Process for the preparation of tertiary olefins by decomposition of tertiary alkyl ethers

摘要

A process for the production of tertiary olefins by decomposition of tertiary alkyl ethers comprises:- a) decomposition using a reactor R1 containing a decomposition catalyst in conditions allowing decomposition into a tertiary olefin and an alcohol; b) fractionation of the product from (a) in a zone C1, providing a fraction A containing most of the olefin, a small amount of alcohol and light compounds, and a fraction B containing most of the alcohol and possibly some non-decomposed ether; c) purification of the fraction A by passing through a water extraction zone L1 from which an aqueous fraction C, containing most of the alcohol, and a fraction D, which contains most of the olefin: D contains the olefin, water and possibly light compounds and does not contain alcohol. The process additionally comprises a stage (d) in which the fraction D is directed to a separation zone Co from which a liquid aqueous fraction Le and a liquid fraction Lc are recovered : the fraction Lc contain s most of the tertiary fraction initially present in D as well as a small quantity of water and possibly light compounds.