Chiyoda Corporation

Nippon Steel Chemical Co., Ltd.

Nobuo Moriya

Sachio Asaoka

Kouji Sakashita

Hiroaki Nishijima

Nobuhiro Onda

Tetsuo Maejima

Makoto Yasui

Tsuneo Watanabe

Noriyuki Yoneda

Akio Shindo

Ryuichi Inaba

Takashi Imazeki

Athumi Kukidome

Keiji Shimoda

Kaoru Shimogawara

Susumu Yamamoto

Katsuhiko Sakura

Takeshi Kouzaki

Toshihiko Furukawa

Nobuyuki Suda

Yasumasa Morita

Hiroshi Yagi

Makoto Nomura

Takao Kameda

Ryosuke Shimizu

Nobuaki Egashira

Athumi Kukudome

Takao Kawai

Karou Shimogawara

Kiyoshi Hashimoto

Hiroshi Yanai

Tadayoshi Matsuo

Tsohikazu Maruyama

Yoshiaki Matsui

Masanori Nagase

Takamasa Minami

A reformed gas composed mainly of hydrogen and carbon monoxide to be used for a fuel cell is produced by using a multi-tubular reformer provided with bayonet type double-wall catalyst tubes and feeding hydrocarbon gas such as natural gas and steam to the reformer. Porous media of a ceramic material are arranged in such a manner in a shell side flue gas inlet part of the interior of the reformer as to envelop the leading end parts of the catalyst tubes. The transfer of heat from the flue gas to the catalyst tubes is enhanced because the porous media accumulate the heat from the flue gas and radiate the accumulated heat in the direction of the walls of the outer tubes of the catalyst tubes. The otherwise possible uneven transfer of heat to the catalyst tubes is prevented because the wall effect and the channelling of the flue gas are repressed. This invention, therefore, permits effective utilization of the thermal energy of the flue gas for the reforming reaction and enables the reformer to be stably operated.

Method of heat transfer in reformer

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.

Process for the production of 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

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

Process for the production of 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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Yokohama, Japan

Nobuo Moriya