Process for preparation of high purity isobutylene

Abstract

Highly purified isobutylene, up to 99.9% pure, is obtained by treating a reaction mixture such as that recovered from an isobutylene-containing hydrocarbon mixture also containing an aqueous solution of an aliphatic carboxylic acid having 1 to 6 carbon atoms that has been reacted in an acidic ion exchanger and from which the unreacted hydrocarbons have been removed. The operative ingredients of the treated mixture are tertiary butyl alcohol, secondary butyl alcohol and their esters of the carboxylic acid employed. When treated with an acidic ion exchanger the carboxylic acid is first formed which inhibits the secondary butyl alcohol and secondary butyl ester of the acid from decomposing and high purity isobutylene is recovered therefrom by conventional distillation.

Dependencies are inferred from the claim text.