JP4282831B2 - Production method of diols - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention uses 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol by directly hydrogenating a dicarboxylic acid mixture containing succinic acid, glutaric acid, and adipic acid without going through an esterification step. Relates to a process for producing a diol mixture comprising Diols are useful substances as raw materials for polyester resins, urethane foam, urethane paints, and adhesives.
[0002]
[Prior art]
Conventionally, many methods for producing 1,4-butanediol by hydrogenating succinic acid or maleic acid have been reported. For example, as the most well-known method, there is a method using a copper-based catalyst. However, in this method, succinic acid cannot be directly reduced, and the carboxylic acid must be once converted to an ester and then reduced, resulting in a long production process.
[0003]
On the other hand, several methods for producing 1,4-butanediol by directly reducing succinic acid or maleic acid have been proposed. When only the catalyst system is listed, a catalyst made of ruthenium-iron oxide (US Pat. No. 4,827,001), a catalyst in which ruthenium-tin is supported on porous carbon having a BET surface area of 2000 m ² / g or more (Japanese Patent Laid-Open No. Hei 5- 246915), a catalyst in which ruthenium and tin are supported on silica modified with titanium and / or alumina (Japanese Patent Laid-Open No. 6-116182), a catalyst in which ruthenium and tin, and an alkali metal compound or alkaline earth metal are supported on a support ( JP-A-6-239778), a catalyst in which at least one selected from ruthenium, platinum and rhodium and tin are supported on a carrier (JP-A-7-165644), and a catalyst in which ruthenium and tin are supported on a carrier. A method in which excess hydrogen is circulated in the reaction system and the reaction is carried out while removing entrained products out of the system (JP-A-9-12). 92), ruthenium-tin-platinum-supported catalyst (Japanese Patent Laid-Open No. 9-59190), and ruthenium prepared by impregnating activated carbon with a solution containing a supporting component in which a carbonyl compound having 5 or less carbon atoms coexists. A catalyst in which tin-platinum is supported on activated carbon (Japanese Patent Laid-Open No. 10-15388), and a catalyst in which ruthenium-tin-platinum in which the supported state of the metal is defined by using activated carbon previously contacted with nitric acid is supported on the activated carbon (Japanese Patent Laid-Open No. 10-71332) has been proposed, but in any of the methods using a catalyst, the selectivity of 1.4-butanediol, tetrahydrofuran and γ-butyrolactone is not sufficient, and the yield of 1,4-butanediol is Was unsatisfactory. Japanese Patent Laid-Open No. 7-82190 proposes a method of hydrogenation using a catalyst comprising palladium and a rhenium compound and a tertiary alcohol as a solvent, but the reaction rate is still insufficient.
[0004]
On the other hand, as an oxygen-containing C4 hydrocarbon raw material, maleic anhydride or maleic acid obtained by air oxidation of butane is suitable because it is industrially produced. However, cyclohexanone and / or cyclohexanol is oxidized to form adipine. Succinic acid contained in dicarboxylic acids by-produced when producing the acid is also a suitable raw material. That is, if an industrially useful compound can be obtained using this dicarboxylic acid as a raw material, waste generated in the production of adipic acid can be reduced, and this by-product generally includes glutaric acid and adipine in addition to succinic acid. Directly because it is expected that not only 1,4-butanediol but also industrially useful diols such as 1,5-pentanediol and 1,6-hexanediol can be co-produced because the acid is contained. Suitable as a raw material for hydrogenation.
[0005]
U.S. Pat. No. 5,698,749 states that 1,4-butanediol can be obtained from maleic acid in a relatively high yield using a catalyst supported on activated carbon that has been pretreated with nitric acid in palladium-silver-rhenium. However, nothing is described about the results of the hydroreduction reaction of glutaric acid or adipic acid. Japanese Patent Application Laid-Open No. 11-60523 describes that 1,6-hexanediol can be obtained in high yield from adipic acid using a catalyst in which ruthenium-tin-platinum is supported on activated carbon that has been previously acid-treated. However, as described above, as a result of hydrogenation of succinic acid using this catalyst described in JP-A-10-71332, it is possible to obtain 1,4-butanediol from succinic acid in a high yield. Have difficulty.
[0006]
[Problems to be solved by the invention]
The object of the present invention is to obtain 1,4-butanediol from a mixture of dicarboxylic acids containing succinic acid, glutaric acid, and adipic acid, which are by-produced when cyclohexanone and / or cyclohexanol is oxidized to produce adipic acid. , 5-pentanediol, 1,6-hexanediol It is to provide a production method for obtaining a mixture of diols in high yield.
[0007]
[Means for Solving the Problems]
As a result of intensive studies by the present inventors to solve the above-mentioned problems, surprisingly, a catalyst in which at least one metal selected from ruthenium, tin, rhenium, and molybdenum is supported on a carbonaceous support previously treated with a mineral acid is used. Thus, it has been found that 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol can be produced with good yield from a mixture of succinic acid and dicarboxylic acid containing glutaric acid and adipic acid, The present invention has been completed.
[0008]
That is, the present invention is a method for producing the following diols [1] to [7].
[1] A mixture comprising succinic acid and a dicarboxylic acid represented by the following formula (1) is reacted with hydrogen in the presence of a catalyst and water to produce a mixture comprising 1,4-butanediol and a diol represented by the following formula (2). A process for producing diols, characterized in that a catalyst prepared by supporting at least one metal selected from ruthenium, tin, rhenium and molybdenum on a carbonaceous support previously treated with a mineral acid is used as a catalyst.
HOOC-R-COOH (1)
(In the formula, R represents a saturated divalent hydrocarbon group having 3 to 20 carbon atoms)
HO—CH ₂ —R—CH ₂ OH (2)
(Wherein R is the same as R in formula (1))
[2] The process for producing a diol according to [1], wherein the mixture comprising succinic acid and the dicarboxylic acid of the formula (1) is a mixture of dicarboxylic acid containing succinic acid, glutaric acid and adipic acid.
[0009]
[3] The process for producing a diol according to [1] or [2], wherein the carbonaceous carrier is activated carbon.
[4] The process for producing a diol according to any one of [1] to [3] , wherein the mineral acid is nitric acid.
[5] The process for producing a diol according to any one of [1] to [4] , wherein the metal supported on the carbonaceous carrier is ruthenium-tin-rhenium.
[6] The mixture comprising succinic acid and the dicarboxylic acid of the formula (1) is a mixture of dicarboxylic acid containing succinic acid, glutaric acid, and adipic acid recovered from the cyclohexanone and / or cyclohexanol oxidation reaction solution. The process for producing a diol according to any one of [1] to [5].
[7] The process for producing a diol according to any one of [1] to [6] , wherein a mixture of dicarboxylic acids is reacted with hydrogen under conditions of a temperature of 100 ° C to 300 ° C and a pressure of 1 MPa to 25 MPa.
[0010]
Hereinafter, the present invention will be described in detail.
In the present invention, the raw material used for the production of diols containing 1,4-butanediol is a mixture comprising succinic acid and the dicarboxylic acid of the formula (1), and in particular, dicarboxylic acid containing succinic acid, glutaric acid and adipic acid. It is a mixture of acids. One example of such a raw material is a mixture of dicarboxylic acids by-produced when nitric acid is oxidized to cyclohexanenone and / or cyclohexanol to produce adipic acid. For example, it is a mother liquor obtained by crystallization separation of adipic acid. In the present invention, the mother liquor may be used as it is, or when the hydrogen reduction activity of the catalyst is reduced due to some impurities, it may be used after steps such as decatalysis, dehydration, and denitrification.
[0011]
The hydrogen reduction catalyst used in the present invention is prepared by supporting at least one metal selected from ruthenium, tin, rhenium and molybdenum on a carbonaceous support. As the carbonaceous support, activated carbon is preferable, but carbon black, graphite, and the like can also be used. Although there is no restriction | limiting in particular in the surface area of a carbonaceous support | carrier, What has a surface area of nitrogen adsorption-BET surface area before processing with a mineral acid of 600-2,000 m < ² > / g is preferable. In the present invention, the carbonaceous support is used for the preparation of the catalyst after pretreatment with a mineral acid in advance.
[0012]
The pretreatment with a mineral acid may be performed by adding a carbonaceous support to the mineral acid and maintaining it at room temperature or under heating for several minutes to several tens of hours. As the mineral acid, nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid and the like can be used, and nitric acid is particularly preferably used. The concentration of the mineral acid is not particularly limited, but is preferably 1 to 90% by weight, particularly 5 to 60% by weight. The treatment temperature is preferably 30 to 100 ° C, more preferably 80 to 95 ° C. The treatment time depends on the mineral acid concentration and the treatment temperature, but is at least several minutes to several tens of hours, more preferably 1 to 20 hours. The carbonaceous carrier pretreated with the mineral acid is thoroughly washed with water to remove the deposited mineral acid and used for catalyst preparation.
[0013]
As a method of supporting at least one metal selected from ruthenium, tin, rhenium, and molybdenum on a carbonaceous support pretreated with a mineral acid, it is generally used to adjust the supported catalyst such as an immersion method, an ion exchange method, and an impregnation method. Any method can be used. When the immersion method is used, a metal compound solution is prepared by dissolving a metal compound material to be supported in a solvent such as water, and the carbonaceous carrier pretreated with a mineral acid by the above method is immersed in this solution to the carrier. Support. There is no particular limitation on the order in which each metal component is supported on the carrier, and all the metals may be supported simultaneously or each component may be individually supported.
[0014]
Depending on the catalyst preparation method, the metal component materials used for catalyst preparation are usually mineral salts such as nitrates, sulfates and hydrochlorides, organic acid salts such as acetates, hydroxides, oxides and organics. A metal compound or the like can be used.
The carbonaceous support carrying the metal component is dried and then calcined and reduced as desired to form a catalyst. Drying is usually performed at a temperature of 200 ° C. or lower under reduced pressure or by passing a dry gas such as nitrogen or air. Firing is usually performed at a temperature of 100 to 600 ° C. while circulating nitrogen, air, or the like. The reduction may be performed by either liquid phase reduction or gas phase reduction.
[0015]
Usually, gas phase reduction is performed at a temperature of 200 to 500 ° C. using hydrogen as a reducing gas. The supported amount of ruthenium and tin is 0.5 to 50% by weight, preferably 1 to 10% by weight, as a metal, respectively, with respect to the support. The ratio of ruthenium and tin is an element ratio as a metal, and the ruthenium: tin ratio is preferably 1: 0.1 to 1: 2, more preferably 1: 0.2 to 1: 1. In the present invention, at least one metal selected from rhenium and molybdenum is supported in addition to ruthenium and tin, among which rhenium is particularly preferable. The supported amount of rhenium and molybdenum is preferably 0.1 to 5 and more preferably 0.2 to 2 with respect to ruthenium as an element ratio as a metal.
[0016]
In the present invention, hydrogenation reduction of a dicarboxylic acid mixture comprising succinic acid, glutaric acid, and adipic acid in the presence of a catalyst in which at least one metal selected from ruthenium, tin, rhenium, and molybdenum is supported on a carbonaceous support and water. I do. The amount of water in the reaction is 0.5 to 100 times by weight with respect to the dicarboxylic acid mixture. More preferably, it is 1 to 20 times by weight. An amount of water in which the entire amount of the dicarboxylic acid dissolves at the hydroreduction temperature is preferred. The hydrogenation temperature is preferably 50 to 400 ° C, more preferably 100 to 300 ° C. The pressure is 0.5 to 40 MPa, more preferably 1 MPa to 25 MPa.
[0017]
The reduction reaction may be carried out either continuously or batchwise. As the reaction type, either a liquid phase suspension reaction or a fixed bed flow reaction can be used.
In the present invention, a mixture of 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol is obtained as the diol. These diols can be purified by an ordinary purification method such as distillation separation as necessary. can do.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in more detail with reference to examples and the like. Of the reaction results, the conversion rate of the raw material was calculated from the analytical value of liquid chromatography, and the yield of diols was calculated from the analytical value of gas chromatography. A mixture of succinic acid, glutaric acid, and adipic acid was obtained by dehydration and denitration treatment from a mother liquor obtained by crystallization separation of adipic acid. The composition was 23% by weight of succinic acid, 60% by weight of glutaric acid, and 17% by weight of adipic acid by liquid chromatography analysis.
[0019]
[Example 1]
<Nitric acid treatment of activated carbon>
30 g of nitric acid (particle size 10 to 20 mesh, nitrogen adsorption—BET surface area 1400 m ² / g) was added to 75 g of 30% nitric acid, followed by heat treatment at 90 ° C. for 3 hours with stirring. After cooling, the activated carbon was filtered and washed with 100 ml of ion exchange water until the filtrate became neutral. The obtained activated carbon was dried with hot air at 120 ° C. for 5 hours.
<Preparation of Ru-Sn-Re catalyst>
In a 100 ml eggplant flask, 2.00 g of ion exchange water and 0.39 g of ruthenium chloride trihydrate were dissolved. To the solution, 0.20 g of tin chloride (II) dihydrate was added and dissolved. Further, 0.22 g of dirhenium heptoxide was added and dissolved. To this solution, 3.00 g of the activated carbon treated with nitric acid was added and shaken at room temperature for 15 hours. After distilling off water at 70 ° C. and 20 torr using an evaporator, it was baked at 150 ° C. for 2 hours in a nitrogen gas atmosphere, and then reduced at 450 ° C. for 2 hours in a hydrogen atmosphere. The atmosphere was again a nitrogen gas atmosphere, cooled to room temperature, and allowed to stand in a 0.1% oxygen / nitrogen atmosphere for 2 hours.
By the above method, a catalyst having 5.0 wt% ruthenium-3.5 wt% tin-5.6 wt% rhenium supported on activated carbon was prepared.
[0020]
<Hydrogen reduction reaction of succinic acid, glutaric acid, adipic acid mixture>
An autoclave with a capacity of 100 ml was charged with 10 g of water, 1 g of a mixture of succinic acid, glutaric acid and adipic acid and 0.3 g of the catalyst prepared by the above method, and after replacing the atmosphere in the autoclave with nitrogen at room temperature, 20 kg of hydrogen / Cm ^{2 was} injected and the temperature was raised to 180 ° C. When the temperature reached 180 ° C., hydrogen was injected to make 150 kg / cm ² . The hydroreduction reaction was performed at this pressure for 6 hours. After completion of the reaction, the catalyst was separated by decantation, and the catalyst was washed with purified water. The reaction liquid and catalyst washing liquid separated by decantation were combined, and the conversion rate of each dicarboxylic acid and the yield of diol were determined by analysis by liquid chromatography and gas chromatography. As a result, the conversion rates of succinic acid, glutaric acid and adipic acid were 98%, 97% and 79%, respectively, and the yields of 1,4-butanediol, 1,5-pentanediol and 1,6-hexanediol were as follows. Were 89%, 95% and 78%, respectively.
[0021]
[Example 2]
<Preparation of Ru-Sn-Mo catalyst>
A catalyst was prepared in the same manner as in Example 1 except that 0.08 g of (NH 4) 6 Mo 7 O 24 · tetrahydrate was used instead of 0.22 g of dirhenium heptoxide in Example 1.
As a result, a catalyst in which 5.0 wt% ruthenium-3.5 wt% tin-1.5 wt% molybdenum was supported on activated carbon was prepared.
<Hydrogen reduction reaction of succinic acid, glutaric acid, adipic acid mixture>
A hydrogenation reaction was carried out in the same manner as in Example 1 except that the ruthenium-tin-molybdenum / activated carbon catalyst prepared above was used as the catalyst. As a result, the conversion rates of succinic acid, glutaric acid and adipic acid were 90%, 95% and 83%, respectively, and the yields of 1,4-butanediol, 1,5-pentanediol and 1,6-hexanediol were as follows. Were 85%, 93% and 78%, respectively.
[0022]
[Comparative Example 1]
A ruthenium-tin-rhenium / activated carbon catalyst was prepared in the same manner as in Example 1 using activated carbon that had not been treated with nitric acid. Using this catalyst, the hydrogenation-reduction reaction of the dicarboxylic acid mixture was performed in the same procedure as in Example 1. As a result, the conversion rates of succinic acid, glutaric acid and adipic acid were 78%, 75% and 67%, respectively, and the yields of 1,4-butanediol, 1,5-pentanediol and 1,6-hexanediol were as follows. They were 23%, 24%, and 21%, respectively.
[0023]
【The invention's effect】
As described above, succinic acid, glutaric acid, and adipic acid are contained by using a catalyst in which at least one metal selected from ruthenium, tin, rhenium, and molybdenum of the present invention is supported on a carbonaceous support that has been previously treated with nitric acid. A diol mixture containing 1,4-butanediol, 1.5-pentanediol and 1,6-hexanediol can be produced in a high yield from a mixture of dicarboxylic acids.

Claims (7)

In a method for producing a mixture comprising 1,4-butanediol and a diol represented by the following formula (2) by reacting a mixture comprising succinic acid and the dicarboxylic acid represented by the following formula (1) with hydrogen in the presence of a catalyst and water. A process for producing diols, characterized in that a catalyst prepared by supporting at least one metal selected from ruthenium, tin, rhenium and molybdenum on a carbonaceous support previously treated with a mineral acid is used as a catalyst.
HOOC-R-COOH (1)
(In the formula, R represents a saturated divalent hydrocarbon group having 3 to 20 carbon atoms)
HO—CH ₂ —R—CH ₂ OH (2)
(Wherein R is the same as R in formula (1))  The process for producing a diol according to claim 1, wherein the mixture comprising succinic acid and the dicarboxylic acid of formula (1) is a mixture of succinic acid, glutaric acid and dicarboxylic acid containing adipic acid.  The method for producing a diol according to claim 1 or 2, wherein the carbonaceous carrier is activated carbon. The method for producing a diol according to any one of claims 1 to 3 , wherein the mineral acid is nitric acid. The method for producing a diol according to any one of claims 1 to 4 , wherein the metal supported on the carbonaceous carrier is ruthenium-tin-rhenium. The mixture comprising succinic acid and the dicarboxylic acid of the formula (1) is a mixture of dicarboxylic acid containing succinic acid, glutaric acid and adipic acid recovered from an oxidation reaction solution of cyclohexanone and / or cyclohexanol. Item 6. A process for producing a diol according to any one of Items 1 to 5. The process for producing a diol according to any one of claims 1 to 6 , wherein a mixture of dicarboxylic acids is reacted with hydrogen under conditions of a temperature of 100 ° C to 300 ° C and a pressure of 1 MPa to 25 MPa.