Disclosed are processes for conversion of a feedstock comprising C.sub.8+ aromatic hydrocarbons to lighter aromatic products in which the feedstock and optionally hydrogen are contacted in the presence of the catalyst composition under conversion conditions effective to dealkylate and transalkylate said C.sub.8+ aromatic hydrocarbons to produce said lighter aromatic products comprising benzene, toluene and xylene. The catalyst composition comprises a zeolite, a first metal, and a second metal, and is treated with a source of sulfur and/or a source of steam.

Disclosed are processes for conversion of a feedstock comprising C.sub.8+ aromatic hydrocarbons to lighter aromatic products in which the feedstock and optionally hydrogen are contacted in the presence of the catalyst composition under conversion conditions effective to dealkylate and transalkylate said C.sub.8+ aromatic hydrocarbons to produce said lighter aromatic products comprising benzene, toluene and xylene. The catalyst composition comprises a zeolite, a first metal, and a second metal, and is treated with a source of sulfur and/or a source of steam.

A catalyst for synthesizing aromatic hydrocarbons, a preparation method thereof and a method for synthesizing aromatic hydrocarbons by using the catalyst. The catalyst comprises acidic molecular sieve particles and zinc-aluminum composite oxide particles. The catalyst has relatively high selectivity to aromatic hydrocarbons, particularly BTX, stable performance, and a long single-pass life.

Disclosed are processes for conversion of a feedstock comprising C.sub.8+ aromatic hydrocarbons to lighter aromatic products in which the feedstock and optionally hydrogen are contacted in the presence of the catalyst composition under conversion conditions effective to dealkylate and transalkylate said C.sub.8+ aromatic hydrocarbons to produce said lighter aromatic products comprising benzene, toluene and xylene. The catalyst composition comprises a zeolite, a first metal, and a second metal, and is treated with a source of sulfur and/or a source of steam.

Disclosed are processes for conversion of a feedstock comprising C.sub.8+ aromatic hydrocarbons to lighter aromatic products in which the feedstock and optionally hydrogen are contacted in the presence of the catalyst composition under conversion conditions effective to dealkylate and transalkylate said C.sub.8+ aromatic hydrocarbons to produce said lighter aromatic products comprising benzene, toluene and xylene. The catalyst composition comprises a zeolite, a first metal, and a second metal, and is treated with a source of sulfur and/or a source of steam.

Disclosed are processes for conversion of a feedstock comprising C.sub.8+ aromatic hydrocarbons to lighter aromatic products in which the feedstock and optionally hydrogen are contacted in the presence of a first and a second catalyst composition under conversion conditions effective to produce said lighter aromatic products comprising benzene, toluene and xylene. In the process, the C.sub.8+ aromatic hydrocarbons are dealkylated to form C.sub.6-C.sub.7 aromatic hydrocarbon and the C.sub.2+ olefins formed are saturated. The remaining C.sub.8+ aromatic hydrocarbons are transalkylated with the C.sub.6-C.sub.7 aromatic hydrocarbon. The first and second catalyst compositions each comprise a zeolite, a first metal, and optionally a second metal, and are treated with a source of sulfur and/or a source of steam.

A catalyst for synthesizing aromatic hydrocarbons, a preparation method thereof and a method for synthesizing aromatic hydrocarbons by using the catalyst. The catalyst comprises acidic molecular sieve particles and zinc-aluminum composite oxide particles. The catalyst has relatively high selectivity to aromatic hydrocarbons, particularly BTX, stable performance, and a long single-pass life.