Process for the alkylation of paraffins.

摘要

The invention relates to an alkylation process in which a charge, comprising at least one isoparaffin and at least one olefin containing from 2 to 6 carbon atoms per molecule, is treated in the presence of a solid alkylation catalyst; the said process comprising: a) introducing the following compounds and bringing them into contact with the catalyst present in a reaction region R: (i) the said charge, preferably introduced at least at the inlet of the region R, (ii) the liquid effluent described in b), introduced at least at the inlet of the region R, preferably entirely introduced at the inlet of the region R and, (iii) the liquid effluent described in d), preferably introduced at least at the inlet of the region R, b) recycling part of the liquid effluent exiting from the reaction region R to the inlet of the said region R, c) introducing another part of the liquid effluent exiting from the reaction region R into an isobutane/normal-butane/alkylate separation region S, d) recycling the major part of the liquid effluent which is rich in isobutane from the region S to the reaction region R, e) obtaining an alkylate as product, drawn off from the lower part of the region S, and, f) obtaining normal-butane by purging (blowing-off, draining, bleeding, venting) from the region S, the process being characterised by the use of a specific catalyst, especially comprising sulphuric acid impregnated on a porous support. <IMAGE>