Patent ID: 7166752

Claim:
A method for decomposing a cumene oxidation product containing cumene, cumene hydroperoxide (CHP) and dimethylphenyl carbinol (DMPC) to produce phenol, acetone and alpha-methyl styrene (AMS), comprising the steps of: providing a first reaction mixture including cumene oxidation product, an acid catalyst, an acetone solution, in an amount such that 10 to 100 percent acetone relative to the amount of acetone produced during the decomposition reaction is added to the reaction mixture, and optionally water, said water being added in a stream having an adjustable feed rate; reacting the reaction mixture in a first reactor at a first average temperature to produce phenol and acetone and wherein said DMPC is converted to dicumyl peroxide (DCP); reacting the reaction mixture in a second reactor under plug-flow conditions at a second average temperature for a time sufficient to decompose the DCP into AMS and water to form a product mixture; recovering said acetone solution from the product mixture; recycling said acetone solution from the product mixture to the first reactor; monitoring the content of the acetone solution by on-line analysis; and adjusting the feed rate of the water in response to the content of the acetone solution; wherein said first average temperature is between about 50° C. and 90° C. and said second average temperature is greater than said first average temperature, provided that said second average temperature does not exceed 150° C.