Patent ID: 7629498

Claim:
A process of manufacturing para-xylene, comprising: (a) contacting a pygas feedstock and methylating agent with a catalyst under reaction conditions to produce a product having para-xylene, wherein said product has higher para-xylene content than the para-xylene content of the pygas feedstock; and (f) separating said para-xylene from the product of the step (a), wherein said catalyst comprises a molecular sieve having a Diffusion Parameter for 2,2-dimethylbutane of about 0.1-15 sec-1 when measured at a temperature of 120° C. and a 2,2-dimethylbutane pressure of 8 kPa-a, said pygas comprises from about 1 to about 65 wt % benzene, from about 5 to 35 wt % toluene, from about 1 to 15 wt % C8 aromatic compounds, and at least 20 wt % of said C8 aromatic compounds is ethylbenzene, wherein at least a portion of said para-xylene is made by a process comprising the following reactions: (a1) methylating at least a portion of said ethylbenzene to form polymethylated ethylbenzene; (a2) de-ethylating at least a portion of said polymethylated ethylbenzene to form toluene and para-xylene; and (a3) methylating said toluene of (a2) to form para-xylene.