Verfahren zur Herstellung von Olefinen und Ether aus einen Kohlenwasserstoffschnitt der wenigstens ein tertiäres Olefin enthält, durch Synthese und nachfolgende Spaltung, das eine Fraktionnierung als erste Stufe zur Reinigung der Olefine umfasst

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.