Abstract: The present invention is directed to a process for the manufacture of methyl limonitrile comprising a mixture of 3,7-dimethyl-2,6-nonadiene nitrile, 3,7-dimethyl-3,6-nonadiene nitrile and 7-methyl-3-methylene-6-nonene nitrile comprising the following steps: a) reacting 6-methyl-5-octen-2-one with cyano acetic acid and removing carbon dioxide and water, wherein the reaction and the removal of carbon dioxide and water are performed in the presence of a base and a co-base 1 in an organic solvent, and wherein the organic solvent is a solvent which forms a heteroazeotrop with water; b) removing the solvent and the base of the reaction mixture obtained after having performed step a) or step c) by distillation to obtain a reaction mixture, whereby this step may optionally be performed in the presence of a co-base 2; c) isomerizing the reaction mixture obtained after having performed step a) or step b) to obtain an isomerized reaction mixture in the presence of a co-base 2; whereby step b) can be performed before or

Abstract: An increase in the differential pressure in the distillation tower for the recovery of (meth)acrylonitrile is suppressed, and a stable and efficient operation is performed over a long time. A method for recovering (meth)acrylonitrile from a mixture containing (meth)acrylonitrile, acetonitrile and unsaturated compounds, in which the mixture is introduced into a distillation tower, distillation is performed under the conditions that the overhead liquid of the distillation tower contains (meth)acrylonitrile, acetonitrile is drawn out from the bottom and/or a side stream of the distillation tower, and a liquid containing the unsaturated compounds is drawn out from a site higher in position than the position of drawing acetonitrile.

Abstract: An industrially advantageous method for producing a high purity terminal olefin is disclosed, comprising the steps of (a) contacting a mixture comprising a terminal olefin represented by formula (1): and one or more corresponding internal olefins as impurities, with a brominating agent in the presence of water or an alcohol, to convert the internal olefin(s) to compound(s) having a higher boiling point than the terminal olefin; and (b) purifying the terminal olefin by distillation from the reaction mixture.

Abstract: An increase in the differential pressure in the distillation tower for the recovery of (meth)acrylonitrile is suppressed, and a stable and efficient operation is performed over a long time. A method for recovering (meth)acrylonitrile from a mixture containing (meth)acrylonitrile, acetonitrile and unsaturated compounds, in which the mixture is introduced into a distillation tower, distillation is performed under the conditions that the overhead liquid of the distillation tower contains (meth)acrylonitrile, acetonitrile is drawn out from the bottom and/or a side stream of the distillation tower, and a liquid containing the unsaturated compounds is drawn out from a site higher in position than the position of drawing acetonitrile.

Abstract: A process is described for preparing 3-pentenenitrile, characterized by the following process steps: (a) reacting 1,3-butadiene with hydrogen cyanide over at least one catalyst to obtain a stream 1 which comprises 3-pentenenitrile, 2-methyl-3-butenenitrile, the at least one catalyst and 1,3-butadiene, (b) distilling stream 1 in a column to obtain a high-1,3-butadiene stream 2 as the top product and a low-1,3-butadiene stream 3 as the bottom product which comprises 3-pentenenitrile, the at least one catalyst and 2-methyl-3-butenenitrile, (c) distilling stream 3 in a column to obtain a stream 4 as the top product which comprises 1,3-butadiene, a stream 5 which comprises 3-pentenenitrile and 2-methyl-3-butenenitrile at a side draw of the column, and a stream 6 as the bottom product which comprises the at least one catalyst, (d) distilling stream 5 to obtain a stream 7 as the top product which comprises 2-methyl-3-butenenitrile, and a stream 8 as the bottom product which comprises 3-pentenenitrile.

Abstract: A process of producing HPLC grade acetonitrile (UV cutoff<190) comprising a multistep distillation under reflux conditions followed by acidic ion exchange resin treatment to remove essentially all impurities from the acetonitrile.

Abstract: An improved process for the production of unsaturated carboxylic acids and unsaturated nitriles from their corresponding C3 to C5 alkanes, or mixtures of C3 to C5 alkanes and alkenes, that involves oxidation in the presence of a supported Mo-V-based mixed metal oxide catalyst in a multi-stage reaction system which employs both separation of the oxidation product from one or more intermediate effluent streams, as well as feeding additional oxygen to reaction zones subsequent to the first reaction zone.

Abstract: A process for the recovery of acrylonitrile or methacrylonitrile from an aqueous solution comprising subjecting the said solution to a water extractive distillation by feeding the solution to a distillation column and performing said extractive distillation and using solvent water introduced at the top of said column, removing a first overhead vapor stream of acrylonitrile or methacrylonitrile with some water from the top of the column, and a first liquid stream containing water and impurities from the bottom of the column, the contents of said column maintained at a substantially neutral pH by adding a sufficient amount of at least one alkaline compound selected from ammonium carbonate, ammonium bicarbonate, ammonium carbamate, and alkylene diamines to the overhead decanter and/or to the solvent water.

Abstract: By means of a new process for the resolution of racemic 3-aminopentanenitrile, enantiomerically enriched 3-aminopentanenitrile or its salts can be obtained. For this, racemic 3-aminopentanenitrile is reacted with an enantiomerically enriched organic acid and one of the two diastereomeric salts formed is separated off and then converted into the enantiomerically enriched 3-aminopentanenitrile or its salts.

Abstract: A process for the recovery and purification of olefinically unsaturated nitrites from a process stream produced by the ammoxidation of a hydrocarbon feedstock comprising contacting the process stream comprising olefinically unsaturated nitrile with an aqueous quench liquid in a quench apparatus to produce a gaseous quench effluent comprising olefinically unsaturated nitrile; contacting the gaseous quench effluent with a liquid comprising water in an absorber apparatus to form an aqueous mixture comprising absorbed olefinically unsaturated nitrile; withdrawing from the absorber apparatus a side-draw stream comprising water and a bottoms stream comprising olefinically unsaturated nitrile; introducing the bottoms stream to a first distillation column where the bottoms stream is distilled in an extractive distillation to form a top fraction comprising olefinically unsaturated nitrile, and directing the side-draw stream comprising water to the upper portion of the first distillation column to assist with the extra

Abstract: A process is described for the recovery of acrylonitrile from an ammoxidation reactor effluent stream containing acrylonitrile, water, and organic impurities. The process includes the steps of (a) quenching an ammoxidation reactor effluent stream that includes acrylonitrile, water, and organic impurities with an aqueous quench stream, thereby producing a cooled reactor effluent stream; (b) passing the cooled reactor effluent stream through an absorption column, thereby generating an absorber bottoms stream that includes water, acrylonitrile, and organic impurities; and (c) passing the absorber bottoms stream through a single recovery/stripper column, generating an acrylonitrile-rich overhead stream, a lean water side stream, and a recovery/stripper bottoms stream that includes organic impurities. The acrylonitrile-rich overhead stream can be passed through a decanter to separate water from acrylonitrile. The lean water side stream can be recycled for use in the absorption column.

Abstract: A process is provided for the distillative separation of pentene nitrile isomers which have a relative volatility alpha ranging from 1.0 to 1.3 in the pressure range from 1 to 500 kPa, wherein the distillation is carried out in the presence of a liquid diluent which forms with the pentene nitrile isomers, under the same pressure conditions, azeotropes whose relative volatility alpha is higher than that of the pentene nitrile isomers to be separated.

Abstract: A process for the enhanced recovery and operation of hydrogen cyanide (HCN)/heads column obtained from the reactor effluent of an ammoxidation reaction of propane, propylene or isobutylene by reducing the polymer formation above the feed tray in the heads tower.

Abstract: A process for the recovery of acrylonitrile or methacrylonitrile from an aqueous solution comprising subjecting the said solution to a water extractive distillation by feeding the solution to a distillation column and performing said extractive distillation and using solvent water introduced at the top of said column, removing a first overhead vapor stream of acrylonitrile or methacrylonitrile with some water from the top of the column, and a first liquid stream containing water and impurities from the bottom of the column, the contents of said column maintained at a substantially neutral pH by adding a sufficient amount of at least one alkaline compound selected from ammonium carbonate, ammonium bicarbonate, ammonium carbamate, and alkylene diamines to the overhead decanter and/or to the solvent water.

Abstract: A process of producing HPLC grade acetonitrile (UV cutoff<190) comprising a multistep distillation under reflux conditions followed by acidic ion exchange resin treatment to remove essentially all impurities from the acetonitrile.

Abstract: By means of a new process for the resolution of racemic 3-aminopentanenitrile, enantiomerically enriched 3-aminopentanenitrile or its salts can be obtained. For this, racemic 3-aminopentanenitrile is reacted with an enantiomerically enriched organic acid and one of the two diastereomeric salts formed is separated off and then converted into the enantiomerically enriched 3-aminopentanenitrile or its salts.

Abstract: A process is provided for the distillative separation of pentene nitrile isomers which have a relative volatility alpha ranging from 1.0 to 1.3 in the pressure range from 1 to 500 kPa, wherein the distillation is carried out in the presence of a liquid diluent which forms with the pentene nitrile isomers, under the same pressure conditions, azeotropes whose relative volatility alpha is higher than that of the pentene nitrile isomers to be separated.

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

Abstract: Process for isolating one or more organic substances from a gas mixture in which these organic substances are present, in which the gas mixture is subjected to a quenching in a column, characterized in that quenching is carried out in the upper part of the column and the quenching liquid is subjected to stripping in the lower part of the column.

Abstract: A method for the purification of crude acetonitrile comprising distilling the crude acetonitrile in a first fractional distillation column at below atmospheric pressure, withdrawing a first side draw fraction comprising acetonitrile, distilling the first side draw fraction in a second fractional distillation column at super atmospheric pressure, and withdrawing from the second distillation a second side draw fraction comprising purified acetonitrile.

Abstract: A process for the enhanced recovery and operation of hydrogen cyanide (HCN)/heads column obtained from the reactor effluent of an ammoxidation reaction of propane, propylene or isobutylene by reducing the polymer formation above the feed tray in the heads tower.

Abstract: A process for the enhanced recovery and operation of hydrogen cyanide (HCN) / heads column obtained from the reactor effluent of an ammoxidation reaction of propane, propylene or isobutylene by reducing the polymer formation above the feed tray in the heads tower.

Abstract: A method for improving purification efficiency when distilling off aldehyde contaminants during chemical manufacturing processes by adding a substituted aromatic amine having electron donating group substituents prior to the distillation column. The method is particularly useful for removal of aldehydes such as acrolein, generated as a by-product of acrylonitrile manufacture. Preferred aromatic amines are 2-amino aniline, 3,4-dimethyl aniline and 4-ethyl aniline.

Abstract: An alpha-tocopherol is disclosed as a polymerization inhibitor effective against vinyl monomer polymerization. Alpha-tocopherol was found to inhibit polymerization of acrylonitrile and diolefines such as isoprene and butadiene. Alpha-tocopherol was found to interact synergistically with hydroquinone in inhibiting polymerization of acrylonitrile.

Abstract: A process for removing acrolein from a gaseous or liquid mixture, in one case aqueous solutions, involving contacting the mixture with a compound selected from the group consisting of sodium hypochlorite; an acid salt of hydroxylamine; a urea compound such as urea itself or thiourea; sodium bisulfite and 4,4-dimethyl-1-oxa-3-azacyclopentane in an amount effective to substantially remove acrolein has been discovered. The process works particularly well in selectively scavenging acrolein from aqueous solutions containing acrylonitrile.

Abstract: The invention comprises a method of inhibiting the formation of foulants and residues, gums and precipitates, polymeric tars and other highly oxidized carbonaceous tars which can be formed in the process of manufacture and recovery of acrylonitrile. The method comprises adding to the liquid or gaseous phases passing through, or stored in acrylonitrile process equipment, an effective antifouling amount of a dispersant which is stable in the environment within an acrylonitrile process and is neutral to the equipment used for the manufacture of acrylonitrile.

Abstract: The invention provides a method for the inhibition of fouling in petrochemical processes. The method comprises adding from about 0.1 to about 10,000 parts per million sulfonated oils, sulfonated fatty acids, sulfated oils, sulfated fatty acids, or naphthalene sulfonate formaldehyde condensates to a petrochemical process to disperse water insoluble foulant into an aqueous system.

Abstract: Disclosed herein is a process for removing acrolein from a gaseous or liquid mixture, in one case aqueous solutions, involving contacting the mixture with a compound selected from the group consisting of sodium hypochlorite; an acid salt of hydroxylamine; a urea compound such as urea itself or thiourea; sodium bisulfite and 4,4-dimethyl-1-oxa-3-azacyclopentane in an amount effective to substantially remove acrolein has been discovered. The process works particularly well in selectively scavenging acrolein from aqueous solutions containing acrylonitrile.

Abstract: A method for removing hydrogen cyanide from a hydrogen cyanide-contaminated organic liquid includes the steps of contacting the hydrogen cyanide-contaminated organic liquid with a metal alkoxide to generate a metal cyanide salt and an alkanol and then separating the organic liquid from the metal cyanide salt and the alkanol.

Abstract: Separation of an aliphatic aminonitrile or an aliphatic diamine from a mixture containing the corresponding cyclic, aliphatic, mono-unsaturated amine by adding caustic compound to the mixture and then distilling the aminonitrile or the diamine at a temperature less than 170.degree. C. and at a pressure of less than 1 atmosphere.

Abstract: The present invention relates to a process for reducing the concentration of acrylontrile in an aqueous-acrylonitrile vapor stream. The process involves feeding the aqueous-acrylontrile vapor stream to a primary condenser maintained at a temperature and pressure so that a substantial amount of the water is condensed and the acrylonitrile is maintained in the vapor phase. The vapor containing the acrylonitrile from the first condenser is introduced to a secondary condenser maintained at a temperature and pressure so that substantially all the vapor is condensed. The condensate exiting the secondary condenser is introduced to a decanter where the acrylonitrile containing organic phase of the condensate is separated and recovered from the aqueous phase. The aqueous phase is recycled to the primary condenser to significantly reduce the acrylonitrile level in the aqueous phase and enhanced the separation.

Abstract: Excess amounts of a pure form of acrylonitrile are reacted with other reactants in the production of various compounds such as 2-acrylamido-2-methyl propane sulfonic acid. Accordingly, large amounts of acrylonitrile remain unreacted and present with other contaminants. The present invention is directed toward the purification of such unreacted acrylonitrile and the purified acrylonitrile obtained from such a purification process. The purification is carried out by treating the unreacted acrylonitrile with a base and removing salts formed. The treated material is fed to a heat exchanger which heats the material preferably under vacuum to about 120.degree. F. and provides a heated fluid material. This heated fluid material is pumped to a lower area of a distillation tower which is maintained under vacuum and includes a plurality of distillation trays.