Patent ID: 7045664

Claim:
A process for producing bisphenol A which comprises crystallizing an adduct of bisphenol A with phenol from a solution of bisphenol A in phenol to form a slurry, said bisphenol A being produced by reacting phenol and acetone in the presence of an acid catalyst, subjecting the resultant slurry to a solid-liquid separation treatment, and thereafter removing the phenol from solid components, characterized by pouring onto a filter, a slurry solution of bisphenol A in phenol, said slurry solution containing in a crystalline state, an adduct of bisphenol A with phenol having an average particle size in the range of 0.05 to 1 mm, and filtering said slurry solution under reduced pressure in an atmosphere of an inert gas stream at 30 to 80° C. containing oxygen in a concentration of at most 5,000 ppm by volume to constitute an adduct layer of bisphenol A with phenol.