Abstract: Ethanol is dehydrogenated in the presence of hydrogen over a dehydrogenation catalyst, for example, a copper on silica catalyst. The liquefiable products present in the resulting intermediate reaction product mixture are selectively hydrogenated over a suitable catalyst, such as 5% ruthenium on carbon, so as selectively to hydrogenate reactive carbonyl-containing by-products to the corresponding alcohols. Butan-2-one and n-butyraldehyde are thereby hydrogenated to 2-butanol and n-butanol respectively. A two stage distillation procedure is then used to purify the selectively hydrogenated product. A first distillate of ethyl acetate, ethanol and water produced in the first distillation zone is redistilled in the second distillation zone, thereby producing a bottom product comprising, typically, from about 99.8 mol % to about 99.

Abstract: A process for the recovery of substantially pure alkyl alkanoate, such as ethyl acetate, from an impure feedstock. The impure feedstock is contacted with a selective hydrogenation catalyst in the presence of hydrogen in a selective hydrogenation zone maintained under selective hydrogenation conditions effective for selective hydrogenation of impurities containing reactive carbonyl groups thereby to hydrogenate the impurities to the corresponding alcohols. After recovery from the selective hydrogenation zone of a selectively hydrogenated reaction product mixture including the alkyl alkanoate and the corresponding alcohols, this is distilled in one or more distillation zones so as to produce substantially pure alkyl alkanoate therefrom which is recovered.

Abstract: A continuous process is described for the production of 1,4-cyclohexanedimethanol (CHDM) having a desired or predetermined trans-:cis- isomer ratio by catalytic hydrogenation of a dialkyl 1,4-cyclohexanedicarboxylate in the presence of an ester hydrogenation catalyst. The process is capable of being operated for an extended period of time during which the hydrogenation catalyst declines in catalytic activity and comprises feeding a vaporous mixture of the dialkyl 1,4-cyclohexanedicarboxylate and hydrogen to a hydrogenation zone containing the hydrogenation catalyst and recovering CHDM product. The degree of conversion of the dialkyl 1,4-cyclohexanedicarboxylate at a particular combination of temperature and pressure is related to the trans-:cis- isomer ratio of the CHDM product and may be varied by adjusting at least one feed condition selected from (i) the dialkyl 1,4-cyclohexanedicarboxylate feed rate and (ii) the hydrogen-containing gas:dialkyl 1,4-cyclohexanedicarboxylate molar ratio.

Abstract: A process is described for the production of cyclohexanedimethanol by hydrogenation of a dialkyl cyclohexanedicarboxylate which comprises:(a) providing a hydrogenation zone containing a charge of a granular heterogeneous ester hydrogenation catalyst;(b) forming a vaporous feed stream of a hydrogen-containing gas,and a hydrogenatable material comprising a dialkyl cyclohexanedicarboxylate at a feed temperature which is in the range of from about 150.degree. C. to about 350.degree. C. and which is above the dew point of the feed stream and at a feed pressure in the range of from about 150 psia (about 10.34 bar) to about 2000 psia (about 137.

Abstract: A process is described for the production of a dialkyl maleate by reaction of maleic anhydride with an alkyl alcohol in a monoesterification zone to form the corresponding monoalkyl maleate, followed by reaction of resulting monoalkyl maleate with further alkyl alcohol to form the corresponding dialkyl maleate, which includes the steps of supplying a first liquid feed comprising said monoalkyl maleate to a secondary esterification zone containing a charge of a solid esterification catalyst, supplying a second feed stream comprising said alkyl alcohol to said secondary esterification zone, maintaining said secondary esterification zone at an elevated temperature sufficient to form or to maintain therein a vaporous stream containing said alkyl alcohol, intimately contacting said first liquid feed in said secondary esterification zone in the presence of said catalyst with said vaporous feed stream, recovering from said secondary esterification zone a vaporous effluent stream containing, in addition to alkyl alco

Abstract: A continuous process is described for the production of a substantially acid free dialkyl maleate, for example diethyl maleate, from a feed stream containing a major amount of dialkyl maleate and a minor amount of the corresponding monoalkyl maleate. This comprises continuously distilling the feed stream in a primary distillation zone, which can comprise a single distillation column or a series of distillation columns connected in series, so as to give (i) a bottom fraction containing monoalkyl maleate and dialkyl maleate in admixture, (ii) a vaporous fraction comprising alkanol, and (iii) an intermediate fraction that is substantially free from alkanol and comprises a major proportion of diethyl maleate and a minor proportion of maleic anhydride. The intermediate fraction (iii) is redistilled in a secondary distillation zone to yield (i) an overhead fraction containing maleic anhydride and (ii) a bottom fraction containing substantially acid free dialkyl maleate.

Abstract: Butane-1,4-diol is produced by vapor phase hydrogenolysis of an alkyl ester of a C.sub.4 dicarboxylic acid, e.g. diethyl maleate, over a reduced Cu-Cr or Cu-Zn mixed oxide catalyst. Two adiabatic hydrogenolysis zones are used. The mixture exiting the first of these zones is cooled (by, for example, 5.degree. C.) and the resulting cooled mixture is fed to the second zone in which is reequilibriates at a lower temperature to increase the butane-1,4-diol yield at the expense of gamma-butyrolactone. Typical reaction conditions include use of temperatures of 150.degree. C. to 200.degree. C., pressures of 25 to 70 bar, and a H.sub.2 :ester molar ratio of 100:1 to 800:1. When using a maleate ester it is often advantageous to hydrogenate this to the corresponding succinate ester in an upstream hydrogenation zone prior to entry to the first hyrogenolysis zone.