Production of esters

A process for the manufacture of an alkyl ester of an aliphatic carboxylic acid comprising the steps of:

• a) supplying a first feed stream comprising carbon monoxide and an alkene of formula CnH2n to a reactor;
• b) supplying a second feed stream comprising an alkyl alcohol, having a formula R—OH where R is an optionally substituted alkyl group, the reactor;
• c) reacting together said first and second feed streams in the reactor in the presence of a carbonylation catalyst, which catalyses the carbonylation reaction between carbon monoxide and the alkene, to form a product comprising an alkyl alkanoate having the formula CnH2n+1COOR
• characterised in that the ratio of alkyl alcohol to alkyl alkanoate present in the reactor is greater than the ratio of alkyl alcohol to alkyl alkanoate present in an azeotropic mixture of the alkyl alcohol and alkyl alkanoate.

A continuous process for the manufacture of methyl propionate comprising the steps of:

• a) supplying a first feed stream comprising carbon monoxide and ethylene in the gas phase to a reactor;
• b) supplying a second feed stream comprising methanol to the reaction;
• c) reacting together said first and second feed streams in the reactor in the presence of a carbonylation catalyst, which catalyses the carbonylation reaction between carbon monoxide and ethylene, to form a product comprising methyl propionate;
• characterised in that the ratio of methanol to methyl propionate present in the reactor is in the range from 47:53-99:1 weight %.

A process for the manufacture of methyl propionate comprising the steps of:

• a) supplying a first feed stream comprising carbon monoxide and ethylene in the gas phase to a reactor;
• b) supplying a second feed stream comprising methanol to the reactor;
• c) reacting together said first and second feed streams in the reactor in the presence of a carbonylation catalyst, which catalyses the carbonylation reaction between carbon monoxide and ethylene, to form a product comprising methyl propionate;
• characterised in that the ratio of methanol to methyl propionate present in the reactor is in the range from 47:53-99:1 weight %.