PRODUCTION OF PARAXYLENE AND PRODUCTION UNIT THEREFOR

PURPOSE: To efficiently obtain p-xylene useful as e.g. a raw material for polyesters by providing a p-xylene concentration process between xylene isomerization and p-xylene separation process to maximally utilize the performance of a zeolite-based adsorptive separator. CONSTITUTION: The objective p-xylene 5 is obtained by providing a p-xylene concentration process such as an o-xylene distillation/separation process 105A between a xylene isomerization process 103 and a zeolite-based adsorptive separation process 102 for p-xylene. It is preferable that the p-xylene-poor component drawn from the p-xylene concentration process be treated in the isomerization process 103 and the p-xylene-contg. component produced be subjected again to the p-xylene concentration process and then separated in the p-xylene separation process.