EP2917176A1

EP2917176A1 - Selective extraction of an omega-functionalised acid after oxidative cleavage of an unsaturated fatty acid and derivatives

Info

Publication number: EP2917176A1
Application number: EP13795840.1A
Authority: EP
Inventors: Markus Brandhorst
Original assignee: Arkema France SA
Current assignee: Arkema France SA
Priority date: 2012-11-09
Filing date: 2013-11-07
Publication date: 2015-09-16
Also published as: CN104797552A; BR112015009442A2; FR2997949A1; US20150299107A1; FR2997950A1; WO2014072641A1

Abstract

The invention concerns a method for the selective extraction of a reaction product, originating from an oxidative cleavage of an unsaturated fatty acid or of an ester derivative or of an unsaturated nitrile derivative, said reaction product being a co-functionalised acid chosen from the C₆to C15 diacids, ester-acids and nitrile-acids, using, as the selective extraction solvent, a composition comprising a mixture of water and C1-C4 carboxylic acid. The invention also concerns the use of said method and the extraction solvent composition for the preparation of C6 to C15 amino acid, diacid or ester-acid monomers for the production of polycondensation polymers, in particular polyamides.

Description

SELECTIVE EXTRACTION OF OMEGA-FUNCTIONALIZED ACID AFTER OXIDIZING CUT OF UNSATURATED FATTY ACID AND DERIVATIVES

The work that led to this invention received funding from the European Union under the 7th Framework Program (FP7 / 2007-2013) under the project number N ° 241718 EUROBIOREF.

The object of the present invention relates to a process for the selective extraction of an omega-functionalized (or indicated ω-functionalised) aliphatic acid C ₆ -C ₅ , carrier in the ω position of an acid function or ester or nitrile respectively as a diacid, acid ester or acid nitrile (or cyano acid) from a reaction mixture obtained in particular after oxidative cleavage of an unsaturated fatty acid or its ester derivative including (natural oil) or its nitrile derivative, of renewable origin of industrial quality, using as a selective extraction solvent a specific mixture based on water and at least one carboxylic acid in CrC ₄ , more particularly in CrC ₃ , in specific proportions of water and acid. Also concerned is the use of said specific mixture as a selective extraction solvent for said co-functionalized acid. More particularly, the invention relates to the use of said extraction process in a process for the preparation of monomers α-ω-diacids, ω-ester acids or co-amino acids suitable in particular for the manufacture of polyamides. Natural oils and derivatives used for oxidative cleavage are of limited purity. More particularly, the purity of said unsaturated fatty acid or its ester or nitrile derivative does not exceed 95%, preferably does not exceed 90% and more preferably ranges from 40 to 90% by weight. The industrial grade oils used are Refined Bleeched Deodorized (RBD) oils-Refined-Bleached-Deodorized. These treatments are intended to remove impurities present at the end of the seed pressure step, see solvent extraction. Some of these impurities are light fatty acids, natural pigments present in seeds, gums, phospholipids, etc.

The use of natural oils as a source of acids, other esters or unsaturated fatty nitriles poses a delicate problem insofar as they consist of a mixture of various saturated and unsaturated acids, possibly polyunsaturated, even functionalized, resulting during an oxidative treatment on fatty acid derivatives, especially when implementing the oxidative cleavage, the formation of a mixture of products:

Desired ω-functionalized acids among diacids, acid esters or co-cyano carboxylic acids, in particular of different chain lengths, while having the same functionalizations according to the position of the (or) double bonds on the fatty chain,

• intermediate products (epoxides, glycols),

but also a significant part of the residual by-products and residual starting materials unreacted or non-reactive which are initially saturated, which requires difficult or expensive separation treatments.

This remains valid whether the fatty acids concerned are hydroxylated or not. The separation of the -co-functionalized acid from the residual starting saturated derivatives, for example the separation of Γω-cyano acid from the saturated nitrile present at the start, is particularly complicated because their separation by distillation is difficult because of the boiling points. relatives. This problem posed by the presence in the starting oil of various unsaturated and saturated fatty acids corresponding leads after oxidative treatment (oxidative cleavage) to a multiplication of by-products / co-products and residual products unreacted to to separate. It is all the more acute as we are led in the future to use more and more plants GMO (genetically modified organisms) to improve productivity.

The problem arises more particularly for reaction byproducts which include residual unreacted starting materials, after an oxidative cleavage reaction and having corresponding molecular weights and / or boiling points, at least as high as corresponding characteristics of the acide-functional acid reaction product to be separated / purified. It is obvious that the problem arises for all the unreacted or non-reactive residual byproducts or products which are heavier and those very close to the said produit-functional acid product, so that separation by distillation remains difficult, on the one hand, high boiling points of the products to be separated, which implies a risk of thermal degradation at high temperature (boiling range) and secondly, because several by-products have boiling points very close and it is therefore difficult to separate them by this route. More particularly, the separation of the products obtained by the oxidative cleavage of a fatty acid or a fatty nitrile is a key step. Note the fatty acids CX: Y, with X corresponding to the chain length and Y corresponding to the number of unsaturations. In addition, the double bond may be in cis or trans conformation. It is possible to add delta-Z or omega-W names, where Z denotes the place of the double bond on the chain by counting from the acid group and W denoting the position from the other end of the chain. The presence of saturated fatty chains (C14: 0, 16: 0, 18: 0 and 20: 0 according to the designation CX: Y) in the raw material leads to the formation of a mixture after cleavage oxidizing which will be difficult to separate by distillation. The boiling points of nitrile-acids and saturated nitriles in the case of cutting nitrile or diacids and saturated acids in the case of acid cutting are very close, although of different chain length. Thus, for example, the 9-carbon diacid has a boiling point close to C 16: 0 palmitic acid and stearic acid. The selective extraction of the acid-nitrile or diacid with respect to saturated fatty nitrile or saturated fatty acid using a carboxylic acid / water mixture was explored.

Therefore, there is a need for a non-thermal separation method, avoiding thermal degradation of the product, which can lead to additional by-products to be separated and guaranteeing the thermal and chemical stability of said co-functional acid product (or ester / corresponding nitrile) to be separated, having a high separation efficiency and final purification and an implementation as simple and practical and without complicated and expensive steps.

GB 1 177154 describes, in Example 15, the use of a mixture of acetic acid / water (88.9 / 1 1, 1) as a hydrogenation solvent for 1 1 -cyano-undecanoic acid for obtaining 12-amino-dodecanoic acid. Likewise, this document describes the use of acetic acid as a suitable solvent for the hydrogenation of this compound. The problem described in this document is related to the hydrogenation of 11-cyano-undecanoic acid and does not concern the selective separation of this acid from a multitude of formed by-products (saturated and unsaturated) following an oxidative cleavage. unsaturated fatty acid nitrile, as is the case in the present invention. In addition, a mixture of acetic acid / water (88.9 / 1 1, 1 by volume) does not allow the separation of the target cyano acid from a saturated nitrile.

Perkins et al. Describe in JACS, 1975, 52,473, page 473 in the last paragraph on page 474 in the first paragraphs, the preparation of methyl 8-cyanooctanoate by oxidative cleavage of the oleonitrile via ozonolysis using as solvent for this ozonolysis , acetic acid in the presence of water (implicit mixture corresponding to 90/10). After elimination, by distillation of acetic acid, the crude mixture obtained is esterified with methanol using, as esterification solvent, dichloromethane, which is removed by distillation, after washing the medium with bicarbonate water. Then, the crude mixture of esters obtained is distilled under vacuum. No disclosure or suggestion of using a specific mixture of acetic acid and water to selectively extract 8-cyanooctanoic acid is described herein.

US 4,165,328 discloses a process for the separation-recovery of 11-cyano-undecanoic acid with a degree of purity of between 75 and 95% by weight from a mixture containing cyclohexanone and ε-caprolactam, this mixture being derived from the pyrolysis between 300 and 1000 ° C of 1,1'-peroxydicyclohexylamine. The mixture is first treated with a mixture of aqueous ammonia solution and a solvent among benzene, xylene or toluene, with passage in the organic phase of cyclohexanone and in the aqueous phase the ammonium salt of the 1-cyano-undecanoic acid. The 11-cyano-undecanoic acid is recovered after acidification of this phase at 40-100 ° C., first in the crude and molten state, and then washed with hot water in order to eliminate ε-caprolactam. This process remains specific to obtaining this acid-nitrile from a specific raw material and specific conditions, which do not apply to the problem posed in the case of the oxidative cleavage of an unsaturated fatty acid or an ester or nitrile derivative of this fatty acid. This process generates as a by-product, 1 mole of salt per mole of cyano acid, salt that is necessary, either to eliminate / reprocess as waste, or to reprocess / recover as usable material. This process therefore requires additional steps of treatment of this by-product and as such, it is therefore neither practical nor flexible.

GB 1049229 describes the preparation of an aliphatic carboxylic acid co-cyano from the ammoniation of the corresponding α-ω-diacid, for example obtaining (according to Example 1) 9-cyano-nonanoic acid from the Dioxide diacid 1, 10-decane dioic treated with urea, with as by-products to separate the corresponding dinitrile and ω-cyanocarboxamide corresponding to the starting diacid. Dissolution in a dilute aqueous solution of ammonia and extraction with a water-immiscible solvent such as ether makes it possible to extract neutral products such as dinitrile and the cyano-carboxamide compound, cyano-carboxylates and dicarboxylates. . Then, the ammonia phase is distilled and extracted with chloroform where 9-cyano-nonanoic acid is found and in the residual ammoniacal phase after distillation is recovered the residual 1,10-decanedioic acid diacid. Again, this process has no relation to an oxidative cleavage reaction and the by-products related to this reaction or to the process of the present invention.

No. 3,994,942 discloses a process for recrystallizing 1,1-cyano-undecanoic acid in a solvent which is a mixture of acetic acid / water or propionic acid / water, but does not teach or describe this solvent as a solvent for selective liquid-liquid extraction.

No. 2,468,436 discloses a process for the preparation of a co-cyano-carboxylic acid such as 8-cyanooctanoic acid prepared by oxidation of oleonitrile with a solution of chromic acid and concentrated sulfuric acid with the reaction mixture. extracted with petroleum ether which separates pelargonic acid as a by-product acid, unreacted nitriles, including saturated nitriles present initially in the used oleonitrile. The insoluble residue in petroleum ether contains 8-cyanooctanoic acid, which can be purified by conversion into a barium salt and dissolved in a barium chloride excess with filtration of the impurities before conversion in acid form with sulfuric acid. Although this process uses the oxidation of oleonitrile, the separation and purification method appears complex and involves several distinct steps using materials that are not practical to use and this process is not related to the process of the process. present invention. This process again involves the formation of a salt as a by-product with the same disadvantages as those cited above for a similar process, ie not practical or flexible.

The article entitled "Ozonolysis of unsaturated fatty acids I. ozonolysis of oleic acid" by Ackman et al in Can. J. Chem, 39 (1961) p. 1956-1962 describes the ozonolysis of pure oleic acid in methanol used as a reactive solvent, with decomposition in formic acid by hydrogen peroxide of the ozonide formed. This leads to dicarboxylic acids obtained by oxidative cleavage as main products and a minimum of secondary acid products. Other ozonolytic solvents for pure oleic acid are also described as acetic acid or acetone, such as the oxidative cleavage of pure azelaic acid in formic acid as a reaction solvent. However, this document of academic interest concerns only the oxidative cleavage of pure unsaturated fatty acids with absence of equivalents of saturated fatty acids and other starting materials (saturated and unsaturated) as is the case in a Unsaturated fatty acid of industrial quality of limited purity, as explained at the beginning. In such a case, the composition of the cleavage reaction products and saturated starting materials is much more complex than that described in the cited document with a proportion of reaction by-products and residual non-reactive products significantly important to make their elimination much more difficult and complex than that described in said document.

The solution proposed by the present invention overcomes the drawbacks of the methods known from the state of the art, with a specific and selective method for extracting said co-functionalized acid from the reaction mixture, in particular resulting from an oxidative cleavage. unsaturated fatty acid or its ester (including oil) or unsaturated fatty acid nitrile, said process being based on the use of a specific extraction solvent composition. The main object of the invention relates firstly to said specific process for extracting a co-functionalized acid from a reaction mixture resulting from an oxidative cleavage, then a process for producing said acid or its derivative (Amino acid case from acid nitrile), comprising the use of said selective separation process and finally the use of the specific composition of the selective extraction solvent in such a process for extracting or manufacturing said acid , in particular for the preparation of α-ω acid functional monomers amino acids, diacids or acidic esters.

Thus, the first object of the invention relates to a process for selective separation of a reaction product from the reaction mixture and with respect to unreacted or unreacted residual reaction by-products and starting materials. where: a) said reaction product is at least one co-functionalized acid, in particular selected from diacids, ester-acids or nitrile-acids and having from 6 to 15 carbon atoms,

b) said product is derived from an oxidative cleavage reaction of at least one unsaturated fatty acid, including hydroxylated acid or its ester derivative, including polyol monoester or multi-ester, including glycerol or its derivative nitrile

c) said process comprises at least one step and, more particularly, several successive steps of selective extraction of said co-functional acid product with a selective extraction solvent, which is a composition comprising a mixture of water and at least one a carboxylic acid having 1 to 4 carbon atoms (or C l -C ₄₎ or mixtures thereof, preferably 1 to 3 carbon atoms or mixtures thereof and, more preferably, said acid is acetic acid or formic acid or their mixture, more particularly the mixture of formic acid and acetic acid and in a water / acid ratio such that at the extraction temperature, the mixture of said reaction mixture with said extraction solvent is biphasic, said product reaction, acide-functional acid being selectively concentrated in the aqueous extraction phase and said unreacted or unreactive residual reaction byproducts and starting materials being centered in the organic phase at each extraction step,

d) said process comprises the treatment of said aqueous extraction phase, possibly accumulated over several extractions with removal by evaporation of said extraction solvent, water and acid and recovery of said product with the dry extract thus obtained (recovery of said product under form of dry extract obtained), optionally, said product can be recovered by counter-extraction liquid- liquid from said aqueous phase with a solvent of said product and immiscible with said aqueous phase.

As suitable solvent for said counterextraction, that is to say against the current, one can choose an organic solvent immiscible with the water / carboxylic acid mixture as described according to the invention and having a particular affinity, that is to say, being a good solvent with respect to said product to be extracted. This optional variant has an energy advantage, that is to say with less energy consumed for this recovery variant, with respect to the removal of water and of said carboxylic acid by evaporation in said aqueous extraction phase. .

The composition of said extraction solvent may vary and be adjusted depending on the temperature of the extraction, for a given mixture of water-carboxylic acid. The composition may also vary according to the carboxylic acid used and also according to the desired yield / selectivity compromise. More particularly, the shorter the carboxylic acid, from C ₄ to C 1, the better the extraction selectivity and the longer it is from C 1 to C ₄ , the more the yield or extraction rate is improved.

In the process according to the invention, said extraction may take place at a temperature ranging from the melting point and up to the boiling point of said water / carboxylic acid mixture, preferably from 15 to 70 ° C. and more preferably from 15 to 70 ° C. 50 ° C. The increase in temperature tends to decrease the selectivity and therefore for a given water-acid ratio, the lower temperature favors the extraction selectivity. At the chosen temperature, the organic phase to be extracted (reaction mixture) remains liquid. Different cascading and continuous extraction stages can be envisaged with extraction solvent mixtures and temperatures that can vary (gradient of extraction solvent composition and / or temperature, from one stage to another with a recycling of the residual streams to other stages adapted to their composition, these gradients being adapted to the starting compositions to be extracted (nature and rate of products to be extracted in these compositions)).

More particularly, the temperature of said extraction step c) and said water / acid ratio are chosen such that, during this extraction step, the mixture of the water / acid composition with the reaction mixture (organic reaction phase ) comprising said product to be separated is biphasic with an aqueous phase (water-acid) selectively containing, for the most part, said product to be separated and a non-aqueous phase containing the remainder of the organic phase.

Thus, the water / carboxylic acid weight ratio in said extraction solvent of said extraction step c) may also vary depending on the extraction temperature. used and acid (nature of the acid), from 32/68 to 95/5 and preferably from 38/62 to 85/15.

Preferably, said extraction according to the process of the invention takes place at room temperature, which means 20 ± 5 ° C.

According to a particular option, said extraction step c) comprises several successive washes-extractions of said non-aqueous (organic) phase by said water / acid composition, with recovery and mixing of all the aqueous phases thus obtained before said treatment d) for recovering said co-functional acid product. The extractions can be carried out with the same proportions by weight between the extraction solvent and the reaction mixture to be extracted, but preferably the ratio by weight between the extraction solvent and the weight of the reaction mixture to be extracted varies within a range of from 0.5 / 1 to 100/1, more preferably from 0.5 / 1 to 50/1. More particularly, this ratio is decreased with the number of successive extractions, in order to improve the extraction selectivity of the targeted product.

More particularly, in the case of selective extraction according to the process of the invention of a co-cyano acid, a reaction mixture resulting from an oxidative cleavage, for example 8-cyanooctanoic acid from the oxidizing cleavage of the oleonitrile comprising other saturated nitriles, the initial ratio between the acid-nitrile to be extracted and the other saturated nitriles can go from about 1 initially to more than 300 after said selective extraction. This clearly demonstrates the advantage of the process of the present invention.

According to a particular preferred case, said selective separation process is an integral part of the process for manufacturing said co-functionalized acid product.

The invention also covers a process for producing a co-functionalized acid, in particular an α-ω diacid, an acid co-ester, an acid ω-nitrite or a derivative of these products. and in particular an ω-amino acid as derivative of an acidic co-nitrile which comprises the use of a selective separation process as defined above according to the invention and which manufacturing method comprises a step prior to this use, an oxidative cleavage reaction of an unsaturated starting material, from which reaction are derived said co-functionalized product and said unreacted or unreactive residual byproducts and starting materials, said product of initially subjected to said oxidative cleavage being chosen from at least one unsaturated fatty acid, preferably having at least 10 carbon atoms and more preferably at least 16 carbon atoms and / or an ester derivative of said acid and / or a nitrile derivative of said acid unsaturated fat of the following formula (I): [R1-CH = CH - [(CH ₂ ) _q -CH = CH] _m - (CH ₂ ) _r ] _p -X (I) where

p: is an integer equal to 1, 2 or 3 and

For p = 1, X is chosen from: -C0 ₂ H (fatty monoacid) or -CN (nitrile) or -CO ₂ R '(monoester) with R' being a C 1 -C alkyl, the alkyl being linear or branched when possible, that is to say from C ₄ ,

For p = 2, X is a diester radical = (CO ₂ ) ₂ -Y, with Y being the residue of a diol or residue of glycerol carrying an OH function,

· For p = 3, X is a triester Ξ (00 ₂ ) ₃ -Ζ, with Z being the remainder (trivalent radical without OH) of glycerol (case of fatty acid oil)

R1: is an H or an alkyl radical of 1 to 1 1 carbon atoms, optionally containing an OH function,

q: is equal to 0 or 1,

m: is equal to 0, 1 or 2,

r: is an integer ranging from 4 to 15,

with the C = C unsaturations of said formula which can be of cis or trans conformation.

More particularly, according to this manufacturing method, said unsaturated starting material of formula (I) is chosen from a fatty acid or a fatty acid ester, preferably from oleic acid, oleic oil or a monoester of the formula. oleic acid and more preferably oleic acid.

According to another variant, said unsaturated starting material (I) is a nitrile, preferably oleonitrile or octadec nitrile 11 -eneoic and octadec-12-eneone nitrile or mixtures thereof, synthesized from 1 ricinoleic acid after hydrogenation followed by dehydration. Said nitrile according to (I) is in particular the product of ammoniation (reaction with ammonia) of the corresponding fatty acid or an ester of said fatty acid and in particular of the corresponding oil. Said oxidative cleavage reaction step is preferably carried out using Oxygen and / or Ozone, and in particular hydrogen peroxide, as oxidation agent with oxygenated water.

According to a more particular and preferred case according to this manufacturing method, said unsaturated starting product (I) is oleonitrile and said oxidative cleavage reaction product is 8-cyanooctanoic acid.

According to another more particular and preferred case according to this manufacturing method, said unsaturated starting material (I) is the nitrile of gondoic acid (eicos-1-eneic acid). or vaccenic acid (octadec-1-enoic acid) and the oxidative cleavage reaction product thus obtained is 10-cyano-decanoic acid.

Said reaction by-products and / or unreacted or unreactive residual starting materials may comprise in particular:

saturated fatty acids, esters or nitriles of the same rank as said unsaturated starting material,

the residual unsaturated starting material of the diol or epoxidized derivatives of said unsaturated starting material, formed by oxidative modification other than oxidative cleavage of the ethylenic unsaturation of said unsaturated starting material,

saturated and / or unsaturated higher fatty acids.

Said method for producing a co-functionalized acid preferably relates to the manufacture of an α-ω diacid, an acid co-ester or a co-amino acid as a derivative of a co-cyano acid, comprising from 6 to 15 carbon atoms, said manufacturing method using a selective separation process, as defined above according to the invention for the selective separation of said α-ω diacid, acidic co-ester and co-ester cyanoacid. Such a more preferred process concerns the preparation of a co-amino acid containing from 6 to 15 carbon atoms obtained from its precursor co-cyanoacid (or acid nitrile), said precursor being obtained by a process such that defined according to the invention above, in particular by the oxidative cleavage of a nitrile derivative of an unsaturated fatty acid, preferably comprising at least 10 carbon atoms and more preferably at least 16 carbon atoms, as defined herein. and according to the formula (I) cited above, with said manufacturing process comprising an additional step of hydrogenation of said precursor-cyano-acid to obtain said amino acid. More preferably, said co-cyano acid is 8-cyanooctanoic acid and said co-amino acid derivative is 9-amino-nonanoic acid or said cyano acid is 10-cyano-decanoic acid and said amino acid derivative is 11-amino-undecanoic acid or said cyano acid is 11-cyano-undecanoic acid and said amino acid is 12-amino dodecanoic acid or said cyano acid is 12-cyano acid -dodecanoic acid and said amino acid is 13-amino tridecanoic acid. More particularly, the 10-cyano-decanoic and 11-undecanoic acids can be obtained in a C 11 C 12 mixture after the oxidative cleavage of the 12-hydroxy stearic hydroxylated fatty acid or 12HSA (obtained by hydrogenation of ricinoleic acid) subjected to (12HSA) to dehydration with formation of Cn (between Cn and Ci ₂ ) or Ci ₂ (between C12 and Ci ₃ ) unsaturation.

The present invention also covers the use of a composition comprising a water / carboxylic acid mixture chosen from at least one organic acid having from 1 to ₄ carbon _atoms. or mixtures thereof, preferably formic acid and / or acetic acid and / or propionic acid or mixtures thereof, and more preferably formic or acetic or propionic acid or mixtures thereof, more preferably acetic acid or formic acid or mixtures thereof, in particular the formic acid and acetic acid mixture, as a selective extraction and separation-purification solvent of at least one reaction product chosen from an α-ω diacid, a ω-ester-acid, co-cyanoacid (or nitrile-acid), having from 6 to 15 carbon atoms, from a reaction mixture comprising reaction by-products and / or unreacted residual or unreactive residual products heavier reaction mixture resulting from an oxidative cleavage reaction of an ethylenically unsaturated starting material selected from at least one unsaturated fatty acid including hydroxyl or an ester derivative including a monoester or a multi-ester of a polyol glycerol or a nitrile derivative of said unsaturated fatty acid, preferably having at least 10 carbon atoms and more preferably at least 16 carbon atoms, the water / carboxylic acid ratio in said extraction solvent being adjusted in such a way, at the extraction temperature, that the mixture of said solvent with said reaction mixture is biphasic at said temperature. More particularly, in this use, the water / carboxylic acid ratio can vary, depending on the extraction temperature and the carboxylic acid used, from 32/68 to 95/5 and preferably from 38/62 to 85 / 15. This use is of particular interest when said reaction product is 8-cyanooctanoic acid obtained from the oxidative cleavage of the oleonitrile or when said reaction product is azelaic acid (nonanedioic acid) obtained at from the oxidative cleavage of oleic acid or said product is the monoester of azelaic acid and obtained from an oleic acid ester or when said product is 10-cyano-decanoic acid and obtained from the oxidative cleavage of the nitrile of the gondoic acid and / or from the nitrile of the vaccenic acid.

Finally, the use of a selective extraction or separation process as defined according to the invention described above for the preparation of co-amino acid monomers, α-ω diacids or co-ester-acids as monomers For the manufacture of polycondensation (or poly) polymers, such as polyamides or polyesters, particularly polyamides, is also part of the present invention. This process is of particular interest in the preparation of diacid or amino acid monomers for polyamides and more particularly in the preparation of 9-amino-nonanoic acid for the preparation of polyamide PA 9 or in the preparation of the acid 1 amino-undecanoic acid for the preparation of polyamide PA 11 or in the preparation of 12-amino-dodecanoic acid for the preparation of polyamide PA 12 or in the Thus, the present invention also relates to the use of the process as defined above according to the invention in the preparation of the 9-amino-acid. nonanoic acid for the preparation of polyamide PA 9 or in the preparation of 11-amino-undecanoic acid for the preparation of polyamide PA 11 or of amino 12 dodecanoic acid for the preparation of polyamide PA 12 or of acid 13-amino tridecanoic acid for the preparation of polyamide PA 13. Therefore, said selective separation process according to the invention can be part of a process for the preparation of amino acid monomers in a process for the preparation of polyamides, in particular PA 9, PA 1 1, PA 12 and PA 13. 13-Amino tridecanoic acid can be obtained from 12-cyano-dodecanoic acid, the latter as a product of the oxidative cleavage of the erucic nitrile (13-eneic doeicos) and selective extraction according to the method of the present invention.

The following examples are given by way of illustration of the invention and its performance and in no way limit the scope of the claims.

Examples

Raw materials used (see Tables 1a and 1b below)

Table 1a: Carboxylic Acids in Extraction Solvent

The water used in the mixture for the extraction solvent is demineralised water. Table 1b: reaction mixtures to extract

EXAMPLE 1 Extraction of 8-cyanooctanoic acid from an R1 reaction mixture resulting from the oxidative cleavage of oleonitrile

The reaction mixture R1 used is a solution having a composition as shown in Table 2 below (according to analysis by gas chromatography).

Table 2: Composition of the R1 reaction mixture

This mixture is obtained from the oxidative cleavage of an oleonitrile (purity of

80%, of Arkema origin). The cleavage was carried out in a batch reactor at 80 ° C. for 24 h using tungstic acid as catalyst and an aqueous solution of water oxygenated (70% by weight of H ₂ O ₂ ) to 63% by weight of pure H ₂ 0 ₂ relative to the (pure) oleonitrile. A flow of air passed through the reaction mixture.

The starting mole ratio of 8-cyanooctanoic acid (A8CO) onΣ (sum) saturated nitriles (myristic nitrile + palmitic nitrile + stearic nitrile + arachidic nitrile) is (A8CO) / Σ saturated nitriles = 3,4 . The reaction mixture used corresponds to that obtained after washing with water.

Extraction procedure

For extraction, about 2 g of R1 solution was contacted in a separatory funnel with about 20 g of a solution of a preformed mixture of carboxylic acid / water at the indicated temperature. Both solutions were mixed vigorously for about 1-2 minutes. After more than 30 minutes, the aqueous phase was separated, the carboxylic acid and water evaporated under vacuum <1 mbar, 40 ° C and the remaining product was analyzed by gas chromatography. For the two carboxylic acid tests, the acids were premixed (50/50 weight ratio) and then mixed with water to form the extraction solvent composition.

Determination of the concentration of carboxylic acid to be mixed with the water

The solution of the oxidative cleavage is soluble in the carboxylic acid. To determine the amount of water needed to obtain two distinct phases, water was added as it went. After stirring in a separatory funnel, the ampoule was allowed to stand for at least 5 minutes. The presence of a meniscus after 5 minutes was used to determine the minimum water / carboxylic acid ratio as shown in Table 3 below.

Table 3: Determination of the acid / water ratio

Carboxylic acid Quantity Amount of water Temperature Formation of an acid (% wt) (° C) meniscus carboxylic acid

(%weight)

Formic acid (AF) 53 47 20 No

Formic acid (AF) 49 51 20 Yes

Acetic acid (AA) 64 36 20 No

Acetic acid (AA) 61 39 20 Yes

Acetic acid (AA) 68 32 60 No Acetic acid (AA) 66 34 60 Yes

Propionic Acid (PA) 55 45 20 No

Propionic acid (PA) 53 47 20 Yes

Acetic acid mixture / 71 29 20 Non formic acid 50/50

weight (AA / AF 50/50)

Acetic acid mixture / 68 32 20 Yes formic acid 50/50 in

weight (AA / AF 50/50)

Extraction selectivity (see Table 4 below)

Table 4: A8CO / saturated nitrile molar ratio and other characteristics of yield and selectivity according to some extraction parameters

Sol de = Starting solution before extraction (reaction mixture before extraction) A8CO = 8-cyanooctanoic acid

ΣNitrile _its t = sum of saturated nitriles = nitrile myristic palmitic nitrile + + + nitrile nitrile stearic arachidic ^* Total amount of extract by the acid / water phase measured after evaporation of carboxylic acid / water, the "dry extract" being the dry matter in the sense that there is no solvent.

Table 4 shows that 8-cyanooctanoic acid (A8CO) is preferentially extracted from saturated nitriles. The molar ratio A8CO / t increases _its nitrile in the aqueous phase extracted with said water-acid mixture. The selectivity decreases with the chain length of the carboxylic acid. The selectivity decreases as the extraction temperature increases.

The amount extracted (overall) increases with the chain length of the carboxylic acid. Adding water to the carboxylic acid reduces the amount extracted, that is, increasing the water / acid ratio decreases this amount or extraction yield.

EXAMPLE 2 Extraction of a Diacid (Azelaic Acid: AZ) from a Reaction Mixture R2 from the Oxidic Breakdown of Oleic Acid

The oxidative cleavage reaction of oleic acid is carried out in a manner similar to that for the oxidative cleavage of oleonitrile (substitution with oleic acid).

The oleic acid used is Oleon at 75% purity. The reaction takes place at 70 ° C without air flow and with 144% pure H ₂ 0 ₂ relative to pure oleic acid.

A sample of reaction mixture R2 from the oxidative cleavage of oleic acid was extracted with a solvent mixture: acetic acid (AA) / water corresponding to AA / water = 58/42 by weight.

A weight of 2.1 g of solution (R2) resulting from said oxidative cleavage was contacted with a weight of 24.9 g of said solvent mixture AA / water. Thus, 36.9% of the azelaic acid initially present was extracted with this solvent mixture. The composition of the extract is given in Table 5 below. The weight ratio of azelaic acid to fatty acid (14: 0, 16: 0, 18: 0) before extraction is 2.3 and increases to 28.8 after extraction.

Table 5 below gives the composition of the oleic acid cleavage solution and its extract with acetic acid (AA) / water 58/42 (weight ratio). Table 5: Composition before extraction in reaction mixture R2 and

after extraction in the dry extract

Component Before extraction Dry extract (material 100% without

(% weight) solvent) (% weight)

Hexanoic acid (A6) 0.7 0.7

Nonanal 1, 1 0.2 A7 2.3 2.3

A8 1.2 1.3

A9 17.5 17.6

A10 0.3 0.2

Suicide acid 0.3 0.7

Azelaic acid 16.0 31.3

C14: 0 1.9 0.5

Sebacic acid 0.4 0.7

Undecanoic acid 2.1 3.7 (AU)

C16: 0 3.8 0.6

Dodecanoic acid 0.3 0.5

C18: 0 1.2 0.0

Claims

1. Process for the selective separation of a reaction product from the reaction mixture and with respect to unreacted or unreacted residual reaction products and by-products, characterized in that:

a) said reaction product is at least one ω-functionalized acid, in particular selected from diacids, ester-acids or nitrile-acids and comprises from 6 to 15 carbon atoms,

b) said product is derived from an oxidative cleavage reaction of at least one unsaturated fatty acid, including hydroxylated acid or its ester derivative, including polyol monoester or multi-ester, including glycerol or its nitrile derivative; ,

c) said method comprises at least one step and more particularly several successive steps of selective extraction of said co-functional acid product, with a selective extraction solvent, which is a composition comprising a mixture of water and at least one carboxylic acid having 1 to 4 carbon atoms or mixtures thereof, preferably 1 to 3 carbon atoms or mixtures thereof, more preferably, said acid being acetic acid or formic acid or mixtures thereof, more particularly the mixture of formic acid and acetic acid and in a water / acid ratio such that at the extraction temperature, the mixture of said reaction mixture with said extraction solvent is biphasic, said produit-functional acid reaction product being selectively concentrated in the aqueous extraction phase and said unreacted or unreactive residual reaction byproducts and starting products being concentrated in the phas e organic, at each stage of extraction

d) said process comprises the treatment of said aqueous extraction phase, possibly cumulative over several extractions, with elimination by evaporation of said extraction solvent, water / acid and recovery of said product with the dry extract thus obtained, optionally said product which can be recovered by liquid-liquid counter-extraction of said aqueous phase with a solvent of said product and immiscible with said aqueous phase.

2. Method according to claim 1, characterized in that in said extraction solvent of said extraction step c), said water / carboxylic acid weight ratio varies also as a function of the extraction temperature of 32/68. at 95/5 and preferably from 38/62 to 85/15.

3. Method according to claim 1 or 2, characterized in that said extraction takes place at a temperature ranging from the melting point to the boiling point of said water / carboxylic acid mixture, preferably from 15 to 70 ° C and more preferably from 15 to 50 ° C.

4. Method according to one of claims 1 to 3, characterized in that said extraction takes place at room temperature (20 ± 5 ° C).

5. Method according to claim 1 or 2, characterized in that the temperature of said extraction step c) and said water / acid ratio are chosen such that, during this extraction step, the mixture of the composition water / acid and the reaction mixture (organic reaction phase) comprising said product to be separated is biphasic with an aqueous phase (water-acid) selectively containing, for the most part, said product to be separated and a non-aqueous phase containing the remainder of the organic phase.

6. Method according to one of claims 1 to 5, characterized in that said extraction step c) comprises several successive wash-extractions of said non-aqueous phase (organic) with said water / acid composition with recovery and mixing of all the aqueous phases thus obtained before said treatment d) to recover said co-functional acid product, preferably with a ratio by weight of the water / acid composition to the weight of the organic phase to be extracted ranging from 0.5 to 100/1 preferably from 0.5 / 1 to 50/1 and more particularly this ratio being decreased with the number of successive extractions.

7. Method according to one of claims 1 to 6, characterized in that it is an integral part of the manufacturing process of said co-functionalized acid product.

8. Process according to one of claims 1 to 7, characterized in that the purity of said unsaturated fatty acid or its ester or nitrile derivative does not exceed 95%, preferably does not exceed 90% and more preferably varies from 40 to 90% by weight.

9. A process for producing a co-functionalized acid, in particular an α-ω diacid, an acid ω-ester or an acidic co-nitrile or a derivative of these products, and in particular a co-amino acid as a derivative of an acidic co-nitrile, characterized in that it comprises the use of a selective separation process, as defined in claim 6, which manufacturing method comprises a step prior to this use, an oxidative cleavage reaction of an unsaturated starting material, from which reaction are derived said co-functionalized product and said unreacted or unreactive residual byproducts and starting materials, said starting material subjected to said oxidative cleavage being chosen from at least one unsaturated fatty acid, preferably having at least 10 carbon atoms. carbon and more preferably having at least 16 carbon atoms and / or an ester derivative of said acid and / or a nitrile derivative of said unsaturated fatty acid of following formula (I):

[R 1 -CH = CH - [(CH ₂ ) q -CH = CH] _m - (CH ₂ ) _r ] _p -X

or

p: is an integer equal to 1, 2 or 3 and

for p = 1, X is chosen from: -C0 ₂ H (fatty monoacid) or -CN (nitrile) or -CO ₂ R '(monoester) with R' being a C 1 -C alkyl,

for p = 2, X is a diester radical = (CO ₂ ) ₂ -Y, with Y being the residue of a diol or glycerol carrying an OH function,

for p = 3, X is a triester Ξ (00 ₂ ) ₃ -Ζ, with Z being the residue (trivalent radical without OH) of glycerol (case of fatty acid oil),

q: is equal to 0 or 1,

m: is equal to 0, 1 or 2,

r: is an integer ranging from 4 to 15,

10. Process according to claim 9, characterized in that said unsaturated starting material is chosen from a fatty acid or a fatty acid ester, preferably from: oleic acid, oleic oil or a monoester of the oleic acid, more preferably oleic acid.

1 1. Process according to claim 9, characterized in that said unsaturated starting material is a nitrile, preferably oleonitrile or nitrile octadec-1-ene-oic and nitrile octadec 12-ene-oic or mixtures thereof synthesized from ricinoleic acid after hydrogenation followed by dehydration.

12. The method of claim 1 1, characterized in that said nitrile is the ammoniation product (reaction with ammonia) of the corresponding fatty acid or an ester of said fatty acid and in particular of its oil.

13. Method according to one of claims 9 to 12, characterized in that said oxidative cleavage reaction step is carried out using oxygenating water, oxygen and / or ozone as oxidation agent, preferably hydrogen peroxide.

The process according to claim 11, wherein said unsaturated starting material is oleonitrile and said reaction product is 8-cyanooctanoic acid.

15. The process as claimed in claim 11, wherein said starting material is the nitrile of gondoic acid (eicos-1-eneic acid) or the nitrile of the vaccenic acid (octaded-1-ene acid). oïque) and that the reaction product obtained is 10-cyano-decanoic acid.

16. Process according to one of Claims 1 to 15, characterized in that the said reaction by-products and / or unreacted residual or unreactive residual starting materials comprise:

the residual unsaturated starting material of the diol or epoxidized derivatives of said unsaturated starting product, formed by oxidative modification other than oxidative cleavage of the ethylenic unsaturation of said unsaturated starting material,

higher saturated and / or unsaturated fatty acids.

17. Process according to one of Claims 9 to 16, characterized in that it concerns the preparation of a co-amino acid containing from 6 to 15 carbon atoms, characterized in that it is obtained from its precursor co-cyano-acid, said precursor being obtained by a process as defined according to one of claims 1 to 8 and 10 to 15 and said manufacturing process comprising an additional step of hydrogenation of said precursor co-cyano-acid to obtain said amino acid.

18. Process according to claim 17, characterized in that said co-cyano acid is 8-cyanooctanoic acid and said co-amino acid derivative is 9-amino-nonanoic acid or that said cyanoacid is 10-cyano-decanoic acid and said amino acid derivative is 11-amino-undecanoic acid.

19. Use of a composition comprising a water / carboxylic acid mixture chosen from at least one C ₁ -C ₄ organic acid or mixtures thereof, preferably formic acid and / or acetic acid and / or propionic acid, or mixtures thereof, and more preferably acetic acid or formic or propionic acid or mixtures thereof, still more preferably acetic acid or formic acid or mixtures thereof, in particular the formic acid and acetic acid mixture, as a selective extraction solvent and separation-purification, of at least one reaction product chosen from an α-ω diacid, a co-ester-acid or a co-cyano acid, comprising from 6 to 15 carbon atoms, from a reaction mixture comprising reaction by-products and / or heavier unreacted or unreacted residual starting materials, reaction mixture resulting from an oxidative cleavage reaction of an ethylenically unsaturated starting material selected from i at least one unsaturated fatty acid including hydroxyl or ester derivative including monoester or multi-ester of a polyol including glycerol or a nitrile derivative of said unsaturated fatty acid, preferably having at least 16 carbon atoms, the water / carboxylic acid ratio in said extraction solvent being adjusted in such a way, at the extraction temperature, that the mixture of said solvent with said reaction mixture is biphasic at said temperature.

20. Use according to claim 19, characterized in that said water / carboxylic acid ratio varies, depending on the extraction temperature and the carboxylic acid used, from 32/68 to 95/5 and preferably from 38 62 to 85/15.

21. Use according to claim 19 or 20, characterized in that said reaction product is 8-cyanooctanoic acid obtained from the oxidative cleavage of the oleonitrile or in that said reaction product is azelaic acid (acid nonanediodioic acid) obtained from the oxidative cleavage of oleic acid or the monoester of azelaic acid obtained from an oleic acid ester or in that said product is 10-cyano decanoic acid obtained from the oxidative cleavage of the nitrile of gondoic acid and / or the nitrile of the vaccenic acid

22. Use of the process as defined according to one of claims 1 to 8, in the preparation of 9-amino-nonanoic acid for the preparation of polyamide PA 9 or in the preparation of 1-amino-amino acid. undecanoic acid for the preparation of polyamide PA 11 or in the preparation of 12-amino-dodecanoic acid for the preparation of polyamide PA 12 or in the preparation of 13-amino tridecanoic acid for the preparation of PA 13 polyamide.