Chiyoda Corporation

Tetsuo Maejima

Sachio Asaoka

Noriyuki Yoneda

Kouji Sakashita

Makoto Yasui

Hiroaki Nishijima

Nobuo Moriya

Nobuhiro Onda

Akio Shindo

Tsuneo Watanabe

Ryuichi Inaba

Takashi Imazeki

Athumi Kukidome

Kaoru Shimogawara

Yoshimi Shiroto

Kazuhiko Hamato

Keiji Shimoda

Takeshi Kouzaki

Takao Kameda

Karou Shimogawara

Athumi Kukudome

A high quality bisphenol A with a high purity and an excellent hue is produced from a crystalline adduct of bisphenol A and phenol by washing the adduct with specifically purified phenol, followed by decomposition of the washed adduct to separate bisphenol A. The purification is performed by a method including contacting raw material phenol with a strong-acid ion exchange resin to obtain treated phenol, and distilling the treated phenol.

Process for the production of bisphenol A

High quality bisphenol A is produced from a neutral crystalline adduct of bisphenol A and phenol by fusing the adduct in an atmosphere having a maximum oxygen content of 0.005 % by volume, followed by evaporation of liberated phenol. The crystalline adduct may be mixed with an aliphatic carboxylic acid before the fusion to reduce the coloring of the product. When an acidic crystalline adduct is used, the use of a strong alkali salt of an aliphatic carboxylic acid is suitably used. Interior surfaces of the apparatuses for carrying out the fusion and evaporation are desirably washed with an organic solvent to remove oxygen therefrom. The evaporation of phenol is suitably performed by two stage steam stripping wherein a used stripping gas obtained in the second stage is employed as a stripping gas in the first stage while steam is used as the stripping gas in the second stage.

Process for the production of bishenol A

High quality bisphenol A is produced from a neutral crystalline adduct of bisphenol A and phenol by fusing the adduct in an atmosphere having a maximum oxygen content of 0.005% by volume, followed by evaporation of liberated phenol. The crystalline adduct may be mixed with an aliphatic carboxylic acid before the fusion to reduce the coloring of the product. When an acidic crystalline adduct is used, the use of a strong alkali salt of an aliphatic carboxylic acid is suitably used. Interior surfaces of the apparatuses for carrying out the fusion and evaporation are desirably washed with an organic solvent to remove oxygen therefrom. The evaporation of phenol is suitably performed by two stage steam stripping wherein a used stripping gas obtained in the second stage is employed as a stripping gas in the first stage while steam is used as the stripping gas in the second stage.

High purity, crystalline adduct of bisphenol A and phenol is produced multi-stage crystallization of a phenolic slurry of bisphenol A with a crystal separation and washing step being interposed between each of the two stages. Each of the crystallization stage includes a series of crystallization towers operated at decreasing temperatures. The crystallization of the slurry is performed by continuously discharging a portion of the slurry from each of the crystallization towers, introducing the discharged slurry into one or more coolers and then recycling the cooled slurry to the tower. Another portion of the slurry in each crystallization slurry is continuously discharged, heated for dissolving fine crystals of the adduct and then recycled to the crystallization tower so that large crystals are grown in each of the crystallization steps. An apparatus having a plurality of coolers and suitable for effecting the above crystallization is also disclosed.

Process for the production of crystalline adduct of bisphenol A and

A liquid feed containing methanol, carbon monoxide, an alkyl iodide and a solvent is contacted with a supported rhodium catalyst to produce acetic acid at a temperature of 140.degree.-250.degree. C. and a pressure of 15-60 kg/cm.sup.2 G with a partial pressure of carbon monoxide of 7-30 kg/cm.sup.2 while maintaining (a) the water concentration of the product solution in the range of 0.5-10% by weight and (b) the carbonylation degree C.sub.r, defined in the specification, of the solution within the reactor at 0.15 or more. The solvent may be a carboxylic acid or a carboxylic acid ester.

Process for the production of acetic acid from methanol and carbon

Process for the production of bisphenol A.

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Tokyo, Japan

Tetsuo Maejima