EP2398758A1 - Reaktivextraktion von freien organischen säuren aus deren ammoniumsalzen - Google Patents

Reaktivextraktion von freien organischen säuren aus deren ammoniumsalzen

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Publication number
EP2398758A1
EP2398758A1 EP10704922A EP10704922A EP2398758A1 EP 2398758 A1 EP2398758 A1 EP 2398758A1 EP 10704922 A EP10704922 A EP 10704922A EP 10704922 A EP10704922 A EP 10704922A EP 2398758 A1 EP2398758 A1 EP 2398758A1
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EP
European Patent Office
Prior art keywords
acid
organic
alkyl
group
extraction
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Application number
EP10704922A
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German (de)
English (en)
French (fr)
Inventor
Christoph Kobler
Dieter Buss
Axel Ronneburg
Christoph Weckbecker
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Evonik Operations GmbH
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Evonik Degussa GmbH
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Publication of EP2398758A1 publication Critical patent/EP2398758A1/de
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F9/00—Compounds containing elements of Groups 5 or 15 of the Periodic Table
    • C07F9/02—Phosphorus compounds
    • C07F9/28—Phosphorus compounds with one or more P—C bonds
    • C07F9/38—Phosphonic acids [RP(=O)(OH)2]; Thiophosphonic acids ; [RP(=X1)(X2H)2(X1, X2 are each independently O, S or Se)]
    • C07F9/3804—Phosphonic acids [RP(=O)(OH)2]; Thiophosphonic acids ; [RP(=X1)(X2H)2(X1, X2 are each independently O, S or Se)] not used, see subgroups
    • C07F9/3834—Aromatic acids (P-C aromatic linkage)
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C303/00—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides
    • C07C303/02—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides of sulfonic acids or halides thereof
    • C07C303/22—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides of sulfonic acids or halides thereof from sulfonic acids, by reactions not involving the formation of sulfo or halosulfonyl groups; from sulfonic halides by reactions not involving the formation of halosulfonyl groups
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C319/00—Preparation of thiols, sulfides, hydropolysulfides or polysulfides
    • C07C319/14—Preparation of thiols, sulfides, hydropolysulfides or polysulfides of sulfides
    • C07C319/20—Preparation of thiols, sulfides, hydropolysulfides or polysulfides of sulfides by reactions not involving the formation of sulfide groups
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/02—Preparation of carboxylic acids or their salts, halides or anhydrides from salts of carboxylic acids
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/42—Separation; Purification; Stabilisation; Use of additives
    • C07C51/48—Separation; Purification; Stabilisation; Use of additives by liquid-liquid treatment
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C2602/00—Systems containing two condensed rings
    • C07C2602/36—Systems containing two condensed rings the rings having more than two atoms in common
    • C07C2602/42—Systems containing two condensed rings the rings having more than two atoms in common the bicyclo ring system containing seven carbon atoms

Definitions

  • the present invention relates to a novel, improved process for the preparation and isolation of free organic acids such as carboxylic, sulfonic, phosphonic and especially of alpha-hydroxycarboxylic acids from their corresponding ammonium salts.
  • Organic acids include, but are not limited to, the group of substituted carboxylic (I-III), sulfonic (IV) and phosphonic acids (V):
  • Hydroxycarboxylic acids are specific carboxylic acids that have both a carboxyl group and a hydroxyl group. Most naturally occurring representatives are alpha-hydroxycarboxylic acids, i. the hydroxyl group is seated on a carbon atom adjacent to the carboxyl group.
  • alpha-hydroxycarboxylic acids are also 2-hydroxyisobutyric acid as a precursor for methacrylic acid and methacrylic acid esters. These find their main application in the production of polymers and copolymers with other polymerizable compounds.
  • a likewise commercially important alpha-hydroxycarboxylic acid is the 2-hydroxy-4-methylthiobutyric acid, which is commonly referred to as methionine hydroxy analog (MHA) and in animal nutrition in addition to the essential amino acid methionine especially in monogastric animals such as poultry and pigs important role plays.
  • MHA methionine hydroxy analog
  • Racemic MHA can be used directly as a feed additive because in some species under in vivo conditions a conversion mechanism exists that converts both enantiomers of MHA to the natural amino acid L-methionine.
  • the 2-hydroxy-4-methylthiobutyric acid is first with Using a nonspecific oxidase oxidized to ⁇ -keto-methionine and then further converted with an L-transaminase to L-methionine. This increases the available amount of L-methionine in the organism, which can then be available to the animal for growth.
  • hydroxycarboxylic acids Another class of hydroxycarboxylic acids are the beta-hydroxycarboxylic acids having the general formula Ib:
  • Beta-hydroxycarboxylic acids are, for example, 3-hydroxypropionic acid, 3-hydroxybutyric acid, 3-hydroxyvaleric acid, 3-hydroxyhexanoic acid and 3-hydroxyisobutyric acid.
  • the latter like 2-hydroxyisobutyric acid, can serve as a precursor for the technically important products methacrylic acid and methacrylic acid esters.
  • alpha-hydroxycarboxylic acids are preferably prepared from the cyanohydrins on which they are based with the aid of mineral acids, e.g. Hydrochloric acid, phosphoric acid or preferably prepared with sulfuric acid.
  • Isolation of the free acid is then neutralized only the mineral acid used for the hydrolysis with a Base, preferably ammonia.
  • a Base preferably ammonia.
  • the total mineral acid and the base used for neutralization fall in these methods forcibly in at least stoichiometric and thus very large amounts in the form of mineral salts, usually as ammonium sulfate to.
  • Another chemical method is the hydrolysis of cyanohydrin with inorganic bases, e.g. Sodium hydroxide.
  • inorganic bases e.g. Sodium hydroxide.
  • a mineral acid must be added in stoichiometric amounts to release the alpha-hydroxycarboxylic acid.
  • the hydrolysis of cyanohydrins with titanium dioxide as a catalyst up to the stage of the ammonium salt, the hydrolysis of cyanohydrins with titanium dioxide as a catalyst. The salt problem remains the same.
  • Mono-, di- and tricarboxylic acids as well as alpha and beta hydroxycarboxylic acids can be produced by fermentation with the aid of microorganisms or enzymatically.
  • the organic acids accumulate as ammonium salt.
  • the release is carried out by adding the stoichiometric amount of a mineral acid.
  • di- or tricarboxylic acids it is even necessary to add two or three times the stoichiometric amount of a mineral acid. This also produces very large amounts of ammonium salts, which in turn must be recycled consuming or expensive to dispose of.
  • a small amount of water is added to an ammonium salt of an unsaturated fatty acid and the mixture is heated at a total reflux (80 ° C.) or above in organic solvents to free or remove ammonia to give the unsaturated fatty acid.
  • JP7330696 a 10-80% aqueous solution of an ammonium salt of an acidic amino acid is heated with the addition of water. Ammonia and water distil off and the amino acid is released.
  • Dissociation constant has.
  • US patent 6066763 describes a process for the production of alpha-hydroxycarboxylic acids which does not require the inevitable formation of large amounts of salts which are not or only poorly settleable.
  • the starting materials used are the ammonium salts of the corresponding alpha-hydroxycarboxylic acids obtainable with the aid of enzymes (nitrilases) from the corresponding cyanohydrins.
  • the salt is heated in the presence of water and a solvent.
  • Preferred solvents have a boiling point> 40 ° C and form an azeotrope with water. By distilling off the azeotropic mixture, ammonia is released, which escapes in gaseous form via the condenser.
  • the corresponding alpha-hydroxycarboxylic acid accumulates in the bottom of the distillation unit.
  • large quantities of the initially released alpha-hydroxycarboxylic acid are converted into dimers and polymers of the relevant alpha-hydroxycarboxylic acid by intra- as well as intermolecular esterification. These must then be converted again by heating with water under elevated pressure in the relevant monomeric alpha-hydroxycarboxylic acid.
  • Another disadvantage is the long residence times in both process stages. They are in the examples mentioned at 4 hours. Since at stage 1 the solvent is kept boiling all the time, the steam consumption is uneconomically high. The reason for this is the more difficult with increasing depletion of ammonia release of alpha-hydroxycarboxylic acid. She does not succeed 100%.
  • the obtained alpha-hydroxycarboxylic only have a purity of about 80%, so that further purification by means of liquid-liquid extraction or crystallization is usually necessary.
  • the ammonium salt solutions of the alpha-hydroxycarboxylic acids are brought under reduced pressure to a concentration> 60%.
  • the conversion into dimeric or polymeric esters of the corresponding alpha-hydroxycarboxylic acids should be less than 20%.
  • a gas preferably water vapor
  • ammonia is released and expelled.
  • 2-hydroxy-4-methylthiobutyric acid 70% free acid are achieved, the remainder consists of unreacted ammonium salt of 2-hydroxy-4-methylthiobutyric acid and the corresponding dimeric ester.
  • US 2003/0029711 A1 describes a process for obtaining organic acids, inter alia from aqueous solutions of the ammonium salts with addition of a hydrocarbon as entraining agent.
  • a gaseous product stream is obtained which contains an azeotrope consisting of the organic acid and the entraining agent.
  • additional steps such as condensation and additional distillations must be performed.
  • this process also requires the addition of additional chemicals (entrainers), which makes the process considerably more costly, especially for an industrial-scale application.
  • 6,291,708 B1 describes a process in which an aqueous solution of an ammonium salt is mixed with a suitable alcohol and this alcohol-water mixture is then heated under elevated pressure to thermally decompose the ammonium salt to the free acid and ammonia.
  • a suitable gas is brought into contact with the alcohol-water mixture as an entraining agent, so that a gaseous product stream containing ammonia, water and a portion of the alcohol is expelled, while at least 10% of the alcohol remain in the liquid phase and with the free acid to the corresponding ester.
  • the disadvantages of this process include the need for additional chemicals (alcohol and a gas entrainer) and the partial conversion of the resulting free carboxylic acid to the ester, which in turn must be hydrolyzed to yield the free carboxylic acid.
  • Solvents are ethers, ketones and trialkyl phosphine oxides, also in mixtures with various hydrocarbons. The solvent is removed by distillation and the resulting 2-hydroxy-4-methylthiobutyramide is hydrolyzed base. As bases serve tertiary amines by
  • the technical problem is solved by a process for the reaction of ammonium salts of organic acids and conversion into the respective free organic acid, wherein an aqueous solution of the ammonium salt is brought into contact with an organic extractant and the salt cleavage takes place at temperatures and pressures at which the aqueous solution and the extractant are in the liquid state, wherein a stripping medium or Schleppgas is introduced to remove NH 3 from the aqueous solution and at least a portion of the formed free organic acid passes into the organic extractant.
  • the invention provides a process wherein the ammonium salt of organic acids is converted by means of reactive extraction using a stripping medium or towing gas, for example by stripping the ammonia with steam or nitrogen, into the free organic acid, which subsequently into the organic extractant passes. It is preferred that at least 50%, preferably at least 80%, more preferably at least 90% and most preferably at least 95% of the free organic acid formed is transferred to the organic extractant.
  • the reaction is carried out at pressures of from 0.01 bar to 200 bar, especially from 0.01 bar to 20 bar, more preferably from 0.1 bar to 5 bar. It is further preferred that the salt cleavage at temperatures of 5 ° C to 300 0 C, more preferably from 20 0 C to 300 ° C, more preferably from 40 0 C to 200 ° C, particularly preferably from 50 0 C to 130 0 C. is carried out.
  • the temperature has a great influence on the rate of formation of the free acid and its final yield.
  • the temperature depends on the extractant used and, according to the invention, is below the boiling point of the aqueous solution or of a possible azeotrope, the boiling point of the aqueous solution or of an optionally forming azeotrope being of course dependent on the particular applied pressure.
  • the salt splitting is carried out in the process according to the invention at temperatures and pressures at which the aqueous solution and the
  • Extractants are liquid, not solid and non-gaseous, i. below the boiling point of the aqueous solution or an optionally forming azeotropic mixture which depends on the respective applied pressure. According to the invention, the initial concentration of
  • Ammonium salt of the organic acid in the aqueous solution used preferably in the range of 90 wt .-% to 1 wt .-%, more preferably from 75 wt .-% to 5 wt .-% and most preferably from 60 wt .-% to 10% by weight. In the course of the reaction of salt splitting, the corresponding concentration of the salt decreases.
  • the extractant used is a solvent which is sparingly or not at all miscible with water.
  • the weight ratio of aqueous solution and organic extractant is from 1: 100 to 100: 1, particularly preferably from 1:10 to 10: 1, very particularly preferably from 1: 5 to 5: 1.
  • the organic acid may be selected from the group monocarboxylic acid, dicarboxylic acid, tricarboxylic acid, ascorbic acid, sulfonic acid, Phosphonic acid, hydroxycarboxylic acid, in particular alpha-hydroxycarboxylic acid or beta-hydroxycarboxylic acid.
  • the organic acid formed can be recovered from the organic extractant.
  • the organic acid corresponds to a carboxylic acid of the general formula I,
  • X 1 is an organic radical selected from the group consisting of unsubstituted and mono- or polysubstituted, branched and straight-chain alkyl, cycloalkyl, alkenyl having one or more double bonds, alkynyl having one or more triple bonds, aryl, alkylaryl, Arylalkyl, arylalkenyl, alkyloxyalkyl, hydroxyalkyl and alkylthioalkyl radicals.
  • X 1 is an organic radical selected from the group consisting of (C 1 -C 8 ) -alkyl, (C 3 -C 18) -cycloalkyl, (C 2 -C -26) -alkenyl having one or more double bonds, (C2-C26) alkynyl having one or more triple bonds, (C 6 -C 0) aryl, in particular phenyl, (Ci-C 8) alkyl (C 6 -C 0) aryl, ( C 6 -C 0) aryl (Ci-C 8) - alkyl, (C 6 -C 0) aryl (C 2 -C 26) alkenyl, (Ci-C 8) -alkyloxy- ( Ci-Ci 8 ) -alkyl, (Ci-Ci 8 ) -hydroxyalkyl and (Ci-Ci 8 ) - alkylthio (Ci-Ci 8 )
  • X 1 is preferably CR 1 R 2 R 3 , where R 1 is H, OH, OR 4 , NH 2 , NHR 4 , NR 4 R 5 , Cl, Br, J, F, where R 2 , R 3 , R 4 and R 5 are independently selected from the group consisting of H, unsubstituted and mono- or polysubstituted, branched and straight-chain (Ci-Ci 8 ) alkyl, (C 3 -C 8 ) -cycloalkyl , (C 2 -C 26) alkenyl having one or more double bonds, (C 6 -C 0) aryl, in particular phenyl, (C 1 -C 8 ) -alkyl- (C 1 -C 10) -aryl-, (C 1 -C 10) -aryl (C 1 -C 8 ) -alkyl, in particular benzyl-, (C 1 -C 8 ) - alkyloxy
  • the organic acid is preferably selected from the group consisting of acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, palmitic acid, stearic acid, omega-3 fatty acids such as linolenic acid, omega-6 fatty acids such as linoleic acid and arachidonic acid , Omega-9 fatty acids such as oleic and nervonic acid, salicylic acid, benzoic acid, ferulic acid, cinnamic acid, vanillic acid, gallic acid, hydroxycinnamic acids, hydroxybenzoic acids, 3-hydroxypropionic acid.
  • the organic acid corresponds to a dicarboxylic acid of the general formula II,
  • X 2 is an organic radical selected from the group consisting of unsubstituted and mono- or polysubstituted, branched and straight-chain alkanediyl, cycloalkanediyl, alkenediyl having one or more double bonds, alkynediyl having one or more triple bonds, aryldiyl, alkylaryldiyl, arylalkanediyl , Arylalkendiyl, alkyloxyalkanediyl,
  • X 2 is defined as follows: an organic radical selected from the group unsubstituted and mono- or polysubstituted with substituents selected from the group containing OH, OR 4 , NH 2 , NHR 4 , NR 4 R 5 , Cl , Br, J and F, substituted, branched and straight-chain (C 1 -C 8 ) -alkanediyl, (C 3 -C 8 ) -cycloalkanediyl, (C 2 -C 2 6) -alkendiyl having one or more double bonds, (C 2 -C 26) alkynediyl having one or more triple bonds, (C 6 -C 0) aryldiyl, phenyldiyl particularly, (Ci-C 8) alkyl (C 6 -C 0) aryldiyl , (C 6 -C 0) aryl (Ci-Ci 8) -alkane
  • the organic acid is preferably selected from
  • the organic acid is a tricarboxylic acid of general formula III,
  • X 3 is an organic radical selected from the group consisting of unsubstituted and mono- or polysubstituted, branched and straight-chain alkanetriyl, cycloalkanetriyl, alkynediyl having one or more double bonds, alkynetriyl having one or more triple bonds, aryltriyl, alkylaryltriyl-, Arylalkanetriyl, arylalkentriyl, alkyloxyalkanetriyl, hydroxyalkanetriyl and alkylthioalkanetriyl radicals.
  • the suffix "- triyl” indicates that the three carboxylic acid groups of the tricarboxylic acid are bonded to this group
  • the carboxylic acid groups may independently be bonded to any carbon atoms of the organic group, for example geminal, vicinal or non-contiguous carbon atoms Carbon atoms to which the carboxylic acid groups are attached, may be both in the terminal position, and within the radical.
  • X 3 is defined as follows: unsubstituted and mono- or polysubstituted with substituents selected from the group comprising OH, OR 4 , NH 2 , NHR 5 , NR 4 R 5 , Cl, Br, J and F, substituted, branched and straight chain (Ci-Ci 8 ) alkanetriyl, (C3-C18) -cycloalkanetriyl, (C2-C26) alkynetriyl having one or more double bonds, (C2-C26) -alkynyltriyl- with one or more triple bonds, (C 6 -C 0) -Aryltriyl-, particularly Phenyltriyl-, (Ci-C 8) alkyl (C 6 -C 0) -aryltriyl-, (C 6 -C 0) aryl (Ci- Ci 8) -alkantriyl-, (C 6 -C 0) aryl (
  • the organic radicals in a preferred embodiment, the organic
  • Acid selected from the group of citric acid, cyclopentane-1, 2, 3-tricarboxylic acid, cyclopentane-1,2,4-tricarboxylic acid, 2-methylcyclopentane-1,2,3-tricarboxylic acid, 3-methylcyclopentane-1,2,4-tricarboxylic acid ,
  • the organic acid corresponds to a sulfonic acid of the general formula IV,
  • R 6 is an organic radical selected from the group consisting of unsubstituted and mono- or polysubstituted, branched and straight-chain alkyl, cycloalkyl, alkenyl having one or more double bonds, alkynyl having one or more triple bonds, aryl, alkylaryl, arylalkyl -, Arylalkenyl-, Alkyloxyalkyl-, hydroxyalkyl and Alkylthioalkylreste represents.
  • R 6 is defined as follows: unsubstituted and mono- or polysubstituted with substituents selected from the groups containing OH, OR 4 , NH 2 , NHR 4 , NR 4 R 5 , Cl, Br, J and F, substituted, branched and straight-chain (C 1 -C 8 ) -alkyl, (C 3 -C 8 ) -cycloalkyl, (C 2 -C 26 ) -alkenyl having one or more double bonds, (C 2 -C 26 ) - alkynyl having one or more triple bonds, (C 6 - Ci 0) aryl, in particular phenyl, (Ci-C 8) alkyl (C 6 -C 0) - aryl-, (C 6 -C 0) aryl (Ci-C 8) alkyl, (C 6 -C 0) aryl (C 2 -C 26) - alkenyl, (Ci
  • the organic acid is selected from the group p-toluenesulfonic acid, camphor-10-sulfonic acid, benzenesulfonic acid, dodecylbenzenesulfonic acid, naphthalenesulfonic acids, phenolsulfonic acids.
  • the organic acid is a phosphonic acid of the general formula V,
  • R 7 is an organic radical selected from the group consisting of unsubstituted and mono- or polysubstituted, branched and straight-chain alkyl, cycloalkyl, alkenyl having one or more double bonds, alkynyl having one or more triple bonds, aryl, alkylaryl, arylalkyl -, Arylalkenyl-, Alkyloxyalkyl-, hydroxyalkyl and Alkylthioalkylreste represents.
  • R 7 is defined as follows: unsubstituted and mono- or polysubstituted with substituents selected from the groups containing OH, OR 4 , NH 2 , NHR 4 , NR 4 R 5 , Cl, Br, J and F.
  • the organic acid is selected from the group consisting of 1-aminopropylphosphonic acid, aminomethylphosphonic acid, xylylphosphonic acids, phenylphosphonic acid, 1-aminopropylphosphonic acid, toluenephosphonic acid.
  • the organic acid is an alpha-hydroxycarboxylic acid of general formula Ia,
  • R 8 and R 9 are independently selected from the group consisting of H, OH, OR 4 , NH 2 , NHR 4 , NR 4 R 5 , Cl, Br, J, F, unsubstituted and mono- or polysubstituted, branched and straight-chain alkyl, cycloalkyl, alkenyl having one or more double bonds, alkynyl having one or more triple bonds, aryl, alkylaryl, Arylalkyl, arylalkenyl, alkyloxyalkyl, hydroxyalkyl and alkylthioalkyl radicals, where R 4 and R 5 are independently selected from the group comprising H, unsubstituted and mono- or polysubstituted, branched and straight-chain (C 1 -C 8 ) -alkyl radicals , (C3-C18) - cycloalkyl, (C2-C26) alkenyl having one or more double bonds, (C 6 -
  • R 8 and R 9 are independently selected from the group unsubstituted and mono- or polysubstituted with substituents selected from the groups containing OH, OR 4 , NH 2 , NHR 4 , NR 4 R 5 , Cl, Br , J and F, unsubstituted, branched and straight chain (Ci-C 8) - alkyl, (C 3 -C 8) cycloalkyl, (C 2 -C 26) alkenyl having one or more double bonds, (C 2 -C 26) alkynyl with one or more triple bonds, (C 6 -C 0) aryl, in particular phenyl, (Ci-C 8) alkyl (C 6 -C 0) aryl, (C 6 -C 0) - aryl (Ci-C 8) alkyl, (C 6 -C 0) aryl (C 2 -C 26) alkenyl, (Ci Ci 8)
  • the organic acid is selected from the group consisting of 2-hydroxyisobutyric acid, 2-hydroxy-4-methylthiobutyric acid, lactic acid, glycolic acid, malic acid, tartaric acid, gluconic acid, glyceric acid.
  • the organic acid is a beta-hydroxycarboxylic acid of the general formula Ib,
  • R 10 , R 11 , R 12 and R 13 are independently selected from the group consisting of H, OH, OR 4 , NH 2 , NHR 4 , NR 4 R 5 , Cl, Br, J, F, unsubstituted and or polysubstituted, branched and straight-chain alkyl, cycloalkyl, alkenyl having one or more double bonds, alkynyl having one or more triple bonds, aryl, alkylaryl, arylalkyl, arylalkenyl, alkyloxyalkyl, hydroxyalkyl and alkylthioalkyl radicals, where R 4 and R 5 are independently selected from the group consisting of H, unsubstituted and mono- or polysubstituted, branched and straight-chain (Ci-Ci 8 ) alkyl, (C3-C18) - cycloalkyl, (C2-C26) - alkenyl having one or more double bonds, (C 6
  • 3-hydroxyisobutyric acid like 2-hydroxyisobutyric acid, can serve as a precursor for methacrylic acid and methacrylic acid esters.
  • Stripping medium or towing gas steam air, gases, preferably Natural gas, methane, oxygen, inert gas, preferably nitrogen, helium, argon or mixtures thereof used.
  • a Strippmedium- or Schleppgasmenge based on the aqueous ammonium salt solution used between 1 l / kg and 10000 l / kg, especially between 10 l / kg and 500 l / kg and most especially between 20 l / kg and 100 l / kg preferred.
  • the organic extractant is selected from the group consisting of straight-chain or branched aliphatic ketones having 5 to 18 carbon atoms, heterocyclic ketones having 5 to 18 carbon atoms, straight-chain or branched aliphatic alcohols having 4 to 18 carbon atoms , heterocyclic alcohols having 5 to 18 carbon atoms, straight-chain or branched aliphatic alkanes having 5 to 18 carbon atoms, cycloalkanes having 5 to 14 carbon atoms, straight-chain or branched ethers having 4 to 18 carbon atoms, with Halogen atoms or hydroxyl-substituted aromatics, halogen-substituted straight-chain or branched alkanes having 1 to 18 carbon atoms, halogen atoms-substituted cycloalkanes having 5 to 14 carbon atoms, preferably isobutyl methyl ketone, isopropyl methyl ketone, ethyl
  • the free acid is recovered from the extractant-laden extractant by a separation process selected from distillation, rectification, crystallization, back-extraction, chromatography, adsorption, or membrane processes.
  • the process according to the invention has the advantage of being more cost-effective, since the expensive work-up and / or disposal of equimolar amounts of salt is eliminated and, on the other hand, it is environmentally friendly and resource-saving through the back integration of the liberated ammonia into a production process and the closed cycle of the extractant.
  • adjuvants such as e.g. Sulfuric acid to liberate the free acid from the ammonium salt is eliminated as well as additional higher cost reaction steps, e.g. the Umamintechnik of the ammonium salt with a secondary or tertiary amine or the
  • the invention described herein comprises an improved process for the release of a substituted or unsubstituted organic acid, preferably a carboxylic (I-III), sulfonic acid (IV) or phosphonic acid (V), particularly preferably an alpha-hydroxycarboxylic acid (Ia) from the latter Ammonium salt by release and removal of ammonia and simultaneous extraction of the liberated acid with a suitable extractant from the aqueous phase.
  • a substituted or unsubstituted organic acid preferably a carboxylic (I-III), sulfonic acid (IV) or phosphonic acid (V), particularly preferably an alpha-hydroxycarboxylic acid (Ia) from the latter Ammonium salt by release and removal of ammonia and simultaneous extraction of the liberated acid with a suitable extractant from the aqueous phase.
  • This procedure corresponds to a reactive extraction.
  • Reactive extraction of an organic acid from its aqueous ammonium salt solution may be accomplished by the use of a stripping medium such as e.g. Nitrogen, air, steam or inert gases, e.g. Argon can be significantly improved.
  • the liberated ammonia is removed from the aqueous solution by the continuous flow of gas and can be re-fed to a production process.
  • the free acid may be recovered from the extractant by a process such as distillation, rectification, crystallization, back-extraction, chromatography, adsorption or by a membrane process.
  • Extraction is understood as meaning a substance separation process in which the enrichment or recovery of substances from mixtures is achieved with the aid of selectively acting solvents or extraction agents.
  • the separation of substances based on the different distribution of mixture components is based on two or more co-existing phases, which normally result from the limited miscibility of the individual components into one another (miscibility gap).
  • the mass transfer via the phase interface takes place by diffusion until a stable final state - the thermodynamic equilibrium - has been established. After reaching equilibrium, the phases must be mechanically separated. Since these again consist of several components, are in the Generally further separation processes (eg distillation, crystallization or extraction) downstream for workup.
  • the extraction of at least one reaction is superimposed. This influences the thermodynamic equilibria and thus improves the mass transfer between the phases.
  • the resulting free organic acid is immediately extracted from the aqueous solution by a suitable extractant. As a result, no appreciable reduction in the pH of the aqueous solution occurs. The release of additional ammonia is not hindered. The remaining proportion of ammonium salt in the aqueous phase is less than 1%. The released organic acid is completely extracted.
  • the concentration of the ammonium salt used has an influence on the extraction rate.
  • the reactive extraction is not limited to the use of isobutyl methyl ketone as extractant. It is possible to use any organic solvent which is immiscible or only sparingly miscible with water, such as alcohols, ethers, ketones or hydrocarbons or mixtures thereof.
  • the reactive extraction using a stripping medium or towing gas is also applicable to other hydroxycarboxylic acids.
  • examples include the commercially significant lactic acid and 2-hydroxyisobutyric acid used in plastic production as a precursor to MMA.
  • the present invention not only restricts the release of hydroxycarboxylic acids from their ammonium salts, but also includes other substituted or unsubstituted carboxylic acids, e.g. Valeric acid and sulfonic acids, e.g. (+) - camphor-10-sulfonic acid and phosphonic acids, e.g. Toluenephosphonic acid.
  • Toluenephosphonic acid ammonium salt solution could at 80 0 C with isobutyl methyl ketone as the extraction agent and with 6 1 nitrogen per hour as a carrier gas after 46 hours extraction time found 43% of the toluenephosphonic acid used (Example 13).
  • the extraction vessel of the perforator is filled halfway with an aqueous ammonium salt solution of an organic acid and filled with an extractant to the overflow to the template.
  • the template itself is also half filled with extractant.
  • the extraction vessel is equipped with an inserted distributor and a gas inlet tube equipped with a frit.
  • the distributor is rotated by a magnetic coupling.
  • a stripping gas eg nitrogen, is introduced via the gas inlet tube.
  • the extractant supplied to the distributor from the condenser from above via a tube by distillation from the original is centrifugally ejected from small holes of a distributor ring as fine droplets into the aqueous ammonium salt solution to be extracted.
  • the ammonia is driven out of the aqueous phase by the gas flow. Due to the co-rotation of the aqueous ammonium salt solution to be extracted reaches the finely divided, loaded with the extracted free organic acid extractant only after a prolonged residence time in the aqueous phase, the deposition zone of the perforator and runs back into the template (distilling), from which the solvent by renewed Evaporation is returned to the extraction circuit.
  • the template collects the free organic acid.
  • the liberated ammonia stream is removed with the stripping gas via the attached intensive cooler and collected in an aqueous sulfuric acid trap.
  • An apparatus improvement is the countercurrent extractor ( Figure 2).
  • the tempered aqueous ammonium salt solution of an organic acid is charged from above and pumped in a circle.
  • the extractant is pumped into the reaction tube in countercurrent and introduced the towing gas into the system.
  • the finely divided drops of extractant absorb the released organic acid.
  • the lighter organic phase is separated.
  • the Extracting agent re-introduced into the circulation.
  • the towing gas and the liberated, expelled ammonia are separated overhead.
  • Extraction column and the amount of entrained drag gas and the flow rates of the extractant and the aqueous ammonium salt solution depends on the extractant used and should be below the boiling point of a possible azeotrope.
  • An apparatus used on an industrial scale in a liquid-liquid extraction on the countercurrent principle is a mixer-settler apparatus.
  • the carrier and the extractant are driven in opposite directions through the mixer tap.
  • the highly loaded carrier stream is contacted with already enriched extractant, thereby providing a first refining.
  • the loading of the carrier stream decreases.
  • the loading of the extractant stream thus contacted decreases in the same direction so that finally in the last stage the already highly depleted raffinate is dispersed with fresh unloaded extractant.
  • countercurrent process as a strong depletion of the raffinate is achieved with low amounts of extractant, making this variant is very economical.
  • the apparatus shown ( Figure 4 for high boilers as extractant and Figure 5 for low boilers) are used for the cleavage of ammonium salts of organic acids in ammonia and the corresponding organic acids, which thermal cracking can take place under mild conditions, so it does not lead to decomposition of the organic acids comes.
  • the apparatus consists of a column with n bottoms, whose bottoms are preferably configured as bell or valve bottoms, so that there is no or only to a very limited extent a direct rainthrough of the liquid phases from the upper bottoms to the underlying soils.
  • the column is flowed through from bottom to top with a stripping medium, which is preferably introduced below into the column or below the lowest bottom becomes.
  • the stripping medium may preferably be water vapor which is recovered by heating the downwardly conducted aqueous phase, or the stripping medium may also be an inert gas such as nitrogen or another gas which coexists with
  • Ammonia by interactions forms a mixture that is easy to convert into the gas phase.
  • the design of the trays is preferably such that the aqueous and the organic phase are conducted together from the inlet on the ground to the outlet through suitable baffles, to backmixing or
  • Phase interface easily converted into the gas phase and the resulting organic acid can be extracted quickly from the aqueous phase into the organic phase.
  • the aqueous phase containing the ammonium salt and the organic acid-absorbing organic phase are added together to the uppermost plate (No. 1) of the column and mixed.
  • the aqueous phase most heavily laden with the ammonium salt is combined with the organic acid-absorbing organic phase behind the separation process belonging to the bottom below (n ° 2) on the top soil. Due to the thermal splitting off of the ammonia, this gas passes through the contact with the gas phase on each floor into the gas phase and the organic acid passes from the aqueous to the organic phase.
  • the two phases are separated from each other in a suitable separation process.
  • This separation process may be a phase separator in the case of low mutual solubility of organic and aqueous phase.
  • a temperature change can take place before the separation process.
  • Other separation processes such as distillation, rectification, membrane processes, crystallization, adsorption, chromatography, etc. are also possible.
  • the organic acid may be separated from the solvent by one or more other separation techniques such as distillation, rectification, membrane processes, crystallization, adsorption, chromatography, etc.
  • the liberated solvent can then be fed back into the column for extraction.
  • the aqueous phase after the top soil separation process (# 1) gets into the soil below (# 2) and is in turn combined with the organic acid receiving organic phase behind the separation process associated with the soil below (# 3).
  • the fresh organic solvent recycled from the previous separation process is combined on the lowermost soil (# N) together with the aqueous phase from the overlying soil.
  • the organic solvent can also be vaporized as described above and used as a dragging medium.
  • the solvent is either fresh in the lower
  • All of the mentioned processes of the present invention are preferably carried out in an aqueous medium.
  • processes of the present invention may be carried out in batch processes known in the art or in continuous processes.
  • the extractant loaded with the free acid can be cooled in a phase separator.
  • the free organic acid separates with the water dissolved in the extractant as a higher concentrated aqueous phase and can be separated.
  • the free acid is present in pure form.
  • the extractant can be directly fed back into the extraction cycle.
  • the loaded with the free acid extractant is heated to boiling in a distillation apparatus of conventional design at atmospheric pressure or reduced pressure and distilled off.
  • This water-containing or anhydrous distillate in the case of an azeotrope-forming solvent can be directly fed back into the extraction cycle.
  • the free acid remains in the distillation bottoms.
  • Another way to separate the free organic acid from the loaded extractant is the back-extraction with water.
  • the extractant loaded with the free organic acid is back extracted from the organic solvent in an extraction apparatus (e.g., Figure 2) with water in a countercurrent extraction.
  • an extraction apparatus e.g., Figure 2
  • the now uncharged organic extractant can again be fed directly into the extraction cycle.
  • the aqueous solution of the free organic acid can be concentrated to the desired concentration by distilling off the water.
  • the separation of the organic extractant may also by Crystallization, adsorption, membrane processes, chromatography, rectification, or the like.
  • Solvent flask was charged with 500 g of isobutyl methyl ketone and heated to boiling (internal temperature 115-117 ° C). The aqueous salt solution was passed continuously 6 1 nitrogen per hour. During the reaction time, analytical samples were taken from the
  • Phase separator (80 0 C) passed into the distillation vessel.
  • the gently distilled isobutyl methyl ketone was fed back into the circulation via the solvent template.
  • the extracted MHA remained with not distilled isobutyl methyl ketone in the
  • the running MHA-containing isobutyl methyl ketone phase was passed over the heated phase separator (80 0 C) in the distillation vessel.
  • the gently distilled isobutyl methyl ketone was fed back into the circulation via the solvent template.
  • the extracted MHA remained with not distilled isobutyl methyl ketone in the
  • FIG. 1 shows the schematic structure of the perforator used for reactive extraction.
  • FIG 2 shows the schematic structure of the extraction apparatus used (countercurrent extractor).
  • FIG. 3 shows the schematic structure of a cascade reactive extraction.
  • FIG. 4 shows the schematic structure of a technical reactive extraction with high-boiling extraction agents.
  • Figure 5 shows the schematic structure of a technical
  • FIG. 6 shows the influence of the stripping medium on the yield of the free organic acid.
  • FIG. 7 shows the influence of the temperature on the yield of the free organic acid.
  • Figure 8 shows the effect of the initial concentration of the ammonium salt of the organic acid on the yield of the respective free organic acid.
  • FIG. 9 shows the influence of different extractants on the yield of the free organic acid.
  • FIG. 10 shows the course of the formation of the free acid using the example of lactic acid.
  • FIG. 11 shows the course of the formation of the free acid on the example of 2-hydroxyisobutyric acid.
  • FIG. 12 shows the course of the formation of the free acid using the example of valeric acid.
  • FIG. 13 shows the course of the formation of the free acid using the example of 2-hydroxy-4-methylthiobutyric acid in the countercurrent reactor.
  • FIG. 14 shows the course of the formation of the free acid using the example of 2-hydroxy-4-methylthiobutyric acid in a countercurrent reactor with different amounts of stripping medium introduced.

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EP10704922A 2009-02-19 2010-02-12 Reaktivextraktion von freien organischen säuren aus deren ammoniumsalzen Withdrawn EP2398758A1 (de)

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DE102009001008A DE102009001008A1 (de) 2009-02-19 2009-02-19 Reaktivextraktion von freien organischen Säuren aus deren Ammoniumsalzen
PCT/EP2010/051787 WO2010094630A1 (de) 2009-02-19 2010-02-12 Reaktivextraktion von freien organischen säuren aus deren ammoniumsalzen

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Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102008002715A1 (de) * 2008-06-27 2009-12-31 Evonik Röhm Gmbh 2-Hydroxyisobuttersäure produzierende rekombinante Zelle
DE102008040193A1 (de) * 2008-07-04 2010-01-07 Evonik Röhm Gmbh Verfahren zur Herstellung freier Carbonsäuren
DE102009009580A1 (de) * 2009-02-19 2010-08-26 Evonik Degussa Gmbh Verfahren zur Herstellung freier Säuren aus ihren Salzen
JP5754785B2 (ja) * 2010-03-26 2015-07-29 バイオアンバー インコーポレイテッド コハク酸二アンモニウム、コハク酸一アンモニウム及び／又はコハク酸を含む発酵培地からコハク酸一アンモニウムの製造、及びコハク酸一アンモニウムからコハク酸への変換方法
US20120021473A1 (en) * 2010-04-01 2012-01-26 Bioamber S.A.S. Processes for producing carboxylic acids from fermentation broths containing their ammonium salts
CN103214053B (zh) * 2013-03-15 2014-11-05 湖南禹之神环保科技有限公司 一种没食子酸生产废水的处理方法
CN104447273B (zh) * 2014-10-27 2016-02-03 天津华津制药有限公司 一种佐匹克隆拆分剂d-(+)-苹果酸的回收方法
WO2016194003A2 (en) * 2015-05-29 2016-12-08 Arvind Mallinath Lali Separation of organic acids from mixtures containing ammonium salts of organic acids
KR102079774B1 (ko) * 2016-11-25 2020-02-20 주식회사 엘지화학 (메트)아크릴산의 연속 회수 방법 및 장치
KR102079775B1 (ko) * 2016-11-25 2020-02-20 주식회사 엘지화학 (메트)아크릴산의 연속 회수 방법 및 장치
CN110622968B (zh) * 2019-08-29 2021-03-19 刘冬 一种大豆疫霉抑制剂及其制备方法
KR102474288B1 (ko) * 2021-04-01 2022-12-05 서울대학교산학협력단 쓰기 간섭 문제를 완화하는 상변화 메모리 모듈

Family Cites Families (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB967352A (en) 1962-05-17 1964-08-19 Distillers Co Yeast Ltd Production of unsaturated aliphatic acids
JPS54115317A (en) 1978-02-25 1979-09-07 Nitto Chem Ind Co Ltd Preparation of acrylic acid or methacrylic acid
JPS6150937A (ja) * 1984-08-20 1986-03-13 Asahi Chem Ind Co Ltd カルボン酸アンモン水溶液からカルボン酸の製造法
DE4341770A1 (de) 1993-12-08 1995-06-14 Basf Ag Verfahren zur Herstellung von Milchsäureestern
JPH07330696A (ja) 1994-06-01 1995-12-19 Mitsubishi Chem Corp 酸性アミノ酸の製造方法
AU1735197A (en) * 1996-02-26 1997-09-10 Nippon Soda Co., Ltd. Process for preparing free alpha-hydroxy acids from ammonium salts thereof
DE19654485A1 (de) * 1996-12-27 1998-07-02 Degussa Verfahren zur Gewinnung von lagerstabiler 2-Hydroxy-4-methylthiobuttersäure (MHA)
WO1999000350A1 (fr) * 1997-06-26 1999-01-07 Nippon Soda Co., Ltd. Procede de production d'acides libres a partir de carboxylates d'ammonium
FR2780968B1 (fr) 1998-07-10 2000-08-18 Rhone Poulenc Nutrition Animal Procede de preparation de l'acide hydroxymethylthiobutyrique
FR2791668B1 (fr) 1999-04-02 2001-05-04 Rhone Poulenc Animal Nutrition Procede de preparation d' beta-hydroxy acides
US6291708B1 (en) * 1999-04-28 2001-09-18 A.E. Staley Manufacturing Co. Process for production of organic acids and esters thereof
DE10040402A1 (de) * 2000-08-18 2002-02-28 Degussa Verfahren zur Herstellung von 2-Hydroxy-4-methylmercaptobuttersäure (MHA)
US6926810B2 (en) 2001-03-15 2005-08-09 A. E. Staley Manufacturing Co. Process for obtaining an organic acid from an organic acid ammonium salt, an organic acid amide, or an alkylamine organic acid complex
ATE393137T1 (de) * 2001-05-07 2008-05-15 Cargill Inc Verfahren zur herstellung von carbonsäuren und deren derivaten
DE10313169A1 (de) * 2003-03-25 2004-10-14 Degussa Ag Verfahren zur anodischen Alkoxylierung von organischen Substraten
DE10315186A1 (de) * 2003-04-03 2004-10-21 Degussa Ag Verfahren zur anodischen Alkoxylierung von organischen Verbindungen
DE10316110A1 (de) * 2003-04-09 2004-10-28 Degussa Ag Verfahren zur Herstellung von 2-Hydroxy-4-methylthio-buttersäure Ammoniumsalz
JP4831394B2 (ja) * 2003-10-09 2011-12-07 独立行政法人産業技術総合研究所 カルボン酸系化合物の製造方法
WO2006124633A1 (en) * 2005-05-13 2006-11-23 Cargill, Incorporated Production of lactic acid
BRPI0719792A2 (pt) * 2006-10-04 2015-04-07 Cargill Inc Ácidos carboxílicos preparados usando um processo de divisão da molécula de sal
DE102006049767A1 (de) 2006-10-21 2008-04-24 Kiefer, Hans, Dr. Verfahren zur Herstellung von 4-Methylmercapto-2-hydoxybuttersäure
DE102006049768A1 (de) 2006-10-21 2008-04-24 Kiefer, Hans, Dr. Verbessertes Verfahren zur Herstellung von 4-Mehylthio-2-hydroxybuttersäure
DE102006052311A1 (de) 2006-11-07 2008-05-08 Kiefer, Hans, Dr. Verbessertes Verfahren zur Herstellung von alpha-Hydroxysäuren
DE102009009580A1 (de) * 2009-02-19 2010-08-26 Evonik Degussa Gmbh Verfahren zur Herstellung freier Säuren aus ihren Salzen

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
None *
See also references of WO2010094630A1 *

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SG2014014104A (en) 2014-05-29
JP2012518022A (ja) 2012-08-09
US20100210871A1 (en) 2010-08-19

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