Abstract: The invention provides a process for the conversion of an extracted carboxylic acid to a non-ionized derivative thereof, comprising contacting a carboxylic acid containing aqueous solution with a water-insoluble amine solvent, to recover acid therefrom and to form an extract carrying amine-bound carboxylic acid, characterized in that said extract is contacted with a concentrated aqueous solution of said same acid of high concentration, whereby additional acid is transferred to said extract to form a loaded extract and said loaded extract is reacted to form a non-ionized derivative of said acid, by reactions known per se, whereby said acid is converted into a non-ionised derivative form and said amine solvent is liberated for recycling.

Abstract: The techniques for processing lactic acid/lactate salt mixtures are provided. Preferred mixtures for processing are obtained from fermentation broths, preferably from fermentation processes conducted at a pH of 4.8 or lower. The techniques generally concern the provision of separated lactic acid and lactate streams, from the mixtures. Preferred techniques of separation and processing of each of the streams are provided.

Abstract: A process is disclosed for purifying an aqueous feed stream comprising a product organic acid, such as lactic acid, and a strong contaminant, such as pyruvic acid or oxalic acid. The molar concentration of the product organic acid in the feed stream typically is at least 20 times greater than the molar concentration of the strong contaminant. The aqueous feed stream is contacted with a first immiscible basic extractant that has at least a 3-fold greater affinity for the strong contaminant than for the product organic acid. The majority of the strong contaminant and some product organic acid become complexed with the first immiscible basic extractant. The complexed first immiscible basic extractant is separated from the aqueous stream, thereby producing a first effluent stream that comprises product organic acid and that has a greater ratio of molar product organic acid to molar strong contaminant than the aqueous feed stream did.

Abstract: The invention relates to a method for the preparation of lactic acid and calcium sulphate, in which (a) an aqueous solution that contains lactate is reacted with sulphuric acid at a temperature that is essentially higher than the transition temperature of calcium sulphate dihydrate (CaSO4.2H2O), with the formation of a mixture that contains calcium sulphate hemihydrate and lactic acid, (b) the mixture from step (a) is subjected to at least one recrystallisation step at a temperature that is essentially lower than the transition temperature of calcium sulphate dihydrate, with the formation of a precipitate of calcium sulphate dihydrate and an aqueous solution of lactic acid, and (c) the precipitate of calcium sulphate dihydrate is separated off from the aqueous solution of lactic acid.

Abstract: The techniques for processing lactic acid/lactate salt mixtures are provided. Preferred mixtures for processing are obtained from fermentation broths, preferably from fermentation processes conducted at a pH of 4.8 or lower. The techniques generally concern the provision of separated lactic acid and lactate streams, from the mixtures. Preferred techniques of separation and processing of each of the streams are provided.

Abstract: The invention relates to a method for the preparation of lactic acid and calcium sulphate, in which (a) an aqueous solution that contains lactate is reacted with sulphuric acid at a temperature that is essentially higher than the transition temperature of calcium sulphate dihydrate (CaSO4.2H2O), with the formation of a mixture that contains calcium sulphate hemihydrate and lactic acid, (b) the mixture from step (a) is subjected to at least one recrystallisation step at a temperature that is essentially lower than the transition temperature of calcium sulphate dihydrate, with the formation of a precipitate of calcium sulphate dihydrate and an aqueous solution of lactic acid, and (c) the precipitate of calcium sulphate dihydrate is separated off from the aqueous solution of lactic acid.

Abstract: A process for the solid-phase synthesis of salts of organic acids in a granular, free-flowing, and dust-free form particularly suited for use as animal feed additives. A liquid organic acid is applied to an inert, absorbent carrier. A solid base is then added during stirring. The acid is slowly released from the carrier preventing the fast reactions that lead to the formation of clumps. The exothermic reaction releases heat which assists in reducing the moisture content of the product.

Abstract: Disclosed herein are methods for the recovery of an organic acid, such as a heat stable lactic acid, from a feed stream comprising at least one of an organic acid amide, an organic acid ammonium salt, or an alkylamine-organic acid complex. The feed stream that comprises the organic acid amide, organic acid ammonium salt, or alkylamine-organic acid complex is mixed with at least one azeotroping agent. The azeotroping agent is a hydrocarbon capable of forming at least one azeotrope with the organic acid that is produced by the thermal decomposition of the amide, ammonium salt, or complex in the feed stream. Preferably the azeotrope is a heteroazeotrope. The mixture comprising the feed stream and the azeotroping agent is heated to produce a vapor stream that comprises the azeotrope. The vapor stream can be condensed to a liquid stream, and the organic acid is recovered in the liquid stream that is produced.

Abstract: Disclosed herein are methods for the recovery of at least one of an organic acid or an organic acid amide, such as a heat stable lactic acid or lactamide, from a feed stream comprising the organic acid and/or organic acid amide. The feed stream that comprises the organic acid and/or organic acid amide is mixed with at least one azeotroping agent. The azeotroping agent is a hydrocarbon capable of forming at least one heteroazeotrope with the organic acid or the organic acid amide. The mixture comprising the feed stream and the azeotroping agent is heated to produce a vapor stream that comprises the heteroazeotrope. The vapor stream can be heated further to separate components or it can be condensed into a liquid stream. The liquid stream is capable of being separated into a first phase and a second phase. The first phase contains the highest concentration of the organic acid and/or the organic acid amide and the second phase comprises the azeotroping agent.

Abstract: Disclosed is a process wherein a solution of a carboxylic acid in a first solvent and an alcohol are fed to a simulated moving bed reactor (SMBR) containing a solid(s) to produce a first stream comprising a solution of an ester of the carboxylic acid and the alcohol and a second stream comprising the first solvent. The solid(s) present in the SMBR facilitates the esterification reaction and the separation of the first solvent from the carboxylic acid. The process is particularly valuable for the preparation of an alkanol solution of an alkyl 2-keto-L-gulonate ester (AKLG) from an aqueous fermentation broth containing dissolved 2-keto-L-gulonic acid (KLG) by feeding the fermentation broth and an alkanol to a simulated moving bed reactor which contains a solid acidic esterification catalyst to produce a stream comprising an alkanol solution of an ALKG. The alkanol solution of an ALKG may be used directly to convert the ALKG to ascorbic acid (Vitamin C).

Abstract: The present disclosure provides a process for preparing a purified lactic acid solution suitable for use in connection with a source of lactate material a pH within the range of 0.8 to 9.0. The process includes the steps of providing a source of lactate material which includes a calcium salt; acidulating the concentrated broth with sulfuric acid to form an acidulated solution which includes lactic acid and calcium sulfate; reducing an amount of calcium sulfate from the acidulated solution; extracting the acidulated solution with an amine extractant to form a loaded solvent; and back extracting the loaded solvent with an aqueous solvent to provide a purified solution of lactic acid. Optionally, the source of lactate material can be concentrated prior to the step of acidulating. Alternately, the amine extractant can include sulfate anion. The sulfuric anion in the amine extractant can be residual sulfuric acid from the acidulation step.

Abstract: The invention concerns a method for recuperating and purifying a lactic acid solution obtained initially from a fermentation medium or any other source, consisting in a pre-treatment to eliminate the ion loads capable of catalysing the lactic acid condensation and based on the principle of ion exchange or any other related principle, followed by at least a step of concentration at low temperature and brief retention time and at least a step of distilling the lactic acid using a thin layer process.

Abstract: Cyclic esters of hydroxy organic acids can be produced and recovered via azeotropic distillation. In certain embodiments cyclic esters, such as glycolide and lactide, can be produced from a fermentation broth or other feed stream that comprises a hydroxy organic acid, an ammonium salt of a hydroxy organic acid, an amide of a hydroxy organic acid, or an ester of a hydroxy organic acid using azeotropic distillation. The hydroxy organic acid of the feed stream or the hydroxy organic acid derived from the feed stream by decomposition is reacted to produce the cyclic ester. In other embodiments a crude composition of a cyclic ester of an organic ester can be purified using azeotropic distillation.

Abstract: A process for the production and isolation of lactic acid is provided. A lactate feed solution, preferably obtained from a fermentation broth is combined with and extracted by a water-immiscible base in the presence of an acidifying agent. Lactic acid is recovered from the resulting organic phase. Recovered carbonate or bicarbonate from the aqueous phase can be recycled to the fermentor and regenerated extractant can be recycled for use in the extraction.

Abstract: The invention provides a process for producing lactic acid and products thereof from a medium containing an alkaline earth-metal salt of lactic acid, comprising (a) reacting a conjugated base of an alkali metal from a subsequent step with the medium to form a water soluble alkali metal lactate salt and a basic compound of the alkaline earth metal; (b) separating the water soluble alkali metal lactate salt and the basic compound of the alkaline earth metal; (c) splitting the water soluble alkali metal lactate to form a conjugated alkali metal base and a lactic acid product, which product is selected from the group consisting of lactic acid, a derivative thereof and combination thereof; (d) separating the conjugated alkali metal base and the lactic acid product; (e) reusing the separated conjugated alkali metal base or a product thereof in the step (a) and (f) reusing the basic compound of the alkaline earth metal separated in step (b), or a product thereof to form an alkaline earth-metal salt of lactic acid

Abstract: The invention provides a method for recovering low-boiling acids from a concentrated solution of the calcium salt of the acid by treating the concentrated solution of calcium salts of the low-boiling acids with a high molecular weight tertiary amine and carbon dioxide.

Abstract: The invention relates to a process for the preparation of high purity lactic acid from an aqueous solution containing said acid in the form of salt(s), characterised in that the aqueous solution is treated with a strong acid in order to liberate lactic acid in the free form and to produce salts of the corresponding strong acid, said salts of the strong acid are crystallised by evaporative crystallisation and lactic acid is recovered in the free form in solution.

Abstract: Polycarboxylic acids are purified by contacting a crude polycarboxylic acid with a solvent to produce a substantially pure polycarboxylic acid. The solvent is chosen so that the impurities are soluble in the solvent and the polycarboxylic acid is insoluble in the solvent.

Abstract: The techniques for processing lactic acid/lactate salt mixtures are provided. Preferred mixtures for processing are obtained from fermentation broths, preferably from fermentation processes conducted at a pH of 4.8 or lower. The techniques generally concern the provision of separated lactic acid and lactate streams, from the mixtures. Preferred techniques of separation and processing of each of the streams are provided.

Abstract: The invention relates to a process for the preparation of high purity lactic acid from an aqueous solution containing said acid in the form of salt(s), characterised in that the aqueous solution is treated with a strong acid in order to liberate lactic acid in the free form and to produce salts of the corresponding strong acid, said salts of the strong acid are crystallised by evaporative crystallisation and lactic acid is recovered in the free form in solution.

Abstract: The techniques for processing lactic acid/lactate salt mixtures are provided. Preferred mixtures for processing are obtained from fermentation broths, preferably from fermentation processes conducted at a pH of 4.8 or lower. The techniques generally concern the provision of separated lactic acid and lactate streams, from the mixtures. Preferred techniques of separation and processing of each of the streams are provided.

Abstract: Carboxylic acids are sorbed from aqueous feedstocks onto a solid adsorbent in the presence of carbon dioxide under pressure. The acids are freed from the sorbent phase by a suitable regeneration method, one of which is treating them with an organic alkylamine solution thus forming an alkylamine-carboxylic acid complex which thermally decomposes to the desired carboxylic acid and the alkylamine.

Abstract: A process is disclosed for producing an organic acid and optionally for simultaneously producing an ester of the organic acid.

Abstract: This invention provides a method for thermally converting volatile fatty acid (VFA) salts to ketones by mixing dry calcium salts of VFAs with hot heat transfer agent in an evacuated container, thereby causing thermal decomposition of the calcium salts of VFAs to form ketone-containing vapor and calcium carbonate; and separating the ketone-containing vapor from the calcium carbonate and heat transfer agent by condensing a mixture of ketones from the ketone-containing vapor. This invention also provides a process for conversion of VFA salts, produced by anaerobic fermentation of cellulosic biomass, into liquid fuels, volatile fatty acids, aldehydes, alcohols, and lactic acid.

Abstract: The techniques for processing lactic acid/lactate salt mixtures are provided. Preferred mixtures for processing are obtained from fermentation broths, preferably from fermentation processes conducted at a pH of 4.8 or lower. The techniques generally concern the provision of separated lactic acid and lactate streams, from the mixtures. Preferred techniques of separation and processing of each of the streams are provided.

Abstract: &agr;-Hydroxycarbonyl compounds are obtained from aldehydes or ketones by forming an acetal or ketal which is decomposed to a vinyl ether. The ether is selectively oxidized under conditions yielding an &agr;-hydroxy-aldehyde or &agr;-hydroxy-ketone with the carbonyl group protected. The last-mentioned compounds are valuable sources for other functional organic molecules, for example lactic acid.

Abstract: A process for the production and isolation of lactic acid is provided. A lactate feed solution, preferably obtained from a fermentation broth is combined with and extracted by a water-immiscible base in the presence of an acidifying agent. Lactic acid is recovered from the resulting organic phase. Recovered carbonate or bicarbonate from the aqueous phase can be recycled to the fermentor and regenerated extractant can be recycled for use in the extraction.

Abstract: The invention provides a process for the recovery of purified lactic acid values from an aqueous feed solution containing lactic acid, lactic acid salt, or mixtures thereof, comprising: bringing the feed solution into contact with a substantially immiscible anion exchanger to form a substantially water-immiscible phase comprising an anion exchanger-lactic acid adduct; effecting a condensation reaction in the substantially water-immiscible phase between a carboxylic moiety of the lactic acid adduct and a moiety selected from a hydroxyl moiety and a primary or secondary amine moiety to respectively form a lactic acid ester or amine product; and separating the formed lactic acid product from the anion exchanger.

Abstract: Described are preferred processes and apparatuses for thermally desorbing desired chemical products from resins to which they are adsorbed. The processes and apparatuses provide highly efficient use of applied heat throughout resin preheat, desorption and cooling phases.

Abstract: A process for treating pyruvic acid and other impurities of lactic acid by reduction treatment of an aqueous lactic acid solution and for obtaining high quality lactic acid having a substantially no pyruvic acid content, high purity, excellent heat stability and improved smell. Further, a high molecular weight polylactic acid having low coloration and consistent quality can be prepared by dehydration polycondensation of lactic acid obtained by the reduction treatment.

Abstract: A propene ether is selectively oxidized to an aldehyde-masked 2-hydroxypropanal using a metal-containing oxidation catalyst.

Abstract: A process for the production of lactic acid and for the separation and/or recovery of lactic acid from a lactate feed solution. A lactate feed solution preferably obtained from a fermentation broth is combined with and extracted by a water immiscible trialkyl amine in the presence of carbon dioxide. Lactic acid is recovered from the resulting organic phase. Recovered carbonate or bicarbonate from the aqueous phase is preferably recycled to the fermentor and regenerated extractant is preferably recycled for use in the extraction.

Abstract: A process for preparing .alpha.-hydroxy acids by heating ammonium salts of .alpha.-hydroxy acids of general formula (I), removing the formed ammonia and water, adding water to the residue, and heating the obtained mixture, wherein R is hydrogen, C.sub.1 -C.sub.6 alkyl, alkyl(C.sub.1 -C.sub.6)thioalkyl (C.sub.1 -C.sub.6), phenyl or the like. This process is freed from the problem of disposal of by-products such as ammonium bisulfate and makes it possible to prepare a free .alpha.-hydroxy acid from an ammonium salt thereof economically and in a high yield.

Abstract: A lactic acid based by-product formed in a process of producing a lactic acid based composition is subjected to racemization in the presence or absence of a catalyst to thereby obtain a lactic acid component having substantially optical inactivity. Then, lactide or polylactic acid having optical inactivity can be obtained from the lactic acid component having the optical inactivity. The obtained lactide or polylactic acid is mixed with lactide or polylactic acid having an optical purity in a range of 90 to 100% e.e. at a predetermined ratio to thereby obtain lactide or polylactic acid having a desired optical purity.

Abstract: This invention provides a method for thermally converting volatile fatty acid (VFA) salts to ketones by mixing dry calcium salts of VFAs with hot heat transfer agent in an evacuated container, thereby causing thermal decomposition of the calcium salts of VFAs to form ketone-containing vapor and calcium carbonate; and separating the ketone-containing vapor from the calcium carbonate and heat transfer agent by condensing a mixture of ketones from the ketone-containing vapor. This invention also provides a process for conversion of VFA salts, produced by anaerobic fermentation of cellulosic biomass, into liquid fuels, volatile fatty acids, aldehydes, alcohols, and lactic acid.

Abstract: A cation exchange membrane mediated acid-salt metathetic process. An aqueous salt solution is placed into a first compartment on one side of the membrane together with an organic amine extractant of limited water miscibility, and an aqueous acid solution is placed into a second compartment on the other side of the membrane. Product acid forms in the first compartment and collects in the organic amine extractant from where it is recovered. The process is particularly suitable for the recovery of a carboxylic acid from its salt.

Abstract: This invention provides a method for thermally converting volatile fatty acid (VFA) salts to ketones by mixing dry calcium salts of VFAs with hot heat transfer agent in an evacuated container, thereby causing thermal decomposition of the calcium salts of VFAs to form ketone-containing vapor and calcium carbonate; and separating the ketone-containing vapor from the calcium carbonate and heat transfer agent by condensing a mixture of ketones from the ketone-containing vapor.

Abstract: Carboxylic acids are sorbed from aqueous feedstocks onto a solid adsorbent. The acids are freed from the sorbent phase by treating it with an organic solution of alkylamine thus forming an alkylamine/carboxylic acid complex which is decomposed with improved efficiency to the desired carboxylic acid and the alkylamine. Carbon dioxide addition can be used to improve the adsorption or the carboxylic acids by the solid phase sorbent.

Abstract: The invention provides a process for the recovery of lactic acid from an aqueous liquor containing water and calcium lactate, comprising the extraction step of combining the lactate aqueous liquor with an extractant containing at least one water immiscible amine having a total of at least 18 carbon atoms in the presence of carbon dioxide to form an aqueous phase and an organic phase containing extracted lactic acid and the extractant and separating lactic acid from the organic phase, characterized in that a carbohydrate is added to the aqueous liquor, the carbohydrate being present in the aqueous liquor at a weight concentration of at least 10% of the water content thereof.

Abstract: A process for the production of lactic acid and for the separation and/or recovery of lactic acid from a lactate feed solution. A lactate feed solution preferably obtained from a fermentation broth is combined with and extracted by a water immiscible trialkyl amine in the presence of carbon dioxide. Lactic acid is recovered from the resulting organic phase. Recovered carbonate or bicarbonate from the aqueous phase is preferably recycled to the fermentor and regenerated extractant is preferably recycled for use in the extraction.

Abstract: A sample is treated with a phosphoglyceric acid mutase (PGAM) inhibitor (polythionic acid (salt) such as potassium tetrathionate) to inactivate the M-type isozyme activity and the B-type PGAM is quantified by determining PGAM isozymes by a rate assay. The B-type PGAM is a novel marker for cerebral apoplexy, and the diagnosis of cerebral apoplexy is enabled by assaying it.

Abstract: A process for the production of lactic acid and for the separation and/or recovery of lactic acid from a lactate feed solution. A lactate feed solution preferably obtained from a fermentation broth is combined with and extracted by a water immiscible trialkyl amine in the presence of carbon dioxide. Lactic acid is recovered from the resulting organic phase. Recovered carbonate or bicarbonate from the aqueous phase is preferably recycled to the fermentor and regenerated extractant is preferably recycled for use in the extraction.

Abstract: Recovery of carboxylic acid from an amine-based, water-immiscible organic extractant solution thereof that contains an enhancer, by extraction of the acid into an aqueous phase. A low molecular, at least partly water-miscible organic compound being a C.sub.2 -C.sub.5 alkanol, an acetate of a C.sub.1 -C.sub.3 alkanol and acetone is used as enhancer. In operation, the enhancer is recovered and recycled. The process is applicable, among others, to the recovery of carboxylic acid from a fermentation broth.

Abstract: A method is described for the determination of lactic acid in organic materials of alimentary interest that involves reacting, in a buffered aqueous medium, a sample of the said materials, or a solution obtained by extracting them, with an enzyme system comprising L(+) lactate oxidase, D(-) lactate dehydrogenase and horseradish peroxidase and measuring the concentration of any oxygen produced as a result of the oxidation of the lactic acid contained in the said sample with an amperometric electrode that is selective for oxygen.A biosensor that can be used to put the above method into effect is also described.

Abstract: The present invention relates to methods and apparatus for reducing the fouling of ion-selective membranes used in the electrodialytic purification of organic acids. More particularly, the present invention relates to the use of nanofiltration and chelating agents for removal of impurities from an organic acid-containing feed material to reduce the fouling of ion-selective membranes used in electrodialysis.

Abstract: The subject of the invention is a process for extracting pure lactic acid from fermentation liquors by ion exchange chromatography on a strongly acidic cation exchanger, preferably in H.sup.+ form. In a first step, the NH.sub.4 lactate coming from the fermentation is converted into the free acid by genuine ion exchange. This conversion is preferably effected on a weakly acidic cation exchanger in H.sup.+ form.

Abstract: A cosmetic composition comprising a hydroxy material selected from;a) layered double hydroxides of formula[M.sub.(1-a) N.sub.a (OH).sub.2 ].sup.y+ X.sup.x-.sub.y/x.zH.sub.2 O(I)b) a hydroxy salt of formula[M'(OH).sub.(2-a') ].sup.a'+ (X.sup.x-).sub.(a'-/x).zH.sub.

Abstract: An optically-active or chiral compound is described which comprises(A) at least one quaternary nitrogen or phosphorus cation provided that if the cation is a quaternary nitrogen cation containing a hydroxyalkyl group, the hydroxyalkyl group is free of chlorine, and(B) at least one optically-active anion.In one embodiment, the optically-active anion is an optically-active carboxylic acid anion. The process for preparing such optically-active compounds also is described and such compounds may be prepared by reacting(A) at least one quaternary nitrogen or phosphorus salt with(B) at least one optically-active reactant capable of reacting with the salt provided that if the salt is a quaternary nitrogen salt containing a hydroxyalkyl group, the hydroxyalkyl group is free of chlorine.

Abstract: Described is a process for recovering phytic acid or phytic acid salt from a medium in which it is contained. This process includes contacting the medium with a solid-phase free base polymer having tertiary amine functions to adsorb the phytic acid or salt thereof. In one preferred mode, the medium to be treated also contains lactic acid, and separate fractions predominant in (i) lactic acid and (ii) phytic acid or phytic acid salt, respectively, are recovered. Also described are preferred processes for treating mediums to recover lactic acid therefrom, and a favored process for obtaining inositol directly by hydrolyzing phytic acid or phytic acid salt while adsorbed on a pyridine-containing polymer.

Abstract: A test device for determining the presence of leukocyte cells, esterase or protease in a test sample is disclosed. The test device comprises a carrier matrix having a reagent composition incorporated therein, wherein the reagent composition comprises a lactate ester having the structure ##STR1## wherein A is an alcohol blocking group, and wherein B--O-- is a residue of compound B--OH and provides a detectable response when the lactate ester is hydrolyzed; and a buffer. In a preferred embodiment, the lactate ester has the structure ##STR2## wherein X is O, S or NR.sup.2, R is aryl or lower alkyl, R.sup.1 is hydrogen or lower alkyl, and R.sup.2 is hydrogen, lower alkyl or aryl.