Process for the regioselective conversion of aromatics to para- disubstituted benzenes

摘要

Processes for converting a wide variety of aromatic hydrocarbons, such as polyalkylaromatics, into commercially useful para- substituted aromatics such as para-xylene are disclosed. The aromatic hydrocarbon feed stream is first partially converted into toluene which is then subjected to a highly para-selective methylation process. The present invention therefore provides novel processes and catalysts for increasing the para-selectivity in the selective production of para- substituted aromatic compounds. From the description provided herein, those skilled in the art will appreciate that the catalysts and processes of the present invention provide greater para-selectivity at conversion rates unattained by previously known methods.