Nippon Steel Chemical Co., Ltd.

Chiyoda Corporation

Katsuhiko Sakura

Sachio Asaoka

Susumu Yamamoto

Nobuo Moriya

Shingo Ueda

Toshihiko Furukawa

Nobuyuki Suda

Kouji Sakashita

Genki Takeuchi

Kazuyoshi Horibe

Makoto Nomura

Keiji Shimoda

Hiroshi Yanai

Shyouta Shirasaka

Noboru Daitou

Tadayoshi Matsuo

Toshikazu Maruyama

Tsohikazu Maruyama

Yoshiaki Matsui

Taketoshi Kitoh

Masanori Nagase

Morio Kimura

Takamasa Minami

Yasuharu Hukuda

Kiyoshi Hashimoto

Nobuaki Egashira

Ryouji Akamine

High-purity benzyl benzoate is recovered by distilling the residue remaining after removal of unreacted toluene and benzoic acid from a reaction mixture produced by the oxidation of toluene by molecular oxygen in the presence of a metal catalyst thereby separating a fraction of benzyl benzoate containing 80 wt % or more benzyl benzoate, 10 wt % or less benzoic acid and 10 wt % or less fluorenone, and purifying the fraction of benzyl benzoate by crystallization such as recrystallization. According to this process, it is possible to recover high-purity benzyl benzoate by a simple operation at low cost from the by-product formed in the manufacture of benzoic acid.

Process for recovering benzyl benzoate

This invention relates to a process for preparing bisphenol A by the condensation of phenol with acetone in the presence of cation exchange resin obtained by sulfonating copolymers of monovinyl monomers mainly consisting of styrenes and divinyl monomers as crosslinking agent while using divinylbiphenyl and divinylbenzene mainly as said divinyl monomers and controlling the molar ratio of divinylbiphenyl to divinylbenzene at 10/0-2/8. The cation exchange resin to be used as catalyst in the condensation reaction shows a long life, maintains the production of bisphenol A over a long period of time, possesses high strength and is useful for economical and advantageous production of bisphenol A.

Process for preparing bisphenol A

The invention relates to a process for preparing prilled bisphenol A by granulation which comprises adding compounds soluble in molten bisphenol A, not affecting adversely the melt color of bisphenol A to any significant extent, and have a melting point of 60.degree. C. or more to bisphenol A and granulating and also to a process which comprises adding the reaction mother liquor or cyrstallization mother liquor produced in the manufacturing step of bisphenol A to bisphenol A or the adduct of bispheol A and phenol or a mixture of bispheol A and phenol, removing the phenol, and granulating. The processes yield prilled bispheol A which have high strength and resist powdering.

Process for preparing prilled bisphenol A

This invention relates to a process for preparing bisphenol A of good heat stability by heat-treating bisphenol A containing a very small amount of impurities in a molten state at 185.degree. to 220.degree. C. for 5 to 60 minutes in an oxygen-free atmosphere and the process yields bisphenol A of good heat stability which shows reduced coloration when heated. Bisphenol A prepared by this process has excellent properties relating to color and is particularly suitable as raw material for the manufacture of polycarbonates where the requirement for color is strict.

Process for preparing bisphenol A of good heat stability

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Kitakyushu, Japan

Katsuhiko Sakura