Alkylation-transalkylation process using stripping to produce a dry transalkylation feed

A process for the production of cumene which comprises:

• (a) contacting a benzene feed and a propylene feed with an alkylation catalyst comprising beta zeolite in an alkylation zone at alkylation conditions comprising a liquid phase, a temperature of from 302.degree. to 518.degree. F., a pressure of from 150 to 2000 psi(g), and a water concentration of at least 30 wppm, reacting benzene and propylene to produce cumene in said alkylation zone, and recovering from said alkylation zone an alkylation reaction zone effluent comprising benzene, cumene, diisopropylbenzene, heavier alkylated aromatic hydrocarbons, and water;
• (b) passing said alkylation reaction zone effluent to a stripping column, removing water from said alkylation reaction zone effluent in said stripping column, withdrawing as a bottom stream of said stripping column a stripped alkylation reaction zone effluent comprising benzene, cumene, diisopropylbenzene, and said heavier alkylated aromatic hydrocarbons, and containing less than 10 mol-% of the water and less than 73 mol-% of the benzene in said alkylation reaction zone effluent;
• (c) passing said stripped alkylation reaction zone effluent and a transalkylation reaction zone effluent comprising cumene to a first fractionation column, separating said hydrocarbons in said first fractionation column into an alkylate stream comprising cumene, diisopropylbenzene, and said heavier alkylated aromatic hydrocarbons, and a first recycle stream comprising benzene, and withdrawing said alkylate stream and said first recycle stream from said first fractionation column;
• (d) passing at least a portion of said first recycle stream to said alkylation zone;
• (e) passing said alkylate stream to a second fractionation column, separating said hydrocarbons in said second fractionation column into an intermediate separation stream comprising said diisopropylbenzene and said heavier aromatic hydrocarbons and a product stream comprising cumene, and withdrawing said intermediate separation stream and said product stream from said second fractionation column;
• (f) passing said intermediate separation stream to a third fractionation column, separating said hydrocarbons in said third fractionation column into a second recycle stream comprising diisopropylbenzene and a heavy aromatic stream comprising said heavier alkylated aromatic hydrocarbons, and withdrawing said second recycle stream and said heavy aromatic stream from said third fractionation column;
• and,
• (g) passing at least a portion of said first recycle stream and at least a portion of said second recycle stream to a transalkylation zone containing a transalkylation catalyst comprising beta zeolite at transalkylation conditions comprising a temperature of from 392.degree. to 500.degree. F., a pressure of from 150 to 2000 psi(g), and a water concentration of less than 20 wppm, reacting in said transalkylation zone benzene and diisopropylbenzene to produce cumene, and recovering from said transalkylation zone said transalkylation reaction zone effluent.