Abstract: A method of reducing color in an alkanolamine, the method comprising: contacting the alkanolamine with an amount of an aqueous solution effective to provide 5 to 1000 parts per million by weight of an alkali metal borohydride, based on parts by weight of the alkanolamine; and 0.5 to 10,000 parts per million by weight of an alkali metal hydroxide, based on parts by weight of the alkanolamine; preferably wherein the color-reduced alkanolamine is not distilled after the contacting.

Abstract: A process for recovering an alkanolamine from a used gas scrubbing stream wherein a dynamic reaction system is employed to maximize conversion of bis-urea compounds typically formed in the gas scrubbing operation into the alkanolamine and minimize the formation of amino ethers which irreversibly convert the alkanolamine. A method of removing waste products from the system by the use of a wiped film evaporator.

Abstract: The present invention relates to separating one or more amine byproducts from one or more desired amines. More particularly, the invention involves forming a byproduct component with one or more amine byproducts and a first adjuvant component. The byproduct component has an enhanced separation characteristic relative to separating the amine byproducts from the desired amines in the absence of an adjuvant. Preferably, the byproduct component is separated in the presence of a second adjuvant component that preferably has a boiling point less than the boiling point of the first adjuvant component.

Abstract: The present invention provides methods that are used to decolorize compositions containing one or more amines in the presence of one or more weak acids. Significantly, the weak acids, particularly organic acids such as glacial acetic acid, when used in combination with a heat treatment produce dramatically less by-products than do the stronger mineral acids, making heat treatments and subsequent separation techniques more effective while producing less waste. In some modes of practice, the weak acids do not need to be neutralized, eliminating neutralizing steps and waste streams associated with neutralization. Low color products can be obtained easily at very high yield as a consequence.

Abstract: Method for purifying compounds (I) containing amino groups from a polar phase A, where (I) is converted by reaction with an aldehyde or ketone (II) into the corresponding imine (III) which is insoluble or sparingly soluble in the polar phase A, and then the imine (III) is converted to a nonpolar phase B and separated off from phase A, and then the compound containing amino groups is recovered from the imine (III).

Abstract: The present invention relates to a mixture of ethylenediamine (EDA) and N-methylethylenediamine (Me-EDA) with a low content of Me-EDA, which comprises at least 99.5% by weight of ethylenediamine, and wherein the concentration of N-methylethylenediamine is in the range from 0.005 to 0.15% by weight. The present invention further relates to a process for distillative workup of a mixture comprising EDA, Me-EDA and water, by introducing the mixture into a distillation column which is operated at a column top pressure of 10 mbar to 4 bar, wherein the weight ratio of water to ethylenediamine in the mixture used is a*X:Y where X is the proportion by weight of water and Y is the proportion by weight of ethylenediamine at the azeotropic point of a binary mixture of water and ethylenediamine at the column top pressure in question, and a is a real number with a value of 0.9 or more.

Abstract: The present invention describes a method to recover organic tertiary amines from waste sulfuric acid comprising the following steps: a) reacting i) waste sulfuric acid comprising organic tertiary amines with ii) ammonia in an amount sufficient to obtain a pH of 9.5 or higher and b) separating the organic tertiary amines from the reaction mixture obtained in step a) wherein during the separation the pH of the reaction mixture is adjusted at a pH of 9.5 or higher.

Abstract: The present invention relates to a process to prepare ethylene amines by the amination of ethylene oxide, ethylene glycol or ethanolamine in the presence of a catalyst, comprising a step wherein methylamine and/or ethylamine are removed from the reaction effluents.

Abstract: The present invention relates to separating one or more amine byproducts from one or more desired amines. More particularly, the invention involves forming a byproduct component with one or more amine byproducts and a first adjuvant component. The byproduct component has an enhanced separation characteristic relative to separating the amine byproducts from the desired amines in the absence of an adjuvant. Preferably, the byproduct component is separated in the presence of a second adjuvant component that preferably has a boiling point less than the boiling point of the first adjuvant component.

Abstract: The present invention provides methods that are used to decolorize compositions containing one or more amines in the presence of one or more weak acids. Significantly, the weak acids, particularly organic acids such as glacial acetic acid, when used in combination with a heat treatment produce dramatically less by-products than do the stronger mineral acids, making heat treatments and subsequent separation techniques more effective while producing less waste. In some modes of practice, the weak acids do not need to be neutralized, eliminating neutralizing steps and waste streams associated with neutralization. Low color products can be obtained easily at very high yield as a consequence.

Abstract: Impure hexamethylenediamines and more particularly those hexamethylenediamines containing contaminating amounts of tetrahydroazepine (THA), or more generally contaminating amounts of imines, are purified by distillation carried out with a short retention time of the impure hexamethylenediamine in the distillation column; the hexamethylenediamine obtained has a very low concentration of THA.

Abstract: A method for producing a diamine includes purifying a diamine from an aqueous solution containing a diamine salt by adding an alkaline substance to the aqueous solution and then filtering the resulting solution by allowing the solution to pass through a nanofiltration membrane to remove the salt, thereby obtaining an aqueous diamine solution.

Abstract: The present invention relates to the use of recombinant microorganisms comprising DNA molecules in a deregulated form which improve the production of cadaverine, as well as to recombinant DNA molecules and polypeptides used to produce the microorganism, said microorganism comprising an intracellular lysine decarboxylase activity and an enhanced lysine import activity or comprising an intracellular and an extracellular lysine decarboxylase activity or comprising an intracellular and extracellular lysine decarboxylase activity and an enhanced lysine import activity. The present invention also relates to a processes for the production of cadaverine using recombinant microorganisms.

Abstract: A process for the separation of a first amine having a tertiary amine group and a secondary amine group such as N,N,N?-trimethylbis(aminoethyl)ether from a di-tertiary amine such as N,N,N?,N?-tetramethylbis(aminoethyl)ether, comprising: contacting a mixture of the first amine and the di-tertiary amine with a carbonyl compound capable of forming an enamine such that the carbonyl compound reacts with the first amine to form an enamine; separating the enamine from the di-tertiary amine; and subsequently converting the enamine to the first amine.

Abstract: This invention provides chain extender compositions. These compositions comprise (i) an aliphatic secondary diamine, and (ii) a component selected from the group consisting of: (a) a cycloaliphatic primary diamine; (b) an aliphatic secondary diamine; (c) an aliphatic secondary diamine and an aliphatic primary diamine; (d) an aliphatic diimine; and (e) a combination of any two or more of (a) through (d), with the proviso that when (ii) is (a), (i) is a noncyclic aliphatic secondary diamine. Processes for producing polyurethanes, polyureas, and polyurea-urethanes are also provided.

Abstract: In a process for the accelerated reduction of organic substrates, selected from the group consisting of esters, amides, nitriles, acids, ketones, imines or mixtures thereof, they are reacted with an amine borane, sulfide borane or ether borane complex as a borane source in the presence of organic accelerator compounds containing either Lewis acidic or Lewis basic sites in their structure, of which the Lewis acidic site can coordinate with the carbonyl or nitrile or imine group of the substrate or the Lewis basic site can coordinate with the borane.

Abstract: The invention relates to a process for the isolation of an organic amine from a composition comprising the organic amine and an acid, or a salt of the organic amine and the acid, wherein the process comprises steps wherein ammonia or hydrazine is added to the composition thereby forming a multi-phase system comprising an organic amine-rich phase and an acid-rich phase, the organic amine-rich phase and the acid-rich phase obtained in step (i) are separated, and the organic amine is isolated from the organic amine-rich phase.

Abstract: Primary diamines are prepared by hydrogenation of a dinitrile compound in the presence of a catalyst, in particular hexamethylenediamine is prepared by hydrogenation of adiponitrile; the product diamines are recovered by distillation in several distillation columns mounted in series and the heavy impurities are separated from the second distillation.

Abstract: The present invention relates to linear amine-functionalized poly(trimethylene ether) compositions, and processes to produce these compositions.

Abstract: Impure hexamethylenediamines and more particularly those hexamethylenediamines containing contaminating amounts of tetrahydroazepine (THA), or more generally contaminating amounts of imines, are purified by distillation carried out with a short retention time of the impure hexamethylenediamine in the distillation column; the hexamethylenediamine obtained has a very low concentration of THA.

Abstract: An epichlorohydrinamine polymer has a ratio of amine units to epichlorohydrin units of from 0.8:1.2 to 1.0:1.0, dimethylaminopropylamine and benzylamine preferably being used as amine and/or ammonium units. The novel epichlorohydrinamine polymer is used, for example, for the surface treatment of semifinished leather products and textile materials.

Abstract: In a neutralization and recovery process ethylene diamine hydrochloride (EDA-HCL) is neutralized and ethylene diamine (EDA) is recovered using a mixture of solid caustic dissolved in a non-aqueous solvent, for example an alcohol.

Abstract: Polyols or polyisocyanates, or both, are treated to reduce aldehyde impurities before being reacted together to form a polyurethane. Polyols are treated by adding certain aminoalcohols to them, preferably in the presence of a tertiary amine catalyst. Polyisocyanates are treated by added certain nitroalkanes to them, also preferably in the presence of a tertiary amine catalyst. Polyurethanes made using the treated materials emit smaller quantities of aldehydes.

Abstract: Method of producing triethanolamine where a phosphane or a compound which liberates a phosphane is added to the triethanolamine.

Abstract: In a process for the accelerated reduction of organic substrates, selected from the group consisting of esters, amides, nitriles, acids, ketones, imines or mixtures thereof, they are reacted with an amine borane, sulfide borane or ether borane complex as a borane source in the presence of organic accelerator compounds containing either Lewis acidic or Lewis basic sites in their structure, of which the Lewis acidic site can coordinate with the carbonyl or nitrile or imine group of the substrate or the Lewis basic site can coordinate with the borane.

Abstract: The invention relates to the field of separation by distillation of 6-aminocapronitrile (ACN) and hexamethylenediamine (HMD) from a mixture containing ACN, HMD, tetrahydrozaepine (THA), adiponitrile (ADN) and low boilers (LB). A method for producing a distillate stream comprising HMD is disclosed, which is suitable for the production of Nylon-6,6. The tails stream from the distillation of the mixture can be further distilled to produce a distillate containing ACN and THA, which is particularly suitable for use in the production of caprolactam and Nylon-6 from the caprolactam. Process conditions of the method of the invention disfavor the production of 2-cyanocyclopentylideneirnine (CPI).

Abstract: A process for reducing the level of an aliphatic monounsaturated amine (IV) in a mixture (V) containing an aminonitrile (I) or a diamine (II) or a dinitrile (III) or mixtures thereof as well as said mine (IV) by a) reacting said mixture (V) with an anionic nucleophile (VI) which contains a nucleophilic atom selected from the group consisting of oxygen, nitrogen and sulfur, which is capable of taking up an H+ ion to form an acid having a pKa value in the range from 7 to 11, as measured in water at 25° C., and which has a relative nucleophilicity, as measured in methyl perchlorate/methanol at 25° C., in the range from 3.4 to 4.7 when said nucleophilic atom is oxygen, in the range from 4.5 to 5.8 when said nucleophilic atom is nitrogen, and in the range from 5.5 to 6.8 when said nucleophilic atom is sulfur, in an amount in the range from 0.01 to 10 mol per mole of said amine (IV) in said mixture (V) at a temperature in the range from 50 to 200° C.

Abstract: The invention relates to a process for continuously, distillatively removing piperazine from an ethylenediamine-piperazine mixture under pressure at elevated temperature, by discharging the ethylenediamine at the top and the piperazine at the bottom of a distillation column. For the purpose of improving the quality of the piperazine, especially its color and color stability, the piperazine is subjected directly to circulation conveying it through an evaporator unit operated at a temperature of from about 160° C. to about 170° C. and returning it into the distillation column. After a residence time of from about 30 min to about 60 min in the circulation system, the piperazine is discharged in vapor form from a side draw in the lower section of the distillation column.

Abstract: The invention relates to the field of separation by distillation of 6-aminocapronitrile (ACN) and hexamethylenediamine (HMD) from a mixture comprising ACN, HMD, tetrahydroazepine (THA), adiponitrile (ADN) and low boilers (LB). Also disclosed is a method for producing a distillate stream comprising HMD; a side draw stream comprising ACN, THA and low levels of dimers of ACN and HMD; and a tails stream comprising ACN, THA and substantially higher levels of dimers of ACN and HMD than found in the side draw stream. The side draw stream is particularly suitable for use in the production of caprolactam since the low levels of dimers of ACN and HMD do not greatly affect the catalyst life in the caprolactam production process. The tails stream can be further distilled to produce a tails distillate stream comprising ACN and THA, which can be recycled back to the first distillation column, further increasing recovery of ACN from the feed stream.

Abstract: A process is provided for reducing the content of a monounsaturated aliphatic amine (III) in a mixture (IV) containing an aminonitrile (I) or a diamine (II), or mixtures thereof, and the amine (III), wherein a) the mixture (IV) is reacted with an anionic nucleophile (V),  which contains a nucleophilic atom selected from the group comprising oxygen, nitrogen and sulfur,  which is capable of taking up an H+ ion to form an acid with a pKa ranging from 7 to 11, measured in water at 25° C., and  which has a relative nucleophilicity, measured in methyl perchlorate/methanol at 25° C.,  ranging from 3.4 to 4.7 when oxygen is the nucleophilic atom,  ranging from 4.5 to 5.8 when nitrogen is the nucleophilic atom, and  ranging from 5.5 to 6.8 when sulfur is the nucleophilic atom,  in an amount ranging from 0.

Abstract: In a decarbonation process for removing carbon dioxide from a carbon dioxide-containing gas with the use of an amine compound-containing absorbing solution, an amine compound accompanying a decarbonated exhaust gas is efficiently recovered in the following manner: A water washing section is constituted in two stages, a first-stage water washing section 64 and a second-stage water washing section 65. In these water washing sections, recovery of the amine compound accompanying the decarbonated exhaust gas is performed sequentially. Regeneration tower refluxed water is supplied as washing water to the second-stage water washing section 65. Washing water is withdrawn from the second-stage water washing section 65 and supplied to the first-stage water washing section 64. Demisters 83, 84 and 85 are provided at outlets of a carbon dioxide absorption section 73, the first-stage water washing section 64 and the second-stage water washing section 65.

Abstract: High-purity alkanolamines, whose iron content is less than 50 ppb, are provided. Said high-purity alkanolamines can be produced by covering with an alkanolamine-resistant material at least a part of the inner wall of equipment that contacts alkanolamines from the top of the distillation tower to the storage tank in producing a high-purity alkanolamine from a crude alkanolamine by using distillation towers.

Abstract: In a decarbonation process for removing carbon dioxide from a carbon dioxide-containing gas with the use of an amine compound-containing absorbing solution, an amine compound accompanying a decarbonated exhaust gas is efficiently recovered in the following manner: A water washing section is constituted in two stages, a first-stage water washing section 64 and a second-stage water washing section 65. In these water washing sections, recovery of the amine compound accompanying the decarbonated exhaust gas is performed sequentially. Regeneration tower refluxed water is supplied as washing water to the second-stage water washing section 65. Washing water is withdrawn from the second-stage water washing section 65 and supplied to the first-stage water washing section 64. Demisters 83, 84 and 85 are provided at outlets of a carbon dioxide absorption section 73, the first-stage water washing section 64 and the second-stage water washing section 65.

Abstract: A method of recovering a decomposition product from a polyurethane, the method comprising the steps of thermally decomposing a polyurethane into a liquid containing a polyol and a urea compound which is soluble in the polyol, and solids containing a urea compound which is insoluble in the liquid in the presence of a polyamine compound at a temperature of 120 to 250° C.; removing the solids; hydrolyzing the residue with water retained at a high temperature of 200 to 320° C. and a high pressure; and recovering the resulting polyamine and/or polyol.

Abstract: The present invention provides a method of recovering a polyamine compound and/or a polyol compound useful for starting materials of polyurethane resin in an industrially advantageous manner by first dissolving the polyurethane resin such as polyurethane foams discharged in a large amount as industrial wastes in a solubilizing agent containing a polyamine compound, a low molecular glycol or an amino alcohol, hydrolyzing the resulting solution with liquid water at 200 to 320° C., then recovering the polyamino compound and/or polyol compound thus formed.

Abstract: High-purity alkanolamines, whose iron content is less than 50 ppb, are provided. Said high-purity alkanolamines can be produced by covering with an alkanolamine-resistant material at least a part of the inner wall of equipment that contacts alkanolamines from the top of the distillation tower to the storage tank in producing a high-purity alkanolamine from a crude alkanolamine by using distillation towers.

Abstract: The present invention provides a method of recovering a polyamine compound and/or a polyol compound useful for starting materials of polyurethane resin in an industrially advantageous manner by first dissolving the polyurethane resin such as polyurethane foams discharged in a large amount as industrial wastes in a solubilizing agent containing a polyamine compound, a low molecular glycol or an amino alcohol, hydrolyzing the resulting solution with liquid water at 200 to 320° C., then recovering the polyamino compound and/or polyol compound thus formed.

Abstract: A process for purifying alkenyl compounds having a divalent or trivalent heteroatom in the &agr;-position relative to the double bond by distillation comprises carrying out at least two distillations in which the purified alkenyl compounds are obtained from the gas phase by condensation, where the time between the first distillation after the synthesis of the alkenyl compounds and at least one further distillation is at least one day and the purified alkenyl compounds have an APHA color number of <30.

Abstract: The level of an unsaturated cyclic imine (I) of the formula (I) where R1 is alkenyl having 3, 4, 5, 6, 7, 8, 9, 10, 11 carbon atoms belonging to the ring system, in a mixture comprising hexamethylenediamine and an imine (I) is reduced by electrochemical conversion of an imine (I) in a mixture comprising hexamethylenediamine and an imine (I) in the presence of solvated protons into a saturated cyclic amine of the formula (II)

Abstract: A process for making HMD in which a butadiene hydrocyantion reaction product that contains phosphorous-containing impurities is treated with ozone.

Abstract: Preparation of alkanolamines having improved color quality by treating the alkanolamine with an effective amount of phosphorous acid or hypophosphorous acid or compounds thereof initially at elevated temperature over a period of at least 5 min (step a), and then distilling it in the presence of an effective amount of one of these phosphorus compounds (step b).

Abstract: Preparation of alkanolamines having improved color quality by treating the alkanolamine with hydrogen in the presence of a hydrogenation catalyst at elevated temperature, by using, as hydrogenation catalyst, a heterogeneous catalyst comprising Re, Ru, Rh, Pd, Os, Ir, Pt and/or Ag and a support material chosen from the group consisting of activated carbon, alpha-aluminum oxide, zirconium dioxide and titanium dioxide, where the catalyst, in the case of activated carbon as support material, has a cutting hardness of at least 10 N, a side crushing strength of at least 30 N or a compressive strength of at least 25 N.

Abstract: A method for separating a mixture of hexamethylenediamine, aminocapronitile and polarographically reducible impurities using fractional distillation in which the temperature in the rectifying zone of a distillation column varies sigmoidally along its length to force a major portion of the PRI to co-distill with the aminocapronitrile.

Abstract: Halides are removed from halide-containing nitrile mixtures by(a) thermally treating the halide-containing nitrile mixture,(b) subsequently adding a base to the thermally treated nitrile mixture and(c) subsequently separating off the base from the nitrile mixture.Amines are prepared by(A) reacting alkyl halides with metal cyanides in an at least two-phase reaction medium in the presence of halide-containing phase-transfer catalysts to give alkanenitriles,(B) separating off the resulting halide-containing alkanenitrile mixture phase and(C) further treating the halide-containing alkanenitrile mixture phase, as described in the stages(a)-(c) removing halides from halide-containing nitrile mixtures and(d) hydrogenating nitrites obtained in stage (c) to give amines, in the presence of suspended or fixed-bed catalysts.

Abstract: A process for recovering hexamethylenediamine (I) from a mixture (II) including(I) hexamethylenediamine,(III) hexamethyleneimine,(IV) a compound selected from 2-aminomethylcyclopentylamine and 1,2-diaminocyclohexane,(V) an imine,(VI) adiponitrile and 6-aminocapronitrileincludes distilling(a) a mixture (II) to obtain(a1) a low boiling fraction (III),(a2) a medium boiling fraction (VII) (I), (IV) and (V), and(a3) a high boiling fraction (V) and (VI),(b) a mixture (VII) to obtain(b1) an overhead product (IV), and(b2) a mixture (VIII) (I) and (V) as bottom product, and(c) a mixture (VIII) to obtain(c1) (I) as overhead product, and(c2) a bottom product (V).

Abstract: A process for removing tetrahydroazepine from aminocapronitrile or hexamethylenediamine by sequential distillation in which the overhead from the second distillation is combined with a fresh, incoming mixture of tetrahydroazepine and aminocapronitrile or hexamethylenediamine.

Abstract: The invention provides a method of industrially producing high-quality polyethylenepolyamines, which exerts high decolorizing effect and is economical, comprising the steps that hydrogen halide is added to a mixture of polyethylenepolyamines and heated, then distillation is performed to fractionate components each having a boiling point not higher than that of triethylenetetramine, next alkali metal hydroxide is added to that residual liquor after distillation to neutralize, and distillation is performed again to fractionate components each having a boiling point not lower than that of tetraethylenepentamine.

Abstract: Color-containing alkanolamines or alkyleneamines, having color numbers of up to 100 PtCo or higher, can be treated with polymeric solid acidic catalysts at elevated temperatures. Perfluorinated ion-exchange polymers in the acid form may be used as the polymeric solid acidic catalyst. In the presence of added water, these polymeric solid acidic catalysts produce decolorized alkanolamines or alkyleneamines having color numbers of 20 PtCo or less. The process of decolorization can be carried out in batch or continuous mode processes thus providing low cost, high quality and high purity end products.

Abstract: A process for the purification of tertiary amines in a crude mixture contaminated with undesirable primary and secondary amines which may have only a slight variance in boiling point with respect to the tertiary amine, wherein the crude mixture of the tertiary amine is treated at temperatures which may range from 0.degree. to 200.degree. C. but preferably from 20 to 150.degree. C. and at pressures of from 1 to 200 bar but most preferably under atmospheric pressure with a carboxylate of the formula ##STR1## in which R.sup.4 and R.sup.5 are selected from the group consisting of C.sub.1 -C.sub.20 -alkyl, C.sub.3 -C.sub.12 -cycloalkyl, C.sub.4 -C.sub.20 -cycloalkylalkyl, and aryl or C.sub.7 -C.sub.20 -aralkyl, both optionally mono- to penta- substituted by C.sub.1 -C.sub.8 -alkyl, C.sub.3 -C.sub.8 -cycloalkyl, or C.sub.4 -C.sub.12 -cycloalkylalkyl, and R.sup.

Abstract: A process for recovering monomer from multi-component waste material that includes a hydrolyzable polymer, the process including contacting the multi-component waste material with water and subjecting the resulting mixture to heat and pressure to form a liquid aqueous portion which mainly includes depolymerization products of the hydrolyzable polymer and a water insoluble portion which mainly includes components other than the depolymerization products; separating the liquid aqueous portion and the water insoluble portion; subjecting the separated aqueous portion to a pressure that is lower than that of step (a) and heat to produce a residue and a distillate which contains monomer; and separating the monomer in the distillate from other components in the distillate. The process is particularly useful for recovering caprolactam from waste materials that include nylon 6.