Process for the preparation of dialkyle carbonates

摘要

Dialkyl carbonates can be prepared by reaction of carbon monoxide with alkyl nitrites in a continuous gas phase reaction, a platinum metal catalyst on an aluminosilicate zeolite having acidic centres, preferably in the H<+> form, being employed as the support and, if appropriate, an addition of a compound of antimony, bismuth, aluminium, copper, vanadium, niobium, tantalum, tin, iron, cobalt, nickel or a mixture of several of them being employed on this catalyst and hydrogen halide being added intermittently or continuously in the course of the reaction. In this process, the dialkyl carbonates are formed in nearly quantitative selectivity; the corresponding dialkyl-oxalates can in most cases not be detected.