Idemitsu Kosan Company, Limited

Idemitsu Petrochemical Co., Ltd.

Kazuyuki Hirano

Norio Ogata

Ken Fujimoto

In a process for producing bisphenol A, an adduct of bisphenol A with phenol is promptly recovered in highly purity and high efficiency from a reaction mother liquor in the case of singling out bisphenol A from a reaction product. An adduct layer of bisphenol A with phenol is formed by crystallizing an adduct of bisphenol A with phenol from a solution of bisphenol A in phenol to form a slurry, the 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, the slurry solution containing in a crystalline state, an adduct of bisphenol A having an average particle size in the range of 0.05 to 1 mm with phenol, and filtering the slurry solution under reduced pressure in an atmosphere of an inert gas stream at 30 to 80&#xb0; C. containing oxygen in a concentration of at most 5,000 ppm by volume.

Process for producing bisphenol A

Provided is a production process for high quality bisphenol A which is reduced in a sulfonic acid-containing heavy matter contained in the product and which is improved in a hue. In an after-treating step for a reaction mixed solution obtained by condensing excess phenol with acetone in the presence of an acid catalyst, a filtering step by a filter is provided at least in one step between a step for dissolving an adduct of bisphenol A and phenol by using a phenol-containing solution and a step for crystallizing and separating the above adduct from this solution.

Growing community of inventors

Chiba, Japan

Kazuyuki Hirano