation the merging yield of levulinic acid alkyl ester and levulinic acid be the furfuryl alcohol that provides in said second mixture mole number at least about 70 moles of %.

49. the described method of claim 38, wherein the levulinic acid alkyl ester greater than the formation of 75 weight % is collected as purified product.

50. the described method of claim 38, wherein the levulinic acid alkyl ester greater than the formation of 90 weight % is collected as purified product.

51. the method for a synthesis of acetyl alkyl propionates, this method comprises:

A. form first mixture, said first mixture comprises:

I. alkyl alcohol,

Ii protic acid catalyzer and

J. furfuryl alcohol and

With

E. reclaim said levulinic acid alkyl ester,

D＝(1+(B/A))*C

Wherein

A representes the mole number of levulinic acid alkyl ester;

B representes the mole number of alkyl alcohol in said first mixture;

C representes the mole number of furfuryl alcohol; And

D representes the mole number of alkyl alcohol in said second mixture.

52. the described method of claim 51, wherein said alkyl alcohol is a methyl alcohol, ethanol, Virahol, n-propyl alcohol or propyl carbinol.

53. the described method of claim 51, wherein said alkyl alcohol is an ethanol.

54. the described method of claim 51 also is included in said collection neutralisation of sulphuric acid before.