Process for the production of alkylbenzene with ethane stripping

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 and ethane;
• c) absorbing a major portion of the unconverted olefin in the vapor portion of the first alkylation overhead stream into a de-ethanized aromatic substantially olefin-free lean oil stream containing benzene and alkylbenzene in an absorption zone to produce a rich oil stream containing olefins and at least some of the ethane;
• d) introducing said rich oil stream into a second alkylation reaction zone containing a second alkylation catalyst under second alkylation reaction conditions to produce a first aromatic lean oil stream;
• and,
• e) fractionating the first aromatic lean oil stream in a de-ethanizer to produces a de-ethanizer vapor overhead containing a major portion of the ethane and a liquid bottoms stream containing the de-ethanized aromatic lean oil.