Patent ID: 7838713

Claim:
A process for separating para-xylene from a feed stream comprising C8 aromatic hydrocarbons and at least one C9 aromatic hydrocarbon component, the process comprising: (a) contacting a first adsorbent comprising a Y zeolite or an X zeolite with the feed stream and a first desorbent stream comprising a first desorbent component having a boiling point of at least about 150° C. in a first adsorptive separation zone to produce a first extract stream comprising para-xylene and the first desorbent component and a first raffinate stream comprising para-xylene depleted C8 aromatic hydrocarbons, the C9 aromatic hydrocarbon component, and the first desorbent component; (b) passing the first extract stream to a first extract distillation zone to produce a second desorbent stream comprising the first desorbent component and a para-xylene product stream; (c) passing the first raffinate stream to a raffinate distillation zone to produce a third desorbent stream comprising the first desorbent component and the C9 aromatic hydrocarbon component and a raffinate product stream comprising the para-xylene depleted C8 aromatic hydrocarbons; and (d) passing at least a portion of the third desorbent stream and a stream comprising a second desorbent component to a second adsorptive separation zone comprising a second adsorbent to produce a second extract stream comprising the first desorbent component and the second desorbent component and a second raffinate stream comprising the C9 aromatic hydrocarbon component and the second desorbent component.