Production of para-xylene

Claim 1

IN A PROCESS FOR THE PRODUCTION OF PARA-XYLENE WHICH COMPRISES SUBJECTING TO CATALYTIC HYDROFORMING CONDITIONS A FEEDSTOCK CONTAINING A MIXTURE OF XYLENE ISOMERS TO FORM AS EFFLUENT A PRODUCT CONTAINING A MIXTURE OF XYLENE ISOMERS AND ETHYL BENZENE, WHEREIN THE CATALYST EMPLOYED IN HYDROFORMING SAID FEEDSTOCK IS A SUPPORTED NOBLE METAL SELECTED FROM THE GROUP CONSISTING OF PLATINUM AND PALLADIUM, THE IMPROVEMENT COMPRISING DIVIDING THREE PORTIONS OUT OF THE EFFLUENT, NAMELY, PARA-XYLENE,ETHYL BENZENE, AND A MIXTURE OF ORTHO- AND META-XYLENE; RECYCLING THE LATTER MIXTURE TO THE HYDROFOIRMING ZONE FOR PARTIAL ISOMERIZATION TO PARA-XYLENE,SEPARATELY AND CATALYTICALLY ISOMERIZATION IN THE PRESENCE OF SAID CATALYST THE ETHYL BENZENE PORTION TO CONVERT IT IN PART TO A MIXTURE OF XYLENE ISOMERS, MIXING THE ISOMERIZATE WITH THE HYDROFORMING EFFLUENT FOR REPORCESSING, AND RECOVERING THE PARA-XYLENE AS PRODUCT.