HK1149544A - Glycerol-based product, process for obtaining same and use thereof in the manufacture of dichloropropanol - Google Patents

Description

Glycerol-based product, method for obtaining same and use thereof in the production of dichloropropanol

The present patent application claims the benefit of french patent application FR07/59891, filed on 17.12.2007, the content of which is incorporated herein by reference.

Technical Field

The invention relates to a product based on glycerol (1, 2, 3-propanetriol), to a process for obtaining it and to the use of the product in the production of dichloropropanol, and of derived products such as epichlorohydrin and products derived from epichlorohydrin.

Background

For example, dichloropropanol is a reaction intermediate in the production of epichlorohydrin and epoxy resins (Kirk-Othmer Encyclopedia of Chemical Technology, fourth edition, 1992, Vol.2, p.156, John Wiley & Sons Inc.).

Dichloropropanol can be obtained in particular by hypochlorination of allyl chloride, by chlorination of allyl alcohol and by hydrochlorination of glycerol, according to known methods. The latter process shows the advantage that dichloropropanol can be obtained starting from fossil raw materials or renewable raw materials and that the petrochemical natural resources from which fossil materials available on earth, such as oil, gas or coal, are known to be limited.

Known methods have resulted in nitrogen-based productsProblems that accumulate in the different steps of the process for manufacturing dichloropropanol, more particularly in the recycle stream and in the purge of said stream. These nitrogen-containing compounds promote the formation of Nitrogen Oxides (NO) in certain treatments of the stream, such as High Temperature Oxidation (HTOs)_x)。NO_xMake it necessary to equip these operations with a unit for eliminating these NO_x. This is because of NO_xPromoting the formation of photochemical smog, an important form of atmospheric pollution, and acid rain.

Disclosure of Invention

The present invention aims to solve this problem by providing a novel glycerol-containing product which does not cause the above-mentioned problems when used in a process for the production of dichloropropanol.

The invention therefore relates to a product comprising glycerol and at least one nitrogen-containing compound and in which the total content of nitrogen-containing compounds expressed as elemental nitrogen (N) is less than or equal to 1g N/kg of product.

According to the invention molecular nitrogen N₂Is not a nitrogen-containing compound.

One of the main features of the present invention is the low content of nitrogen-containing compounds in the glycerol-containing product. The use of a product comprising glycerol and a low content of nitrogen-containing product according to the invention for the production of dichloropropanol has the advantage of avoiding the accumulation of nitrogen-containing products in the different steps of the process, more particularly in the recycle stream, and in the purge of said stream. The low content of nitrogen-containing compounds in the purge allows them to be treated in a High Temperature Oxidation (HTO) process to reduce the production of nitrogen oxides. This makes it possible to reduce the size of an abatement unit for the nitrogen oxides at the outlet of the HTO process, or even to eliminate such a unit completely.

In the products according to the invention, the content of glycerol is generally greater than or equal to 500g of glycerol per kg of product, preferably greater than or equal to 750g/kg, more preferably greater than or equal to 900g/kg, even more preferably greater than or equal to 950g/kg and most particularly preferably greater than or equal to 990 g/kg.

In the product according to the invention, the nitrogen-containing compound may be an inorganic compound or an organic compound. The expression "inorganic compound" is understood to mean a compound whose molecule does not comprise carbon-carbon bonds or carbon-hydrogen bonds. The expression "organic compound" is understood to mean a compound whose molecule comprises at least one carbon-carbon bond or one carbon-hydrogen bond.

The inorganic nitrogen-containing compound may be selected from ammonia, hydrazine, chloramines, inorganic ammonium salts, metallic or ammonium nitrates, nitrites, cyanates, isocyanates or isothiocyanates and mixtures thereof.

The organic nitrogen-containing compound may be selected from nitrogen-containing compounds present in cells of plant origin, preferably amines, ureas, proteins, peptides, amino acids, nucleic acids, glucosinolates and their degradation products (isothiocyanates, thiocyanates, nitriles, oxazolidinethiones), nitrogen-containing phospholipids, chlorophylls, sinapine and mixtures thereof.

Examples of nitrogen-containing phospholipids are lecithin phosphate, phosphatidylserine and phosphatidylethanolamine.

Examples of free amino acids or amino acids that can be incorporated into the peptide or protein composition are alanine, arginine, aspartic acid, cystine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine and valine.

Examples of glucosinolates are sinapioside, glucogenuinin, gluco-4-pentenyl isothiocyanate, sesamin (glucoraurin), glucoberteroin, glucoraphanin, watercresin, protopanacidin, napoleiferin, glucobrassinoside and neoglucobrassinolide.

The nitrogen-containing compound may originate from a glycerol production process, for example from vegetable oils used for the production of glycerol or also from steam corrosion inhibitors, it being possible for certain heating operations to take place by direct steam injection into, for example, the oil or glycerol. These corrosion inhibitors are generally hydrazines or amines, such as, for example, isopropylamine.

The total content of nitrogen-containing compounds expressed as elemental nitrogen in the product according to the invention is preferably less than or equal to 0.5g N/kg, more preferably less than or equal to 0.1g N/kg, even more preferably less than or equal to 0.05g N/kg, still more preferably less than or equal to 0.03g N/kg, and most particularly preferably less than or equal to 0.01g N/kg. This content is generally greater than or equal to 0.1mg N/kg.

The glycerol-based product according to the invention generally comprises glycols, generally comprising at least one diol, as described in application FR 07/56125 in the name of Solvay SA, from page 1, line 18 to page 2, line 7, the content of which is incorporated herein by reference.

The diol is preferably selected from 1, 2-ethanediol (ethylene glycol), 1, 2-propanediol (propylene glycol), 1, 3-propanediol, 1, 2-butanediol, 2, 3-butanediol, 1, 4-butanediol or a mixture of at least two thereof. 1, 3-propanediol is particularly preferred.

In the glycerol-based product according to the invention, the content of glycols is generally greater than or equal to 0.001g of glycol per kg of product and less than or equal to 100g of glycol per kg of product. This content is often less than or equal to 90g/kg, often less than or equal to 50g/kg, frequently less than or equal to 10g/kg, often less than or equal to 1g/kg, often less than or equal to 0.5g/kg and frequently less than or equal to 0.2 g/kg. The amount is often greater than or equal to 0.005g/kg, often greater than or equal to 0.01g/kg, often greater than or equal to 0.04g/kg and often greater than or equal to 0.1 g/kg.

The glycerol-based product according to the invention generally comprises glycerol alkyl ethers, generally comprising at least one glycerol alkyl ether, as described in application WO2007/144335 in the name of Solvay SA, from page 2, line 6 to page 3, line 25, the content of which is incorporated herein by reference. The glycerol methyl ethers are preferred.

The content of glycerol alkyl ethers is generally less than or equal to 90g/kg, frequently less than or equal to 50g/kg, frequently less than or equal to 10g/kg, frequently less than or equal to 5g/kg, generally less than or equal to 1g/kg, more frequently less than or equal to 0.5g/kg and more frequently less than or equal to 0.2 g/kg. This content is generally greater than or equal to 0.005g/kg, frequently greater than or equal to 0.01g/kg, frequently greater than or equal to 0.04g/kg and more frequently greater than or equal to 0.1 g/kg.

The glycerol-based product according to the invention may also comprise monoalcohols, generally comprising at least one monoalcohol, as described in application WO2007/144335 in the name of Solvay SA, from page 3, line 26 to line 31, the content of which is incorporated herein by reference.

These monoalcohols are generally present in a content of greater than or equal to 0.001g/kg of product and often greater than or equal to 0.01 g/kg. This content is generally less than 20g/kg of product and often less than or equal to 2g/kg of product.

The glycerol-based product according to the invention may also comprise water in an amount generally greater than or equal to 0.1g/kg and less than or equal to 100 g/kg. This amount is often less than or equal to 50g/kg and more preferably less than or equal to 20 g/kg.

The glycerol-based product according to the invention may also comprise alkyl esters of fatty acids, typically comprising at least one alkyl ester of fatty acids; glycerolipids, generally including at least one glyceride; and salts, often comprising at least one salt, as described in application WO2007/144335 in the name of Solvay SA, from page 5, lines 12 to 20.

These esters are generally present in a content of greater than or equal to 0.1g/kg of product, often greater than or equal to 1g/kg and often greater than or equal to 5 g/kg. This content is generally less than 50g/kg of product, and often less than or equal to 30g/kg of product, and more often less than or equal to 10g/kg of product.

These salts are generally present at levels of greater than or equal to 0.0005g/kg of product, often greater than or equal to 0.001g/kg and often greater than or equal to 0.01 g/kg. This level is generally less than 10g/kg of product, and often less than or equal to 1g/kg of product, and more often less than or equal to 0.1g/kg of product.

These glycols, glycerol alkyl ethers, monoalcohols, water, alkyl esters of fatty acids, glycerol esters and salts may be by-products of the glycerol production process, such as for example processes for the conversion of oils or fats of vegetable or animal origin by transesterification, saponification or hydrolysis.

The glycerol-based product according to the invention can be obtained starting from fossil raw materials or renewable raw materials, preferably renewable raw materials, as described in WO2005/054167 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages from page 1, line 26, to page 4, line 2.

The glycerol-based product according to the invention can also be obtained starting from fossil raw materials or renewable raw materials, preferably renewable raw materials, as described in WO2006/100312 of SOLVAY SA, the content of which is incorporated herein by reference, and in particular the passages from page 3, line 29, to page 5, line 24.

The glycerol-based product according to the invention can also be obtained starting from fossil raw materials or renewable raw materials, preferably renewable raw materials, as described in PCT/EP2008/057876 of SOLVAY SA, the content of which is incorporated herein by reference, and in particular in the passages on page 10, lines 16 to 23, and on page 11, lines 4 to 25.

The glycerol-based product according to the invention may have an alkali metal and/or alkaline earth metal content as described in WO2006/100315 of SOLVAY SA, the content of which is incorporated herein by reference, and in particular the passages from page 7, line 11 to page 9, line 10.

The glycerol-based product according to the invention may comprise elements other than alkali and alkaline earth metals, as described in WO 2006/100319 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages from page 2, lines 3 to 8 and from page 6, line 20 to page 9, line 14.

The glycerol-based product according to the invention generally comprises a quantity of heavy compounds other than glycerol having a boiling temperature at 1 bar absolute pressure at least 15 ℃ higher than the boiling temperature of dichloropropanol, as described in WO 2006/1000316 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages from page 15, line 32 to page 17, line 33.

The glycerol-based product according to the invention may comprise glycerol oligomers, as described in FR 08/52206 of SOLVAYSA, the content of which is incorporated herein by reference, especially the passages from page 1, line 19 to page 4, line 18.

The invention also relates to a process for the preparation of a glycerol-containing product and at least one nitrogen-containing compound, and in which the total content of nitrogen-containing compounds expressed as elemental nitrogen is less than or equal to 1g N/kg, comprising the following steps:

a) subjecting seeds of the plant to a pressing operation in order to obtain an oil of plant origin;

b) subjecting the vegetable oil to an operation of transesterification reaction in the presence of methanol so as to obtain glycerol comprising at least one nitrogen-containing compound, and wherein the total content of nitrogen-containing compounds expressed as elemental nitrogen is greater than 1 gN/kg; and is

c) Subjecting the glycerol-containing product from step b) to a supplementary step c), in which a portion of the glycerol obtained in step b) is subjected to at least one purification treatment so as to obtain a product comprising glycerol and at least one nitrogen-containing compound, and in which the total content of nitrogen-containing compounds expressed as elemental nitrogen is less than or equal to 1gN/kg of product.

The treatment from step c) may be carried out under reduced pressure. The treatment may be selected from the group consisting of: evaporative concentration, evaporative crystallization, distillation, fractional distillation, stripping, liquid/liquid extraction operations, and any combination of at least two thereof.

The term "evaporative concentration" is understood to mean a process in which the product is partially evaporated, which makes it possible to concentrate the residual product to a less volatile entity. The term "evaporative crystallization" is understood to mean a process which brings about the crystallization of a compound by removing, by means of evaporation, a compound which promotes its dissolution in the medium. These methods are described in section 11 of "Perry's chemical Engineers' Handbook of Perry chemistry Engineers" 7 th edition.

The term "distillation" is understood to mean the type of separation conventional in Chemical engineering and is described, for example, in section 13 of "Perry's Chemical Engineers' Handbook" 7 th edition.

The term "fractionation" is understood to mean a series of distillations in which the distillate is withdrawn batchwise.

The term "stripping" is understood to mean the separation of a substance by entrainment with the vapour of a pure material. In the process according to the invention, this material can be any compound inert to glycerol, such as, for example, steam, air, nitrogen and carbon dioxide.

The term "liquid/liquid extraction" is understood to mean the contact with a suitable, completely or partially immiscible solvent making it possible to extract selectively the desired compound, optionally according to a countercurrent process, as described in section 15 of "Perry's Chemical Engineers' Handbook" of Perry Chemical Engineers, 7 th edition.

The stripping, evaporative concentration, evaporative crystallization, liquid/liquid extraction and distillation treatments can be combined, for example in a stripping column equipped with a distillation section at the top, or in a partial evaporator providing a distillation column or by combining a liquid/liquid extraction, stripping of the residual solvent contained in the glycerol-rich stream and distillation of the solvent rich in the extracted compound.

The glycols, mono-alcohols and glycerol alkyl ethers are recovered in a distilled, evaporated or stripped fraction and the purified glycerol-based product constitutes a middle distillate fraction from the distillation, evaporation or stripping process. The major portion of these nitrogen-containing impurities constitutes the residue from the treatment.

When the treatment comprises partial evaporation of the product, the temperature of the glycerol-rich zone is generally higher than or equal to 0 ℃, often higher than or equal to 80 ℃ and often higher than or equal to 100 ℃. The temperature is generally less than or equal to 280 ℃, often less than or equal to 250 ℃, and often less than or equal to 200 ℃. The temperature in the glycerol-depleted zone is generally greater than or equal to-20 deg.C, preferably greater than or equal to-10 deg.C, particularly preferably greater than or equal to 0 deg.C. The temperature is generally at most equal to the temperature of the glycerol-rich zone, preferably at least 5 ℃ below this temperature, particularly preferably at least 10 ℃ below this temperature.

When the treatment is carried out by liquid/liquid extraction, the temperature is generally greater than or equal to 20 ℃, preferably greater than or equal to 40 ℃ and more particularly greater than or equal to 50 ℃. The temperature is generally less than or equal to 200 ℃, preferably less than or equal to 150 ℃ and more particularly preferably less than or equal to 120 ℃.

The treatment pressure is generally greater than or equal to 0.001 mbar. The pressure is generally lower than or equal to 1 bar, generally lower than or equal to 0.5 bar, frequently lower than or equal to 0.3 bar and more precisely lower than or equal to 0.25 bar. When the treatment comprises a single evaporation step, the latter is generally carried out at a pressure of less than or equal to 2 bar absolute, preferably at a pressure of less than or equal to 1 bar absolute, particularly preferably at a pressure of less than or equal to 0.5 bar absolute. Generally at a pressure greater than or equal to 0.1 mbar, preferably greater than or equal to 0.2 mbar. When the evaporation step is combined with a distillation or fractionation step, it is carried out at a pressure at least equal to that of the step carried out at the lowest pressure, preferably at a pressure at least 10 mbar higher than that of the step carried out at the lowest pressure. The stripping step is generally carried out at a pressure of less than or equal to 5 bar, preferably less than or equal to 2 bar.

In distillation processes with or without stripping, the reflux ratio is generally greater than or equal to 1%, often greater than or equal to 5% and often greater than or equal to 10%. The reflux ratio is generally less than or equal to 99% and often less than or equal to 50%. The expression "reflux ratio" is understood to mean the ratio between the flow rate of the fraction evaporated to the reboiler and the flow rate of the residue for a continuous distillation.

The expression "reflux ratio" is understood to mean, for a batchwise fractional distillation, the proportion of the amount evaporated relative to the final residue.

The amount of distillate distilled is generally less than or equal to 300g/kg, often less than or equal to 100g/kg of glycerol-based product.

The distillation, fractionation or stripping treatment may be preceded or followed by an operation which may be, for example, a settling, centrifugation, filtration, adsorption or ion exchange operation. When it is a settling operation, the operation may be improved by passing through a coalescing filter. The adsorption operation is preferably an operation of adsorption on activated carbon.

The invention also relates to a process for producing dichloropropanol in which a product comprising glycerol and at least one nitrogen-containing compound, in which the total content of nitrogen-containing compounds expressed as elemental nitrogen is less than or equal to 1g N/kg, is reacted with a chlorinating agent.

The chlorinating agent generally comprises hydrogen chloride. The hydrogen chloride may be gaseous hydrogen chloride, aqueous hydrogen chloride or a mixture of both.

The chlorinating agent is described in patent application WO2005/054167 in the name of Solvay SA, from page 4, line 32 to page 5, line 18, the contents of which are incorporated herein by reference.

In the process for manufacturing dichloropropanol according to the invention, the hydrogen chloride is often a gas or a mixture of a gas and an aqueous solution of hydrogen chloride. The hydrogen chloride may be at least partly obtained from a process such as described in WO2005/054167 of SOLVAY SA, the content of which is hereby incorporated by reference, especially the passages from page 4, line 32 to page 5, line 35.

This hydrogen chloride may be at least partly obtained from a process such as described in WO2006/106153 of SOLVAY SA, the content of which is hereby incorporated by reference, especially the passages from page 2, line 10 to page 3, line 20 and from page 11, line 1 to page 18, line 29.

This hydrogen chloride may be at least partly obtained from a process such as described in WO2007/144335 of SOLVAY SA, the content of which is incorporated herein by reference, especially the passages from page 12, line 14 to page 14, line 21.

In the process for producing dichloropropanol according to the invention, the hydrogen chloride may be purified as described in FR 08/56138 of SOLVAYSA, the content of which is incorporated herein by reference, in particular the passages from page 2, line 33 to page 16, line 21.

In the process for manufacturing dichloropropanol according to the invention, the reaction between glycerol and the chlorinating agent hydrogen chloride may be carried out in a reaction medium as described in WO 2006/106154 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages from page 14, line 15 to page 17, line 10.

The reaction with the chlorinating agent may be carried out in the presence of a catalyst, preferably a carboxylic acid or a carboxylic acid derivative, as described in patent application WO2005/054167 in the name of Solvay SA, from page 6, line 24 to page 7, line 35, the content of which is incorporated herein by reference. Succinic, glutaric, adipic, suberic, sebacic, dodecanoic, citric and butanetetracarboxylic acids and their derivatives such as acid chlorides, anhydrides, esters and salts are examples of catalysts. Nitrogen-containing carboxylic acid derivatives, such as, for example, amides and nitriles, are not considered to be carboxylic acid derivatives that can be used as catalysts.

The reaction with the chlorinating agent may be carried out with catalyst concentration, temperature, pressure and residence time as described in WO2005/054167 of SOLVAY SA, the content of which is herein incorporated by reference, especially the passages from page 8, line 1 to page 10, line 10.

The reaction with the chlorinating agent may be carried out as described in WO 2007/054505 of SOLVAY SA, the content of which is herein incorporated by reference, especially the passages from page 1, line 24 to page 6, line 18.

The process for producing dichloropropanol according to the invention may be carried out in plants made of or coated with materials resistant to corrosion by the chlorinating agent under the process conditions, as described in WO2005/054167 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages from page 6, line 3 to line 23.

The process for producing dichloropropanol according to the invention may be carried out in plants made of or coated with materials resistant to corrosion by the chlorinating agent under the process conditions, as described in WO 2006/100317 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages from page 23, line 22 to page 27, line 25.

The process for producing dichloropropanol according to the invention may be carried out in plants made of or coated with materials that are resistant to corrosion by the chlorinating agent under the process conditions, as described in PCT/EP2008/062845 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages from page 1, line 30 to page 9, line 17, and from page 19, line 25 to page 20, line 33.

The chlorination reaction is preferably carried out in a liquid reaction medium.

The chlorination reaction may be carried out in the presence of a solvent as described in WO2005/054167 of SOLVAY SA, the content of which is incorporated herein by reference, especially in the passages on page 11, line 12 to line 36.

However, the solvent may not contain nitrogen in its molecule.

The reaction with the chlorinating agent may be carried out in the presence of a liquid phase comprising heavy compounds other than glycerol, as described in WO 2006/100316 of SOLVAY SA, the content of which is incorporated herein by reference, especially in the passages from page 2, line 18 to line 25 and from page 15, line 32 to page 17, line 33. Heavy nitrogen-containing compounds are not considered as heavy compounds that may be present in the liquid phase.

The reaction with the chlorinating agent may be carried out under stirring in a stirring system as described in PCT/EP2008/056688 of SOLVAYSA, the content of which is incorporated herein by reference, in particular the passages from page 1, 30 to page 2, line 33 and from page 6, line 22 to page 14, line 31.

The reaction with the chlorinating agent may be carried out in a liquid reaction medium, as described in WO 2006/106154 to SOLVAYSA, the content of which is incorporated herein by reference, in particular the passages from page 1, line 29 to page 2, line 6 and from page 14, line 15 to page 17, line 10.

The reaction with the chlorinating agent may be carried out in a reactor, the feed of which is as described in WO 2008/107468 to SOLVAYSA, the content of which is herein incorporated by reference, especially the passages from page 1, page 29 to page 4, line 27 and from page 5, line 34 to page 9, line 17.

The dichloropropanol formed may be separated from the other components of the reaction medium by any separation treatment, for example by distillation, stripping, extraction or adsorption. After this treatment, the other components of the reaction medium may be subjected to supplemental separation treatment and/or reused. Among the other components of the reaction medium are heavy products, such as, for example, chlorinated and/or esterified isomers of different glycerol oligomers.

In the process for producing dichloropropanol according to the invention, the separation of the dichloropropanol from the other compounds of the reaction mixture may be carried out as described in WO2005/054167 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages from page 12, line 1 to page 17, line 20.

In the process for producing dichloropropanol according to the invention, the separation of the dichloropropanol from the other compounds of the reaction mixture may be carried out as described in WO2006/100312 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages on page 2, line 3 to line 10, on page 20, line 28 to page 28, line 20.

In the process for producing dichloropropanol according to the invention, the separation of the dichloropropanol from the other compounds of the reaction mixture may be carried out according to the process described in WO 2006/100313 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages on page 2, lines 1 to 23 and from page 21, line 7 to page 25, line 25.

In the process for producing dichloropropanol according to the invention, the separation of the dichloropropanol from the other compounds of the reaction mixture may be carried out according to the process described in WO 2006/100314 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages on page 2, line 6 to page 3, line 4, and from page 18, line 33 to page 22, line 29.

In the process for producing dichloropropanol according to the invention, the separation of the dichloropropanol from the other compounds of the reaction mixture may be carried out according to the process described in WO 2006/100320 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages from page 1, line 30 to page 2, line 23 and from page 6, line 25 to page 10, line 28.

In the process for producing dichloropropanol according to the invention, the separation of the dichloropropanol from the other compounds of the reaction mixture may be carried out according to the process described in WO2006/100315 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages on page 2, line 3 to line 29 and from page 23, line 3 to page 24, line 13.

In the process for the production of dichloropropanol according to the invention, the separation of the dichloropropanol from the other compounds of the reaction mixture may be carried out according to the process described in WO 2008/110588 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages from page 1, line 31 to page 27, line 25.

In the process for the production of dichloropropanol according to the invention, the dichloropropanol is generally obtained as a mixture of 1, 3-dichloro-2-propanol and 2, 3-dichloro-1-propanol isomers, as described in WO 2006/100319 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages from page 23, line 34 to page 24, line 29.

Halogenated ketones may be included in the process for producing dichloropropanol according to the invention, as described in WO2006/100311 of SOLVAY SA, the content of which is incorporated herein by reference, in particular the passages from page 2, line 22 to line 34 and from page 22, line 8 to page 23, line 35.

In the process for producing dichloropropanol according to the invention, the water which has been in contact with the walls of the plant may be treated as described in FR 08/56059 of SOLVAY SA, the content of which is incorporated herein by reference, in particular in the paragraph from page 1, line 7 to page 16, line 34.

The use of a product comprising glycerol and a low content of nitrogen-containing products for the production of dichloropropanol according to the invention has the advantage of avoiding the accumulation of nitrogen-containing products in the different steps of the process, more particularly in the recycle stream, and in the purge of said stream. The low content of nitrogen-containing compounds in the purge allows them to be treated in a High Temperature Oxidation (HTO) process to reduce the production of nitrogen oxides. This makes it possible to reduce the size of an abatement unit for the nitrogen oxides at the outlet of the HTO process, or even to eliminate such a unit completely.

These nitrogen oxides, in particular NO and NO₂It can combine with Volatile Organic Compounds (VOCs) in the presence of sunlight to form a photochemical smog, an important form of atmospheric pollution, especially in summer. These nitrogen oxides may also dissolve in atmospheric moisture to form nitric acid, a component of acid rain.

The present invention also relates to a process in which the dichloropropanol obtained according to the process for the production of dichloropropanol of the invention is subjected to a dehydrochlorination reaction in order to obtain epichlorohydrin.

In this process, another portion of the dichloropropanol may be obtained by a process other than glycerol chlorination. The process may be selected from allyl chloride hypochlorination and allyl alcohol chlorination processes.

The process for dehydrochlorinating the dichloropropanol may be as described in WO2005/054167 in the name of Solvay SA, the content of which is incorporated herein by reference, more precisely the passages from page 19, line 12 to page 22, line 30.

The process for the dehydrochlorination of dichloropropanol can be as described in WO2006/100311 in the name of Solvay SA, the content of which is incorporated herein by reference, more precisely in the passages on page 2, line 22 to line 25, and from page 22, line 28 to page 23, line 35.

The process for the dehydrochlorination of dichloropropanol may be as described in WO2008/101866 in the name of Solvay SA, the content of which is incorporated herein by reference, more precisely the passages from page 2 line 1 to page 13 line 16.

The process for the dehydrochlorination of dichloropropanol may be as described in PCT/EP2008/057247 in the name of Solvay SA, the content of which is incorporated herein by reference, more precisely the passages from page 9, line 22 to page 13, line 31.

The process for the dehydrochlorination of dichloropropanol may be as described in PCT/EP2008/057245 in the name of Solvay SA, the content of which is incorporated herein by reference, more precisely the passages from page 6, line 16 to page 7, line 22.

The process for manufacturing epichlorohydrin may be incorporated into an overall scheme for the manufacture of dichloropropanol, as described in WO 2006/106155 in the name of Solvay SA, the content of which is incorporated herein by reference, more precisely the passages on page 2, line 26 to line 31 and from page 22, line 10 to page 23, line 19.

The process for the dehydrochlorination of dichloropropanol can also be carried out as described in WO2006/100318 in the name of Solvay SA, the content of which is incorporated herein by reference, more precisely the passages from page 2, line 23 to page 3, line 26, and from page 24, line 17 to page 31, line 18.

The process for the dehydrochlorination of dichloropropanol may also comprise a step of treating the aqueous effluent, for example as described in EP 08150925.9 in the name of Solvay SA, the content of which is incorporated herein by reference, more precisely the passages from page 1, line 18 to page 12, line 10.

The invention also relates to the use of a product comprising glycerol and at least one nitrogen-containing compound, in which the total content of nitrogen-containing compounds expressed as elemental nitrogen is less than or equal to 1g N/kg, for reacting with a chlorinating agent in a process for the production of dichloropropanol. The process for the manufacture of dichloropropanol is characterized as described above.

The invention finally relates to a production process in which epichlorohydrin obtained in the process for the production of epichlorohydrin according to the invention is subjected to a reaction with:

at least one compound containing at least one active hydrogen atom, so as to obtain an epoxide derivative selected from the group consisting of: an epoxy resin, a glycidyl ether, a glycidyl ester, a glycidyl amide, a glycidyl imide or any mixture of at least two of them; or

Ammonia, amines, polyaminoamides, or polyimines, in order to obtain coagulants; or

Polyamines, polyamides or polyaminoamides, in order to obtain water-resistant resins for paper treatment; or

Amine or amine salt, so as to obtain a cationizing agent; or

A compound selected from phosphoric acid, phosphate, phosphorus oxychloride, phosphate, phosphonic acid, phosphonate, phosphinic acid, phosphinate, phosphine oxide or phosphine, in order to obtain a flame retardant; or

A mono-alcohol or an amine containing from 12 to 16 carbon atoms, the amine being selected from: linear alkylamines, branched alkylamines, cycloalkylamines, alkoxyamines, aminoalcohols, cyclic amines containing at least one nitrogen atom in the ring structure, alkylenediamines, polyetherdiamines or polyalkylenepolyamines, in order to obtain an adjuvant to be added to the detergent composition; or

Alkylene oxides, phenylene oxides, or subjected to a reaction with alkylene oxides, phenylene oxides and glycidyl ethers or to a homopolymerization reaction, so as to obtain epichlorohydrin elastomers.

The use of epichlorohydrin and epichlorohydrin may be as described in PCT/EP2008/057247 in the name of Solvay SA, the content of which is incorporated herein by reference, more precisely the passages from page 1, line 18 to page 9, line 21 and from page 31, line 31 to page 63, line 4.

The use of epichlorohydrin and epichlorohydrin may be as described in PCT/EP2008/057246 in the name of Solvay SA, the content of which is incorporated herein by reference, more precisely the passages from page 1, line 24 to page 10, line 14 and from page 13, line 3 to page 44, line 8.

Detailed Description

Example 1 (according to the invention)

Figure 1 shows a schematic view of a specific plant which has been used to carry out the process for the production of dichloropropanol according to the invention.

At 117 ℃ and a pressure of 1.14 bar absolute, a stream containing 0.02g N/kg of glycerol was continuously fed to reactor 4 via line 1, a stream of hydrogen chloride via line 2, and a stream of catalyst via line 3. A gas phase produced by the reactor 4 is supplied via line 5 to a distillation column 6; the residue from column 6 is recycled to reactor 4 via line 8. Product stream 7 comprises most of the water produced by the process and a first portion of the dichloropropanol product. A liquid purge is withdrawn from the reactor 4 through line 9 and fed to an evaporator 10, in which a partial evaporation of the mixture is carried out by heating; the gaseous phase from stream 9 comprising most of the hydrogen chloride and most of the water is recycled to the bottom of column 6 through line 11. A stripping column 13 is supplied with the liquid phase from the evaporator 10 via line 12 and with a nitrogen stream introduced via line 16; a second portion of the dichloropropanol product is collected at the top of column 13 via line 14 and the residue from column 13 is recycled to reactor 4 via line 15. The mixture flowing in line 15 is purged batchwise via line 17. The nitrogen content of the purge was 0.12g N/kg.

Claims (11)

1. A product comprising glycerol and at least one nitrogen-containing compound, and wherein the total content of nitrogen-containing compounds expressed as elemental nitrogen (N) is less than or equal to 1g of nitrogen (N)/kg of product.

2. The product according to claim 1, wherein the total content of nitrogen-containing compounds expressed as elemental nitrogen (N) is less than or equal to 0.03g of nitrogen (N)/kg of product.

3. Product according to claim 1 or 2, comprising glycerol in an amount greater than or equal to 500g/kg of product.

4. The product according to any one of claims 1 to 3, wherein the nitrogen-containing compound is selected from nitrogen-containing compounds present in cells of plant origin.

5. The product of claim 4, wherein the nitrogen-containing compound is an organic compound selected from the group consisting of: amines, ureas, proteins, peptides, amino acids, nucleic acids, glucosinolates and their degradation products (isothiocyanates, thiocyanates, nitriles, oxazolidinethiones), nitrogen-containing phospholipids, chlorophylls, sinapine and mixtures thereof.

6. Process for the preparation of a glycerol-based product according to any one of claims 1 to 5, comprising the steps of:

a) subjecting seeds of the plant to a pressing operation in order to obtain an oil of plant origin;

b) subjecting the vegetable oil to an operation of transesterification reaction in the presence of methanol so as to obtain a product comprising glycerol and at least one nitrogen-containing compound, and wherein the total content of nitrogen-containing compounds expressed as elemental nitrogen (N) is greater than 1g N/kg; and is

c) Subjecting the glycerol-containing product from step b) to a replenishing step, wherein a portion of the glycerol obtained in step b) is subjected to at least one purification treatment so as to obtain a product comprising glycerol and at least one nitrogen-containing compound, and wherein the total content of nitrogen-containing compounds expressed as elemental nitrogen (N) is less than or equal to 1g of nitrogen (N)/kg of product.

7. The process according to claim 6, wherein the purification treatment is optionally carried out under reduced pressure and is selected from: evaporative concentration, evaporative crystallization, distillation, fractional distillation, stripping, liquid/liquid extraction operations, and any combination of at least two thereof.

8. Process for the production of dichloropropanol in which a glycerol-containing product according to any one of claims 1 to 5 is reacted with a chlorinating agent.

9. Process according to claim 8, in which the dichloropropanol is subjected to a dehydrochlorination reaction in order to obtain epichlorohydrin.

10. Process according to claim 8, in which the epichlorohydrin obtained is subjected to a reaction with:

at least one compound containing at least one active hydrogen atom, so as to obtain an epoxide derivative selected from the group consisting of: an epoxy resin, a glycidyl ether, a glycidyl ester, a glycidyl amide, a glycidyl imide, or a mixture of at least two thereof; or

Ammonia, amines, polyaminoamides or polyimines, in order to obtain coagulants; or

Polyamines, polyamides or polyaminoamides, in order to obtain water-resistant resins for paper treatment; or

Amine or amine salt, so as to obtain a cationizing agent; or

A compound selected from phosphoric acid, phosphate, phosphorus oxychloride, phosphate, phosphonic acid, phosphonate, phosphinic acid, phosphinate, phosphine oxide or phosphine, in order to obtain a flame retardant; or

A mono-alcohol or an amine containing from 12 to 16 carbon atoms, the amine being selected from: linear alkylamines, branched alkylamines, cycloalkylamines, alkoxyamines, aminoalcohols, cyclic amines containing at least one nitrogen atom in the ring structure, alkylenediamines, polyetherdiamines or polyalkylenepolyamines, in order to obtain an adjuvant to be added to the detergent composition; or

Alkylene oxides, phenylene oxides, or subjected to a reaction with alkylene oxides, phenylene oxides and glycidyl ethers, or to a homopolymerization reaction, so as to obtain an epichlorohydrin elastomer.

11. Use of a glycerol-containing product according to any one of claims 1 to 5 in a process for the production of dichloropropanol.