A method for the production of olefins and ethers of a carbon material section of the water at least one tertiary olefin, by means of a synthesis and subsequent cleavage, the dimensioning a fraction as the first stage for the purification of the olefins comprises

摘要

A process for obtaining a pure tertiary olefin and/or tertiary alkyl ether from a hydrocarbon cut containing at least one etherifiable tertiary olefin, which comprises:- a) formation of a tertiary alkyl ether by contact of a hydrocarbon cut containing at least one etherifiable olefin with an alcohol in the presence of an etherification catalyst, in a reactor R1 ; b) separation of the product from (a) into an organic fraction O1, depleted in tertiary alkyl ether, and an organic fraction E1, enriched in tertiary alkyl ether; c) decomposition of the ether in the fraction E1 in a zone R2 containing a decomposition catalyst, giving a product P1 containing an alcohol and a tertiary olefin ; d) fractionation of P1 in a zone C1 thus obtaining a fraction A (containing most of the tertiary olefin, a small amount of alcohol and possibly light compounds) and a fraction B (containing most of the alcohol and possibly some non-decomposed ether) ; e) purification of fraction A by passing through a water extraction zone L1 from which an aqueous fraction C (containing most of the alcohol present) and a fraction D (containing the tertiary olefin some water, possibly light compounds and no alcohol). The process also comprises a stage (f) in which the fraction D is passed to a separation zone (Co) from which a liquid aqueous fraction (Le) is recovered, and an organic liquid fraction (Ohp1). containing most of the tertiary olefin present in D, a small amount of water and some light compounds.