Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C67/00—Preparation of carboxylic acid esters
  • C07C67/08—Preparation of carboxylic acid esters by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
  • B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
  • B01J31/0215—Sulfur-containing compounds
  • B01J31/0225—Sulfur-containing compounds comprising sulfonic acid groups or the corresponding salts
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C67/00—Preparation of carboxylic acid esters
  • C07C67/03—Preparation of carboxylic acid esters by reacting an ester group with a hydroxy group
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C69/00—Esters of carboxylic acids; Esters of carbonic or haloformic acids
  • C07C69/52—Esters of acyclic unsaturated carboxylic acids having the esterified carboxyl group bound to an acyclic carbon atom
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11C—FATTY ACIDS FROM FATS, OILS OR WAXES; CANDLES; FATS, OILS OR FATTY ACIDS BY CHEMICAL MODIFICATION OF FATS, OILS, OR FATTY ACIDS OBTAINED THEREFROM
  • C11C3/00—Fats, oils, or fatty acids by chemical modification of fats, oils, or fatty acids obtained therefrom
  • C11C3/003—Fats, oils, or fatty acids by chemical modification of fats, oils, or fatty acids obtained therefrom by esterification of fatty acids with alcohols
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2231/00—Catalytic reactions performed with catalysts classified in B01J31/00
  • B01J2231/40—Substitution reactions at carbon centres, e.g. C-C or C-X, i.e. carbon-hetero atom, cross-coupling, C-H activation or ring-opening reactions
  • B01J2231/49—Esterification or transesterification
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E50/00—Technologies for the production of fuel of non-fossil origin
  • Y02E50/10—Biofuels, e.g. bio-diesel

Definitions

• the invention relates to the treatment of fatty acids, and more particularly the esterification of fatty acids.
• the fatty acid esters obtained can thus serve as raw materials in various fields such as cosmetics or biofuel production.
• the invention relates to an acid composition which can in particular be used as a catalyst in the processes for the esterification of fatty acids.
• the application WO2007005003 provides a process for producing alkyl esters of fatty acids from "tall oil” containing sulfur compounds in the presence of a strong acid catalyst such as in particular para-toluene acid sulfonic acid.
• US Pat. No. 4,652,406 describes the use of aromatic sulphonic acids as a catalyst for esterifying free fatty acids in oils.
• para-toluenesulfonic acid being less soluble in aqueous medium, phase separation is made more difficult.
• alkanesulphonic acids being relatively expensive compounds, it is sought to optimize their use. In addition, it may be useful to further improve the efficiency of the esterification catalysts.
• an object of the present invention is therefore to find an acid catalyst which is more effective, both in terms of fatty acid conversion and in terms of the kinetics of esterification, and is inexpensive.
• a catalyst comprising at least one particular acid composition makes it possible, among other things, to overcome these disadvantages.
• the present invention relates to a composition comprising:
• the proportion by weight of alkanesulphonic acid relative to the total weight of alkanesulphonic acid and arylsulphonic acid is between 5% and 85%, preferably between 8% and 65%;
• the proportion by weight of arylsulphonic acid relative to the total weight of alkanesulphonic acid and arylsulphonic acid is between 15% and 95%, preferably between 35% and 92%.
• the solvent may be of any type known to those skilled in the art and for example water, an organic solvent for a mixture of organic solvents or a mixture of water and one or more organic solvents.
• the solvent is chosen from water, an alcohol and an ether, preferably water and a C 1 to C 3 alcohol, and more particularly, water and water. methanol, alone or in combination.
• the proportion by weight of solvent relative to the total weight of the composition is generally between 0% and 50%, preferably between 5% and 35%.
• halogen atom is preferably selected from fluorine, chlorine and bromine, preferably fluorine.
• the alkanesulfonic acid, of formula R-SO3H defined above, usable in the context of the present invention is advantageously selected from methanesulfonic acid, ethanesulfonic acid, n-propane acid. sulfonic acid, / 'n-propane-sulfonic acid, n-butane-sulfonic acid, the acid / sulfonic n-butane, sec-butane-sulphonic acid, tert-butane acid sulfonic acid trifluoro methanesulfonic acid (also known as triflic acid), and mixtures of two or more of them in all proportions, and most preferably, methanesulfonic acid.
• the aryl-sulphonic acid is chosen from benzene sulphonic acid, para-toluene sulphonic acid, naphthalene sulphonic acid, phenanthrene sulphonic acid, anthracene sulphonic acid, xylene sulphonic acid, alkyl benzene sulphonic acid, cumene sulphonic acid, and very particularly preferably para-toluene sulphonic acid.
• the acidic composition according to the present invention may comprise one or more additive (s) and / or filler (s), which are well known to those skilled in the art, such as those chosen for example from corrosion inhibitors. perfumes, odorous agents, and others.
• additives such as those chosen for example from corrosion inhibitors. perfumes, odorous agents, and others.
• the present invention also relates to the use of said composition as an esterification catalyst, and more particularly esterification of fatty acid (s).
• the invention relates to a method for producing fatty acid esters comprising the steps of:
• step d can be performed simultaneously with step a and / or b, preferably at the same time as steps a and b.
• Step e / may be carried out by heating with or without vacuum, or by decantation of the water / alcohol phase with respect to the fatty acid ester phase.
• the molar ratio catalyst / fatty acids may be between 0.001 and 0.5 and more particularly between 0.01 to 0.2.
• Figure 1 represents the percentage of residual fatty acids (y-axis) in the organic phase after esterification reaction depending on the nature of the acid catalyst used.
• Figure 2 shows the kinetics of conversion of residual fatty acids during the esterification step depending on the nature of the acid catalyst used.
• AMS 100 means that the catalyst used contains 70% pure methanesulfonic acid and 30% water.
• 70 AMS / 30 APTS means that the catalyst used is the catalyst according to the invention and that it comprises:
• - 100 APTS means that the catalyst used comprises 89% pure para-toluenesulfonic acid and 1 1% water.
• the AMS used is an AMS diluted to 70% by weight in water and the para-toluene sulfonic acid used is an acid diluted to 89% by weight in water.
• composition comprising:
• At least one aryl sulfonic acid At least one aryl sulfonic acid.
• aryl is meant all aromatic radicals, such as, for example, phenyl, naphthyl, phenanthryl and anthryl radicals, preferably those comprising from 1 to 3 rings; said radicals being capable of being substituted by at least one alkyl having from 1 to 6 carbon atoms, preferably from 1 to 4 atoms carbon, such as, for example, methyl, ethyl, propyl, butyl, preferably methyl.
• the aromatic radical is a radical substituted by at least one alkyl, it may be, for example, tolyl, xylyl, ethylphenyl or cumenyl. These acids can be used alone or as a mixture.
• the proportion by weight of pure alkanesulphonic acid relative to the total weight of alkanesulphonic acid and arylsulphonic acid is between 5% and 85%;
• the proportion by weight of pure arylsulphonic acid relative to the total weight of alkanesulphonic acid and arylsulphonic acid is between 15% and 95%.
• the proportion by weight of pure alkanesulphonic acid relative to the total weight of alkanesulphonic acid and arylsulphonic acid is between 8% and 65%;
• the proportion by weight of pure arylsulphonic acid relative to the total weight of alkanesulphonic acid and of arylsulphonic acid is between 35% and 92%.
• pure is meant a compound undiluted in water or a solvent.
• composition may also comprise one or more solvents, and optionally one or more additives.
• solvent aqueous products, organic or water-soluble.
• the solvent may be water, an alcohol or an ether, taken alone or in combination.
• the solvent is water and / or a C1 to C3 alcohol.
• the solvent is water, methanol or a water / methanol mixture.
• the content by weight of solvent relative to the total weight of the composition is between 0 and 50%, and preferably between 5 and 35%.
• the alkane sulphonic acid included in the composition according to the invention is chosen from methanesulfonic acid, ethanesulfonic acid, n-propanesulfonic acid, acid and / or n-propane-sulfonic acid, n-butane sulfonic acid, / 'n-butane-sulfonic acid, sec-butane-sulphonic acid, tert-butane-sulphonic acid and trifluoro methanesulfonic acid sulfonic acid (also known as triflic acid), and mixtures of two or more of them in all proportions.
• the alkanesulfonic acid is methanesulfonic acid.
• Said alkane-sulfonic may be used as such, or in combination with one or more other components, that is to say in formulation.
• Any type of formulation comprising at least one alkanesulphonic acid may be suitable.
• the formulation comprises from 0.01% to 100% by weight of alkanesulfonic acid, more generally from 0.05% to 90% by weight, in particular from 0.5% to 75% by weight, inclusive, of acid (s) alkanesulphonic acid (s), based on the total weight of said alkanesulfonic acid formulation.
• the formulation is for example an aqueous, organic, or alternatively hydro-organic formulation.
• the formulation may be prepared as a concentrated mixture, wherein the concentrated mixture may be diluted prior to use.
• the formulation may be a pure alkanesulphonic acid, or a mixture of pure alkanesulphonic acids, that is to say that the formulation may contain only one or more acids. (s) alkane sulfonic acid (s), without any other formulation additive or other solvent or diluent.
• the alkanesulfonic acid may be diluted to 70% in a solvent, preferably in water.
• the alkanesulfonic acid is methanesulfonic acid diluted to 70%, such as that found commercially. It is possible, for example, to use anhydrous methanesulfonic acid or AMSA (acronym for "anhydrous methane sulphonic acid" in the English language) or even methanesulfonic acid in aqueous solution, for example a methanesulfonic acid solution.
• AMSA anhydrous methanesulfonic acid or AMSA (acronym for "anhydrous methane sulphonic acid" in the English language) or even methanesulfonic acid in aqueous solution, for example a methanesulfonic acid solution.
• AMS LC methanesulfonic acid
• Use may also be of methanesulfonic acid in aqueous solution, such as sold by BASF under the name Lutropur ® MSA, ready for use or diluted in water for example, in the proportions indicated below above.
• the aryl-sulphonic acid is chosen from benzene sulphonic acid, para-toluene sulphonic acid, naphthalene sulphonic acid, phenanthrene sulphonic acid, anthracene sulphonic acid, xylene sulphonic acid and cumene sulphonic acid, and very particularly preferably para-toluene sulphonic acid.
• the aryl sulfonic acid included in the composition may be used alone or in combination with one or more other components, that is to say in formulation.
• any type of formulation comprising at least one aryl sulfonic acid may be suitable.
• the formulation comprises from 0.01% to 100% by weight of arylsulphonic acid, more generally from 0.05% to 95% by weight, in particular from 74% to 89% by weight, limits included. of aryl-sulfonic acid relative to the total weight of said formulation.
• the formulation is for example an aqueous, organic, or alternatively hydro-organic formulation.
• the formulation can be a concentrated mixture.
• the formulation may also be a ready-to-use formulation, i.e., it does not need to be diluted.
• the formulation may be pure aryl sulfonic acid without other formulation additive or other solvent or diluent.
• the aryl-sulphonic acid is para-toluenesulphonic acid diluted or not, between 60 and 100% by weight in water, such as that marketed by the Huntsman company for example.
• para-toluene sulfonic acid is diluted to 89% by weight in water such as that marketed by Sigma-Aldrich.
• the composition according to the invention is used as an acid esterification catalyst, and preferably an acidic esterification catalyst of fatty acids.
• the present invention also relates to an acidic esterification catalyst, preferably fatty acid esterification comprising, and preferably consisting of, the acid composition as defined above.
• the composition according to the invention finds a particularly advantageous use as a catalyst, for example as a catalyst for esterification of pure fatty acids or in a mixture in oils or fats, which are then called "fatty acids free ", as opposed to the fatty acids present in the form of mono-, di- and / or tri-glycerides present in said oils and / or fats.
• the esterification reaction of the fatty acids makes it possible, from the condensation of an alcohol with a fatty carboxylic acid, to obtain an ester and a molecule of water.
• fatty acid means a carboxylic acid with an aliphatic chain, in particular a C 4 -C 36 chain.
• the natural fatty acids have a carbon chain, saturated or unsaturated, linear or branched, comprising from 4 to 36 carbon atom (s).
• the fatty acids may, preferably, be fatty acids present in the oils.
• the esterification reaction may be followed by a transesterification reaction in the presence of a light alcohol (1 to 4 carbon atoms) to obtain fatty acid esters and glycerol, said esters of fatty acids can then be used as fuel ("biodiesel").
• the Applicant has thus demonstrated that, with respect to an alkanesulfonic acid used alone as catalyst or with respect to an aryl-sulphonic acid used alone as a catalyst, the mixture of at least one alkane-sulphonic acid with an acid aryl-sulfonic in the proportions claimed, allows, after an esterification step, to lower the level of residual fatty acids in organic phase below 1.1% by weight, preferably 1% by weight , and more particularly 0.95%; which is very difficult to achieve with an alkanesulfonic acid used alone or an arylsulfonic acid used alone.
• This low content of residual fatty acids has in particular an advantage over the final purity of the ester or during the transesterification step, often performed later, since the latter will consume less catalyst, usually basic catalyst, often expensive, and limit the formation of soaps that disrupt the reaction.
• the use of the acid composition according to the invention as an esterification catalyst makes it possible to obtain a smaller amount of residual catalyst in the organic phase than that obtained with the alkane-acid catalyst. sulfonic alone. This makes it possible to reduce the consumption of basic catalyst during a possible subsequent transesterification step in order to prepare, for example biodiesel.
• composition according to the invention makes it possible to improve the conversion kinetics of the fatty acids with respect to the use of an alkane-sulphonic acid used alone. or an aryl sulfonic acid used alone.
• the composition according to the invention is an esterification and transesterification catalyst thus making it possible to carry out, in a single step, the esterification and transesterification of free fatty acids and of fatty acids present in the form of mono-, di- and / or tri-glycerides.
• composition according to the invention may comprise one or more additives well known to those skilled in the art, such as those chosen from corrosion inhibitors, perfumes, odorants, and other additives well known to the art. skilled person.
• the composition according to the invention comprises at least one corrosion inhibitor.
• the composition comprises at least one perfume and / or an odorant.
• composition according to the invention may be prepared according to any method known to those skilled in the art such as, for example, the process described below, said method not being limiting.
• the alkanesulfonic acid In a container is introduced at room temperature, the alkanesulfonic acid. The aryl sulfonic acid is then added in solid form, and the mixture is heated to 40 ° C until completely dissolved. In case a solvent and any additives are used, it is preferable to pre-mix with the alkanesulfonic acid before slowly adding aryl-sulfonic acid.
• the present application also relates to a process for the production of fatty acid esters in which the fatty acids are esterified in the presence of the composition according to the invention.
• the esterification process consists in introducing a fatty acid or a mixture of fatty acids into a reactor.
• the alcohol is then added and the medium is heated to a temperature generally between 50 ° C and 200 ° C, more generally between 60 ° C and 120 ° C, preferably between 60 ° C and 80 ° C.
• the introduction of the composition according to the invention is preferably carried out at the esterification temperature.
• said composition may be added before heating.
• the alcohol and said composition may be added continuously, together or separately, when the medium has reached the esterification temperature.
• said composition may be added with the fatty acid or the mixture of fatty acids.
• the fatty acid or the mixture of fatty acids, the alcohol and said composition are added together before heating.
• the esterification reaction is then carried out in the temperature range indicated above.
• composition according to the invention acts as a catalyst.
• the fatty acids may be of any type selected from fatty acids and mixtures of fatty acids known to those skilled in the art, including fatty acids from the plant or animal medium, including algae, and more generally of the vegetable kingdom. These said acids generally and advantageously comprise at least one olefinic unsaturation.
• acids are most often present in vegetable oils extracted from various oleaginous plants such as, in a non-limiting manner, peanuts, sunflower, rapeseed, castor oil, lesquerella, olive, soya, oil palm, avocado, walnut, hazelnut, almond, sesame, sea buckthorn and limanthus, including algae. They can also come from the terrestrial animal world or marine, and in the latter case, they may be derived from fish fats or fats of mammals, such as, for example and without limitation, fats from cattle, cod, whales or seals. Finally, said acids can come from recycled used oils such as, in a non-limiting manner, cooking oils ("used cooking oil" in English).
• the acids present in these oils are placed in the presence of an alcohol.
• the alcohol may be of any type known to those skilled in the art such as mono-alcohols, diols, triols, tetrols, and the like, used alone or in combination.
• the alcohol used has a molar mass of between 30 g. mol "1 and 200 g.mol " 1 .
• the alcohol is of the type R 1 -OH where R 1 is a linear or branched, saturated or unsaturated alkyl or aromatic chain comprising from 1 to 20 carbon atoms.
• R 1 is an alkyl chain containing from 1 to 10 carbon (s), in particular from 1 to 4.
• the alcohol has more than one -OH functional group and for example, the alcohol may be glycerol (propane-1,2,3-triol).
• the molar ratio catalyst according to the invention / fatty acids is between 0.001 and 0.5, preferably between 0.01 and 0.2.
• the number of moles of fatty acid is measured by acid-base assay by potentiometry and is expressed in moles per gram of fatty acids present in the starting material. This value is then multiplied by the catalyst / fatty acid molar ratio to determine the amount of catalyst to be added.
• the molar ratio alcohol / fatty acids is between 1 and 20, preferably between 4 and 10.
• the esterification reaction of the fatty acids can be carried out at any temperature but preferably at temperatures between 50 ° C and 200 ° C, more generally at temperatures between 60 ° C and 120 ° C, preferably between 60 ° C and 80 ° C.
• the esterification reaction of the fatty acids may be carried out at any pressure, but preferably at a pressure of between 10 4 Pa (0.1 bar absolute) and 2.10 6 Pa ( 20 bar absolute), more generally between atmospheric pressure and 10 6 Pa (10 bar absolute) and very particularly preferably at atmospheric pressure.
• the reaction time for the esterification of fatty acids can vary in large proportions and is generally between a few minutes and a few hours, for example between 10 minutes and 6 hours, typically between 30 minutes and 180 minutes.
• the esterification reaction may be carried out batchwise or continuously.
• the catalyst according to the invention is added to the mixture or separately in the reaction medium. It can be added alone or co-fed with the source of fatty acids (oil, animal fat, etc.) and / or alcohol.
• the reaction can be carried out in one or more reactors, between 2 and 15, more generally 2 to 10 reactors, more generally still 2 to 5 reactors, arranged in parallel or in cascade. According to one particular embodiment, the batch process with several cascaded reactors is preferred.
• the water formed is removed by any method well known to those skilled in the art, for example as it is formed, for example by heating.
• removal of water may result in removal of all or part of the solvent, particularly when the solvent is an alcohol.
• the free fatty acids used come from vegetable oil to obtain biofuel, including biodiesel.
• the biodiesel is obtained after a transesterification step, as described above. If a step of neutralization of this biodiesel is necessary, it is possible to use the acid phase obtained at the end of the esterification reaction of the free fatty acids and after removal of the alcohol.
• the esterification reaction of fatty acids according to the invention also provides products that can be used in various fields such as cosmetics, lubricants, agrochemicals, pharmacy, cleaning, etc.
• composition comprising:
• APTS para-toluenesulphonic acid
• the above composition is prepared from a 70% by weight aqueous solution of AMS LC from Arkema, introduced into a double jacket reactor.
• the para-toluenesulphonic acid at 89% by weight is a solid which is added all at once at room temperature, then the medium with stirring is heated to 40 ° C until solubilization of para-toluenesulphonic acid.
• composition thus prepared is used as esterification catalyst in the example below.
• An industrial mixture comprising an oil comprising triglycerides and 94% by weight of free fatty acids (FFA for "Free Fatty Acids") with an average molecular weight of fatty acids at 268 ⁇ 1 g.mol "1 is used. .
• the methanol / FFA molar ratio is equal to 8.
• the molar catalyst / FFA ratio is equal to 0.175.
• the reaction mixture is heated to 70 ° C and then introduced the catalyst prepared above.
• reaction mixture is stirred for 2 hours at 70 ° C and then decanted and left overnight at 70 ° C.
• the aqueous and organic phases are analyzed according to the methods described below.
• the FFA and the catalyst in the organic phase are determined by potentiometry in the following manner: in a beaker, about 1.5 g of organic phase are introduced, then the mixture is made up to 50 ml with the toluene mixture. isopropanol / water in the proportions 500/495/5 by volume.
• the potentiometric assay is carried out with 0.1 mol.L -1 potassium hydroxide (KOH) in ethanol with a DG1 13-SC no. 2 electrode and a T50 titrator, both from Mettler Toledo. .
• the determination makes it possible to accurately determine, on the one hand, the amount of residual catalyst in the organic phase in moles per gram and, on the other hand, the residual fatty acid content in the organic phase in% by weight. .
• the acid-base dosage makes it possible to obtain 2 potential jumps: the first jump corresponds to the catalyst and the second jump corresponds to the residual fatty acids. Results:
• composition according to the invention a lower percentage of residual FFA is obtained than that obtained with the AMS alone or the APTS alone.

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• 2017
  • 2017-11-20 EP EP17816907.4A patent/EP3544731A1/de active Pending
  • 2017-11-20 KR KR1020197017954A patent/KR102289779B1/ko active IP Right Grant
  • 2017-11-20 BR BR112019009474-1A patent/BR112019009474B1/pt active IP Right Grant
  • 2017-11-20 MY MYPI2019002862A patent/MY192473A/en unknown
  • 2017-11-20 WO PCT/FR2017/053174 patent/WO2018096249A1/fr unknown
  • 2017-11-20 US US16/463,548 patent/US10780433B2/en active Active
  • 2017-11-20 CN CN201780072990.1A patent/CN109982776A/zh active Pending
• 2019
  • 2019-05-10 PH PH12019501046A patent/PH12019501046A1/en unknown

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