PROCESS FOR PRODUCING PARA-XYLENE, COMPRISING ONE ADSORPTION AND TWO ISOMERIZATION STEPS

摘要

PATENT INSTITUT FRANCAIS DU PETROLE PROCESS FOR PRODUCING PARA-XYLENE, COMPRISING ONE ADSORPTION STEP AND TWO ISOMERIZATION STEPS Philibert LEFLAIVE, Luc WOLFF and Gerard HOTIER ABSTRACT A process for producing para-xylene from a hydrocarbon feed is described in which an adsorption column operating as a simulated moving bed with at least five zones delivers an extract, a 2-raffmate and an intermediate raffinate. The extract is distilled and the distillate is optionally re-crystallized to recover para-xylene with a purity of at least 99.7%. The 2-raffmate is distilled then isomerized in a reactor preferably operating in the liquid phase and at a low temperature. The intermediate raffinate with an enriched ethylbenzene content is distilled then isomerized in the vapour phase. Figure 1 to be published.