Hydrocarbonylation of methanol to ethanol in the presence of added compounds
AssigneeThe British Petroleum Company p.l.c.
InventorsJohn L. Barclay, Brian R. Gane
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Abstract
Ethanol is produced by reacting methanol with carbon dioxide and hydrogen at a temperature in the range 150.degree. to 250.degree. C., a pressure in the range 100 to 300 bars and a residence time in the range 10 minutes to 8 hours in the presence of: (i) a cobalt-containing catalyst optionally promoted with iodine, bromine or an organo-phosphorus compound and optionally in the presence of a stabilizer and, (ii) an additive which may be a monocarboxylic acid and/or a derivative thereof and, optionally, a non-polar solvent such as an alkane, benzene or an alkyl-substituted benzene. The preferred additives are acetic acid and methyl acetate. The presence of the additive increases the total realizable yield and selectivity to ethanol.
Claims23
A process for the production of ethanol which process comprises contacting a mixture of methanol and synthesis gas at elevated temperature and pressure with a cobalt-containing catalyst in the presence of an additive which is deliberately added to the reaction system, said additive being selected from the group consisting of monocarboxylic acids and derivatives thereof having the formula ##STR2## wherein the substituent R is selected from hydrocarbyl groups and oxygen-containing hydrocarbyl groups and the substituent X is selected from the groups --OR.sup.1 and --O--CO--R.sup.2 in which R.sup.1 is selected from the group consisting of a hydrogen atom, a hydrocarbyl group and an oxygen-containing hydrocarbyl group and R.sup.2 is selected from the group consisting of a hydrocarbyl group and an oxygen-containing hydrocarbyl group, said additive of formula I being added in an amount such that the molar ratio of additive to free methanol contacted with the catalyst is in the range of from 0.1:1 to 1.5:1, provided that when R and R.sup.1 are both methyl then the molar ratio of additive to free methanol contacted with the catalyst is in the range of from about 0.1:1 to 0.7:1.
Dependencies are inferred from the claim text.