摘要:
A process for the production of a dialkyl carbonate and a diol from a cyclic carbonate and an aliphatic monohydric alcohol wherein the cyclic carbonate and aliphatic monohydric alcohol are reacted in the presence of a transesterification catalyst to form a crude product stream which contains a dialkyl carbonate, a diol, a hydroxy alkyl carbonate, which is formed as an intermediate of the two step transesterification reaction, unreacted aliphatic monohydric alcohol and unreacted cyclic carbonate. The dialkyl carbonate and unreacted aliphatic monohydric alcohol are separated from the crude product stream and then the hydroxy alkyl carbonate is diminished, reduced or eliminated from the crude product stream, prior to the separation and purification steps needed to recover the diol, resulting in improved yields and product purity.
摘要:
In a process for producing cyclohexylbenzene, hydrogen and a liquid feed comprising benzene are introduced into a reaction zone and are contacted in the reaction zone under hydroalkylation conditions to produce cyclohexylbenzene. An effluent stream comprising cyclohexylbenzene and unreacted benzene is removed from the reaction zone and is divided into at least first and second portions, wherein the mass ratio of the effluent stream first portion to the effluent stream second portion is at least 2: 1. The effluent stream first portion is then cooled and the cooled effluent stream first portion is recycled to the reaction zone.
摘要:
In a process for producing cyclohexylbenzene, benzene and hydrogen are fed to at least one reaction zone. The benzene and hydrogen are then contacted in the at least one reaction zone under hydroalkylation conditions with a catalyst system comprising a molecular sieve having an X-ray diffraction pattern including d-spacing maxima at 12.4±0.25, 6.9±0.15, 3.57±0.07 and 3.42±0.07 Angstrom, and at least one hydrogenation metal to produce an effluent containing cyclohexylbenzene. The ratio of the total number of moles of hydrogen fed to said at least one reaction zone to the number of moles of benzene fed to said at least one reaction zone is between 0.4 and 0.9: 1.
摘要:
An integrated process for the production of a dialkyl carbonate and a diol from an alkylene oxide, carbon dioxide and an aliphatic monohydric alcohol is described in which an alkylene oxide if first reacted with carbon dioxide in the presence of a homogeneous carbonation catalyst to provide a corresponding cyclic carbonate and the cyclic carbonate is then reacted with an aliphatic monohydric alcohol in the presence of the homogeneous carbonation catalyst and/or a heterogeneous transesterification catalyst and recycling the homogeneous carbonation catalyst to provide a corresponding dialkyl carbonate and diol.
摘要:
In a process for producing cyclohexylbenzene, hydrogen and a liquid feed comprising benzene are introduced into a reaction zone and are contacted in the reaction zone under hydroalkylation conditions to produce cyclohexylbenzene. An effluent stream comprising cyclohexylbenzene and unreacted benzene is removed from the reaction zone and is divided into at least first and second portions, wherein the mass ratio of the effluent stream first portion to the effluent stream second portion is at least 2: 1. The effluent stream first portion is then cooled and the cooled effluent stream first portion is recycled to the reaction zone.
摘要:
In a process for oxidizing a hydrocarbon to the corresponding hydroperoxide, alcohol, ketone, carboxylic acid or dicarboxylic acid, a reaction medium comprising a hydrocarbon is contacted with an oxygen-containing gas in a reaction zone and in the presence of a catalyst comprising a cyclic imide. During the oxidation process, a portion of the reaction medium is continuously or intermittently removed from the reaction zone, is stripped of water and organic acid impurities and then returned to the reaction zone.
摘要:
In a process for producing cyclohexylbenzene, benzene and hydrogen are fed to at least one reaction zone. The benzene and hydrogen are then contacted in the at least one reaction zone under hydroalkylation conditions with a catalyst system comprising a molecular sieve having an X-ray diffraction pattern including d-spacing maxima at 12.4±0.25, 6.9±0.15, 3.57±0.07 and 3.42±0.07 Angstrom, and at least one hydrogenation metal to produce an effluent containing cyclohexylbenzene. The catalyst system has an acid- to-metal molar ratio of from about 75 to about 750.
摘要:
A process for oligomerizing isobutene comprises contacting a feedstock comprising isobutene with a catalyst comprising a MCM-22 family molecular sieve under conditions effective to oligomerize the isobutene, wherein said conditions including a temperature from about 45°C to less than 140°C. The isobutene may be a component of a hydrocarbon feedstock containing at least one additional C4 alkene.
摘要:
In a process for producing cyclohexylbenzene, benzene and hydrogen are fed to at least one reaction zone. The benzene and hydrogen are then contacted in the at least one reaction zone under hydroalkylation conditions with a catalyst system comprising a molecular sieve having an X-ray diffraction pattern including d-spacing maxima at 12.4±0.25, 6.9±0.15, 3.57±0.07 and 3.42±0.07 Angstrom, and at least one hydrogenation metal to produce an effluent containing cyclohexylbenzene. The catalyst system has an acid- to-metal molar ratio of from about 75 to about 750.