Process for the Production of Xylenes

A hydrocarbon upgrading process comprising:

• (a) treating a hydrocarbon feed in at least one of a steam cracker, catalytic cracker, coker, hydrocracker, and reformer under suitable conditions to produce a first stream comprising aliphatic and aromatic hydrocarbons;
• (b) recovering from said first stream a second stream composed mainly of C6 to C9 aliphatic and aromatic hydrocarbons;
• (c) separating at least part of the second stream into a overhead stream containing C7− hydrocarbons and a bottoms stream containing C8+ hydrocarbons;
• (d) removing aliphatic hydrocarbons from said overhead stream to produce an aliphatic hydrocarbon-depleted C7− stream;
• (e) feeding said aliphatic hydrocarbon-depleted C7− stream and said bottoms stream together with hydrogen to a first reaction zone;
• (f) contacting the feed to the first reaction zone with a catalyst system effective to dealkylate C8+ single-ring aromatic hydrocarbons having at least one alkyl group containing two or more carbon atoms and transalkylate C8+ single-ring aromatic hydrocarbons having at least two methyl groups and produce a third stream having an increased toluene content or increased toluene and increased benzene content compared with said aliphatic hydrocarbon-depleted C7− stream and said bottoms stream;
• and
• (g) methylating benzene and/or toluene from said third stream with a methylating agent to produce a xylene-enriched stream.