Patent ID: 7128883

Claim:
A dual-transalkylation apparatus for conversion of aromatic hydrocarbons comprising: a) a first-transalkylation unit comprising a liquid-phase reaction vessel, wherein benzene and C 9 + alkylaromatics are contacted with a first-transalkylation catalyst under transalkylation conditions to produce a first-transalkylation product stream comprising ethylbenzene; b) a first column, wherein the first-transalkylation product stream and a second-transalkylation product stream are separated to produce a fractionated-benzene stream and a xylene-plus stream; c) a second column, wherein the xylene-plus stream is separated into a xylene-enriched stream, which is recovered as a product, and a C 9 + alkylaromatic-enriched stream; and d) a second-transalkylation unit comprising a gas-phase reaction vessel, wherein a toluene feed stream is contacted with a second-transalkylation catalyst under transalkylation conditions to produce the second-transalkylation product stream.