Patent ID: 7396966

Claim:
An integrated process for producing an alkylbenzene, the process comprising: a) dehydrogenating a feedstock comprising a paraffin having from 6 to 22 carbon atoms per molecule in a dehydrogenation zone and recovering therefrom a dehydrogenated product comprising a mono-olefin, less than 85 mass-percent paraffins, benzene and at least about 2 mass-percent aromatic by-products having from 7 to 22 carbon atoms per molecule; b) selectively removing at least a portion of the aromatic by-products from at least a portion of the dehydrogenated product by at least intermittently passing at least a portion of the dehydrogenated product to an on-stream zone containing sorbent at conditions effective to selectively sorb aromatic by-products on the sorbent and to produce a sorption effluent stream comprising the mono-olefin and the paraffin and having a reduced concentration of aromatic by-products; c) regenerating the sorbent in an off-stream zone containing sorbent, the sorbent in the off-stream zone having aromatic by-products sorbed thereon from having been on-stream in step b, said regeneration comprising at least intermittently passing a regenerant containing benzene to the off-stream zone to desorb aromatic by-products from the sorbent and produce a regeneration effluent comprising benzene and aromatic by-products; d) distilling in a regeneration effluent distillation system at least a portion of the regeneration effluent to provide at least one overhead containing benzene and at least one higher-boiling fraction containing desorbed aromatic by-products; e) subjecting at least intermittently at least a portion of the at least one higher-boiling fraction to benzene-forming conditions to convert aromatic by-products to benzene and provide a conversion effluent containing benzene; f) distilling in the regeneration effluent distillation system at least a portion of the conversion effluent; g) alkylating benzene with at least a portion of the sorption effluent stream under alkylation conditions including a stoichiometric excess of benzene to provide an alkylation effluent comprising the alkylbenzene, the paraffin and benzene; and h) passing at least intermittently at least a portion of the at least one overhead containing benzene from step d to step g.