Sumitomo Chemical Company, Limited

Norio Kotera

Yuzo Maegawa

Tatsuo Kaneoya

Shinzaburo Masaki

Takashi Miyaoka

Masatoshi Uegaki

Kenji Tanimoto

Masakatsu Yoshimura

Kazuhiro Tada

Hiroshi Yoshitake

Akira Fukasawa

Hiromichi Okabe

Hiroshi Korenaga

Masatoshi Takahashi

Kunihisa Goto

A method for purifying 1-aminoanthraquinone which comprises previously subjecting a crude 1-aminoanthraquinone to a removal treatment of inorganic impurities so that their content is reduced to not more than 4 wt. % as converted to ash basis or to a removal treatment of iodine-consuming reductive inorganic impurities so that their content is reduced to not more than 2 wt. % as converted to consumed iodine basis, and then rectifying the 1-aminoanthraquinone.

Method for purifying 1-aminoanthraquinone

A process for producing aminophenyl-.beta.-hydroxyethylsulfone of the formula (I), ##STR1## which comprises the following steps: (1) condensing nitrohalobenzene with mercaptoethanol in the presence of an alkali hydroxide and at least one reaction medium selected from N-alkyl-substituted amides and sulfoxides to produce mononitrophenyl-.beta.-hydroxyethylsulfide of the formula (II): ##STR2## (2) oxidizing the mononitrophenyl-.beta.-hydroxyethylsulfide (II) to produce mononitrophenyl-.beta.-hydroxyethylsulfone of the formula (III): ##STR3## and (3) reducing the mononitrophenyl-.beta.-hydroxyethylsulfone to produce the aminophenyl-.beta.-hydroxyethylsulfone of the formula (I). This compound is useful as an intermediate for aminophenyl-.beta.-sulfatoethylsulfone represented by the following formula: ##STR4## which is an important intermediate for vinyl sulfone type reactive dyes largely used for dyeing cellulose fiber materials.

Process for producing aminophenyl-.beta.-hydroxyethylsulfone

A high melting, high boiling organic compound is easily and stably purified by continuously supplying the molten organic compound to a rectification zone under a subatmospheric pressure and continuously distilling off and recovering vapors from the top of the rectification zone, while continuously withdrawing bottoms containing higher boiling impurities and/or involatile impurities than the desired compound from a reboiling zone at the bottom of the rectification zone to the outside of rectification system by means of a barometric leg, without any pretreatment of removing lower boiling impurities therefrom before the rectification, and without disturbing a pressure balance in the rectification system.

Purification of compounds having high melting point

In a process for producing 8-amino-1-naphthol-3,6-disulfonic acid which comprises subjecting a 1-nitronaphthalene-3,6,8-trisulfonic acid reaction mixture to reduction, subjecting the resulting 1-naphthylamine-3,6,8-trisulfonic acid salt mixture to alkali fusion and subjecting the alkali fusion mixture to precipitation by mixing with an acid to obtain 8-amino-1-naphthol-3,6-disulfonic acid as a partial alkali metal salt, the amount of acids and bases used can be curtailed and the quality of the product can be improved by performing the precipitation by mixing said alkali fusion mixture with said 1-nitronaphthalene-3,6,8-trisulfonic acid reaction mixture, separating the precipitated partial alkali metal salt of 8-amino-1-naphthol-3,6-disulfonic acid by filtration, and using as a starting material for said reduction reaction the resulting filtrate containing 1-nitronaphthalene-3,6,8-trisulfonic acid and/or a salt thereof.

Process for producing 8-amino-1-naphthol-3,6-disulfonic acid

An aluminum halide complex of an aluminum halide, a hydrogen halide and an alkylbenzene is prepared by continuously feeding a gaseous hydrogen halide to a reaction zone comprising aluminum and an alkylbenzene and continuously taking the resulting aluminum halide complex out of the reaction zone, the byproduced hydrogen gas being taken out of the reaction zone, and aluminum and the alkylbenzene being fed continuously or intermittently to the reaction zone.

Aluminum catalysts

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Amagasaki, Japan

Norio Kotera