Abstract: The present invention concerns a process for providing tertiary amine products which are color-stable, and have a greatly reduced tendency to take on color during their storage. According to the invention, an ethyleneamine derivative is added to the distillation pot prior to or during the distillation of the tertiary amine product. Preferably, the ethyleneamine derivative has a higher boiling point than the desired tertiary amine product so as to preclude the ethyleneamine from distilling over with the tertiary amine.

Abstract: A process for producing a high purity trialkanolamine excelling in hue and having an APHA of not more than 40, characterizing by including producing a mixed alkanolamine by the reaction of an alkylene oxide with ammonia; removing low-boiling substances from the mixed alkanolamine; removing high-boiling substances by subjecting the product deprived of the low-boiling substance to vacuum distillation, and redistilling the distillate obtained by the vacuum distillation.

Abstract: The invention relates to a method for separating by distillation a portion or the entirety of an azeptine derivative (III), which is selected from the group consisting of aminohexylidene imine, tetrahydroazepine, hexylhexahydroazepine and of aminohexylhexahydroazepine, out of a mixture (II) containing an azepine derivative (III) and an amine (I). The inventive method is characterized in that the distillation is carried out with a maximum bottom temperature of 150° C.

Abstract: The invention relates to a method for producing a highly pure, aqueous hydroxylamine solution by distilling an aqueous solution, devoid of salt, of a hydroxyl ammonium salt in a plate column comprising at least two mechanical plates. Said method is characterised in that packing bodies are arranged between at least two plates of the plate column over the cross-section of said column.

Abstract: An amine-containing mixture containing one or more amines, water, low-boilers and optionally high-boilers is fractionated by a process having the steps (iii) and (iv) and optionally the steps (i), (ii) and (v): (i) a (first) low-boiler fraction is separated off from the amine-containing mixture by distillation, (ii) a (first) high-boiler fraction is separated off from the amine-containing mixture by distillation, (iii) the amine-containing mixture is extracted with sodium hydroxide solution, producing an aqueous, sodium-hydroxide-containing first phase and an aqueous-organic, amine-, (further) low-boiler- and possibly (further) high-boiler-containing second phase, (iv) the aqueous-organic second phase, is distilled, producing essentially anhydrous amine as bottom-phase take off or sidestream takeoff in the stripping part of the distillation column, an amine/water azeotrop as sidestream takeoff in the enrichment part of the column and a (further) low-boiler fraction as overhead takeoff, and recycling the amin

Abstract: A method for regenerating an amine extractant used for recovery of metals involves contacting a liquid organic phase containing an amine complexed with one or more metals with an aqueous solution substantially free of chloride ions to strip the one or more metals from the organic phase. The stripped organic phase is then contacted with a solution of hydrochloric acid to regenerate the amine extractant which can then be recycled in a production process.

Abstract: A mixture containing one or more amines, water, low-boilers and high-boilers, is fractioned in a process wherein (i) low-boilers are separated from the mixture by distillation, (ii) high-boilers are separated from the mixture by distillation, (iii) the mixture is extracted with a sodium hydroxide solution to form an aqueous, sodium-hydroxide-containing first phase and an aqueous-organic, amine-containing second phase, and (iv) the aqueous-organic second phase is distilled to form an amine/water azeotrop and an essentially anhydrous amine, and the amine/water azeotrop is recycled to the extraction step (iii).

Abstract: A method for recovering hexamethylene diamine (HMD) from a mixture comprising HMD, 6-aminocapronitrile (ACN) tetrahydroazepine (THA), and adiponitrile (ADN) is disclosed. The method includes introducing the mixture into a first distillation column, separating as a group the HMD, ACN and at least a portion of the THA as distillate from the ADN. The first distillation column is operated at a temperature and pressure to minimize isomerization of the ADN into 2-cyanocyclopentylideneimine(CPI). The distillate of the first distillation column is introduced into a subsequent distillation column and the HMD is separated from the ACN and THA.

Abstract: A process for producing an alkanolamine includes supplying a reactive distillation apparatus having an inner contacting surface which simultaneously facilitates a reaction process and a distillation process, feeding a first reactant including an amine represented by R?3-XNHX, wherein R? is a hydrocarbon group, and X is 1, 2, or 3, feeding a second reactant including an akylene oxide represented by R?O, wherein R? is a C2-C10-alkylene, feeding a catalyst in an amount from 0% to about 15% by weight of a mixture of the first reactant, the second reactant and the catalyst; recycling an overhead output from an overhead portion including an unreacted portion of the amine and the catalyst to achieve a substantially total reflux of the amine and the catalyst, and collecting a product output including an alkanolamine, the alkanolamine being a member selected from the group consisting of a monoalkanolamine, a dialkanolamine, and a trialkanolamine.

Abstract: A mixture containing mixture one or more amines, water, low-boilers and high-boilers, is fractioned in a process wherein (i) low-boilers are separated from the mixture by distillation, (ii) high-boilers are separated from the mixture by distillation, (iii) the mixture is extracted with a sodium hydroxide solution to form an aqueous, sodium-hydroxide-containing first phase and an aqueous-organic, amine-containing second phase, and (iv) the aqueous-organic second phase is distilled to form an amine/water azeotrope and an essentially anhydrous amine, and the amine/water azeotrope is recycled to the extraction step (iii).

Abstract: Process for extracting aqueous ketazine solutions which is carried out using an aqueous ketazine solution having a salt content of 5 to 27% by weight and an ammonia content of 0 to 28% by weight to extract at temperatures of 50 to 120° C., which is characterized in that the ketazine solution to be extracted has a molar excess of 50 to 200% of ketone based on the ketazine to be extracted, and that an aliphatic hydrocarbon extractant is used which has a boiling point of 150 to 300° C. at atmospheric pressure.

Abstract: A method for recovering hexamethylene diamine (HMD) from a mixture comprising HMD, 6-aminocapronitrile (ACN) tetrahydroazepine (THA), and ADN comprising:

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 removing hexafluoropropylene dimers (“HFP dimers”), dimer hydrides and other oligomers from a fluid is described. The method comprises heating the fluid to isomerize the HFP dimers to the thermodynamic isomer, and contacting the fluid with a tertiary amine (or salts thereof) to form a hexafluoropropylene dimer—tertiary amine adduct. The method may further comprise the step of separating the dimer adducts from the reaction mixture.

Abstract: This invention relates to an improvement in a process for effecting decolorization of an alkanolamine by subjecting the alkanolamine to hydrogenation in the presence of a hydrogenation catalyst. The improvement for removing color, by-products, or both from a dialkylalkanolamine represented by the formula: wherein R and R1 are methyl, ethyl, or a mixture thereof, which comprises: utilizing a catalyst comprised of palladium carried on gamma alumina as the hydrogenation catalyst.

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: The present invention relates to a continuous process for the manufacture of triethanolamine (TEA) comprising, in succession: (i) a step of synthesizing the TEA by continuously bringing ammonia into contact with ethylene oxide under conditions allowing the formation of a reaction mixture comprising mono-, di- and triethanolamines, (ii) a step of continuously separating the ammonia that has not reacted from the reaction mixture and (iii) a step of continuously separating the TEA from the mixture resulting from step (ii). The process is characterized in that a specific mixture of alkanolamines, comprising TEA and from 0.5 to 50% by weight of at least one secondary dialkanolamine, is prepared or isolated from the mixture resulting from step (ii), and in that the TEA is separated and isolated with a degree of purity equal to or greater than 99.2% by weight, by a continuous distillation of the specific mixture of alkanolamines.

Abstract: The present invention concerns a process for providing tertiary amine products which are color-stable, and have a greatly reduced tendency to take on color during their storage. According to the invention, an ethyleneamine derivative is added to the distillation pot prior to or during the distillation of the tertiary amine product. Preferably, the ethyleneamine derivative has a higher boiling point than the desired tertiary amine product so as to preclude the ethyleneamine from distilling over with the tertiary amine.

Abstract: Process for the recovery of a purified adiponitrile (ADN) from a mixture of adiponitrile, aminocapronitrile and hexamethylenediamine, utilizing two sequential distillations: (1) a first distillation in which the mixture is distilled in a distillation column at a head pressure that causes at least 7% of the ADN to go into the distillate, along with bishexamethylenetriamine (BHMT) and 2-cyanocyclopentylideneimine (CPI), and (2) a second distillation in which the distillate from the first distillation is distilled in a second distillation column at a head pressure sufficient to cause minimum-temperature azeotropy between ADN and BHMT, thereby allowing the majority of the BHMT and CPI to be removed from the second distillation as distillate, and ADN, substantially free of both BHMT and CPI, to be removed as bottoms.

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: 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: A method of decomposing wastes containing target compounds having one or more of hydrolyzable bonds of ether bond, ester bond, amide bond and isocyanate bond wherein the method comprises continuously supplying the wastes in a molten state or liquid state to a reactor, continuously supplying super-critical water or high pressure/high temperature water to the reactor, bringing the water into contact with the wastes, thereby decomposing the target compounds and then recovering them as raw material compounds or derivatives thereof for the target compounds. Target compounds contained in wastes in chemical plants which could not be utilized but merely incinerated or discarded so far are continuously decomposed into raw material compounds or derivatives thereof for the aimed compound and can be reutilized effectively.

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: 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 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 the removal of primary and secondary amine and alkanolamine impurities from aqueous tertiary amine and alkanolamine solutions without affecting the tertiary amine and/or alkanolamine by treating these solutions with a monoaldehyde or dialdehyde has been described.

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 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 of decomposing wastes containing target compounds having one or more of hydrolyzable bonds of ether bond, ester bond, amide bond and isocyanate bond wherein the method comprises continuously supplying the wastes in a molten state or liquid state to a reactor, continuously supplying super-critical water or high pressure/high temperature water to the reactor, bringing the water into contact with the wastes, thereby decomposing the target compounds and then recovering them as raw material compounds or derivatives thereof for the target compounds. Target compounds contained in wastes in chemical plants which could not be utilized but merely incinerated or discarded so far are continuously decomposed into raw material compounds or derivatives thereof for the aimed compound and can be reutilized effectively.

Abstract: A very pure aqueous solution of free hydroxylamine is prepared by a process in which the dilute, aqueous hydroxylamine solution is concentrated in a column by removing hydroxylamine-containing vapors via a side take-off in the bottom of the column, and very pure hydroxylamine is obtained by condensing the vapors. The novel process can be carried out simply, in a gentle manner and on a large scale and gives electronic grade hydroxylamine.

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: The present invention provides a process for easily producing an alkylene oxide adduct to an aliphatic amine compound which has a fully excellent color, is not turbid, and does not deteriorate in color even through long-term storage. That is, the present invention provides a process for producing an alkylene oxide adduct to a primary or secondary amine compound having an aliphatic, saturated or unsaturated, hydrocarbon radical having 8 to 22 carbon atoms, having an excellent color, by reacting an alkyene oxide to the amine compound, characterized by comprising the step of adding a base or an aqueous solution thereof to the amine compound and then heating the mixture.

Abstract: A process for the preparation of 3-amino-1,2-propanediol, commonly known as isoserinol, having an organic impurities content lower than 0.1% and an inorganic impurities content lower than 0.05%.

Abstract: A process for recovery of aminoalcohols from aqueous solutions containing inorganic salts is disclosed. The aqueous solution which contains aminoalcohols is then mixed with a base in order to increase the ph and the solution is then extracted with an alkyphenol solvent.

Abstract: The present invention provides a process for producing a tertiary aliphatic amine having high quality having little non-amines such as esters and alcohols, which is less colored, and which can be converted into a derivative without turbidity.That is, the present invention provides the process which comprises the steps of adding at least one alkali substance of potassium hydroxide and sodium hydroxide or an aqueous solution thereof to the crude tertiary amine product mixture and distilling the mixture to obtain the tertiary amine having a high quality.In addition, the tertiary amine has the formula: R.sub.1 R.sub.2 N--R.sub.3, wherein R.sub.1 and R.sub.2 being a saturated or unsaturated hydrocarbon having 6 to 28 carbon atoms, R.sub.3 being a saturated or unsaturated hydrocarbon having 1 to 5 carbon atoms.

Abstract: The instant invention is directed to a method for recovering surface active amines from an emulsion comprising the salt of the amine comprising (a) contacting an emulsion layer or phase containing surface active amine salt with an acid selected from the group comprising mineral acids and carbon dioxide in an amount sufficient and under conditions to produce an amine salt of said mineral acid or an amine bicarbonate, wherein said surface active amine salt is produced via emulsion fractionation with said surface active amine (b) separating an upper layer and a lower aqueous layer; (c) adding, to the lower aqueous layer, an inorganic base if step (a) utilizes a mineral acid, or heating at a temperature and for a time sufficient if step (a) utilizes carbon dioxide, to raise the pH of the aqueous layer to greater than or equal to 8; (d) blowing gas through said aqueous layer to produce a foam containing said surface active amine; (e) recovering said foam containing said surface active amine.

Abstract: A process is disclosed for the neutralization of amine or alkanolamine heat stable salts with aqueous KOH or with alkali metal base, such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate or potassium bicarbonate formulated with amines or alkanolamines. The process results in less solid formation than commonly used alkali metal bases such as aqueous sodium hydroxide or aqueous potassium carbonate.

Abstract: Method which includes passing a gas stream containing carbon dioxide, hydrogen sulfide, sulfur dioxide, mercaptans and other acid gases through an aqueous alkanolamine solution to remove the carbon dioxide, hydrogen sulfide, sulfur dioxide, mercaptans, etc., from the gaseous stream. Heat-stable alkanolamine salts form in the aqueous alkanolamine solution due to the acid contaminants (other than hydrogen sulfide or carbon dioxide) removed from the gas stream. A base is added to the aqueous alkanolamine solution to convert all or part of the heat-stable alkanolamine salts into alkanolamine and simple salts. The base-treated aqueous alkanolamine solution is electrodialyzed in an electrodialysis cell containing ion exchange membranes. The purified aqueous alkanolamine solution can be used again to remove carbon dioxide, etc., from the gas stream.

Abstract: The process for preparing anhydrous 2-amino-1-methoxypropane proceeds by(a) admixing a 2-amino-1-methoxypropane-containing water-containing reaction mixture, obtainable from the reaction of 1-methoxy-2-propanol with ammonia on a catalyst, with sodium hydroxide solution, forming an aqueous phase containing sodium hydroxide solution and a 2-amino-1-methoxypropane-containing phase,(b) separating off the 2-amino-1-methoxypropane-containing phase from the aqueous phase and(c) distilling the 2-amino-1-methoxypropane-containing phase, an azeotrope of water and 2-amino-1-methoxypropane, which is recycled to step (a) or (b), first being produced and anhydrous 2-amino-1-methoxypropane then being produced.

Abstract: Disclosed are a process for the preparation of a dihydroxyamino compound in which water and discoloring ingredients are removed while preventing decomposition of a dihydroxyamino compound by distilling a crude reaction liquid containing an epoxy compound and an amino compound at a specified temperature and pressure, a process for improving a yield of a dihydroxyamino compound having high purity by recirculating an aqueous solution of an amino compound recollected from a crude reaction liquid into a reaction step, and a process in which there are prevented discoloration and a yield decline of a dihydroxyamino compound.

Abstract: The invention provides a method for purification of hydroxylamine so as to have a substantial reduction of cations and anions. The method involves passing a solution of hydroxylamine through at least one strong acid ion exchange bed which has been pretreated with dilute hydrochloric acid and then through at least one strong base anion exchange resin bed which has been pretreated or regenerated with a non-metal amino or hydroxide base solution.

Abstract: The present invention relates to a process for the preparation of 2-amino-1,3-propanediol, having a content of organic impurities lower than 0.1% and inorganic impurities lower than 0.05%, comprising the following steps:a) formation of a 2-amino-1,3-propanediol salt with an acid;b) crystallization of the salt resulting from step a) from an aqueous or a hydro-organic mixture with a solvent selected from the group consisting of an alcohol of general formula R--OH, wherein R is a C.sub.1 -C.sub.6 straight or branched alkyl chain, and a mono(C.sub.1 -C.sub.3)alkylether of the (C.sub.3 -C.sub.7)alkylcellosolve group;c) elution of the free base by using ion exchangers to give an aqueous solution of said base;d) precipitation or crystallization of the solid 2-amino-1,3-propanediol from a solvent as defined in step b).

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: The present invention provides a method for rejuvenating an aqueous alkanolamine solution being at least partially deactivated from contact with an acid gas, said rejuvenation method comprising contacting said aqueous alkanolamine solution with hydrogen in the presence of a hydrotreating catalyst under hydrotreating conversion conditions including contact time sufficient to increase the acid gas sorption capacity of said aqueous alkanolamine solution.

Abstract: The present invention relates to certain purine nucleoside analogues containing a carbocyclic ring ill place of trip sugar residue, salts, esters and pharmaceutically acceptable derivatives thereof, processes for there preparation, pharmaceutical formulations containing them, and to the use of such compounds in therapy, particularly the treatment of or prophylaxis of certain viral infections.

Abstract: The instant invention is directed to a process for removing odor from alkylthioethylamine reaction product mixtures having said odor. The process comprises first contacting an alkylthioethanamine reaction product mixture with a neutralizing amount of aqueous alkali metal hydroxide to form an organic phase and an aqueous phase. Next, the organic phase is separated from the aqueous phase. After separation, a sufficient amount of an aqueous hydrohalic acid is added to the organic phase to form an alkylthioethanamine hydrohalide which has reduced odor.

Abstract: In the thermal processing of crude alkanolamines, a method of inhibiting color formation in the alkanolamines comprising adding an amount, effective for the purpose, of an alkali metal hydroxide or sulfite, or mixtures thereof.