A catalyst composition, a process for producing the composition and a hydrocarbon conversion process for converting a C.sub.9 + aromatic compound to a C.sub.6 to C.sub.8 aromatic hydrocarbon such as a xylene are disclosed. The composition comprises a zeolite having incorporated therein a promoter comprising carbon and a metal or metal oxide. The composition can be produced by incorporating a metal compound into the zeolite followed by thermal treatment of the resulting zeolite with a hydrocarbon. The hydrocarbon conversion process comprises contacting a fluid which comprises a C.sub.9 + aromatic compound with the catalyst composition under a condition sufficient to effect the conversion of a C.sub.9 + aromatic compound to a C.sub.6 to C.sub.8 aromatic hydrocarbon.