Process for the production of alkylbenzene

A process for the production of alkylbenzene comprising the steps of:

• a) introducing benzene and an olefin feed into a first alkylation reaction zone in the presence of a first alkylation catalyst under first alkylation reaction conditions to produce a first alkylation effluent containing alkylbenzene and a first alkylation overhead stream;
• b) separating the first alkylation overhead stream into a liquid portion containing benzene and a vapor portion containing unconverted olefin;
• c) absorbing a major portion of the unconverted olefin in the vapor portion of the first alkylation overhead stream into an aromatic lean oil stream containing benzene and alkylbenzene in an absorption zone to produce an olefin-containing rich oil stream;
• and,
• d) introducing said rich oil stream into a second alkylation reaction zone containing a second alkylation catalyst under second alkylation reaction conditions to produce the aromatic lean oil stream, at least a portion of the aromatic lean oil stream being cycled back to the absorption zone.