Back to results
US 4,061,646 AGranted
Process for purification of crude 2-mercaptobenzothiazole
AssigneeSanshin Kagaku Kogyo Co., Ltd.
InventorsYutaka Kawaoka, Tatsuo Kifune, Masahiko Teshima, Tatsuya Koizumi
Life of this patent
Estimating the term…
Abstract
Crude 2-mercaptobenzothiazole is purified by preparing a crude, liquid 2-mercaptobenzothiazole by reacting aniline, carbon disulfide and sulfur under elevated pressure at high temperatures; extracting said crude, liquid 2-mercaptobenzothiazole in the molten state with cold carbon disulfide by liquid-liquid extraction thereby forming a slurry of 2-mercaptobenzothiazole crystals; and filtering and drying said crystals.
Claims6
A process for purifying crude 2-mercaptobenzothiazole, which comprises:
- preparing a crude, molten 2-mercaptobenzothiazole by reacting aniline, carbon disulfide and sulfur under elevated pressure at high temperatures;
- immediately quenching said molten, crude 2-mercaptobenzothiazole after its preparation by pouring said molten, crude 2-mercaptobenzothiazole into cold carbon disulfide thereby forming a slurry of 2-mercaptobenzothiazole crystals;
- and
- filtering and drying said crystals of 2-mercaptobenzothiazole.
1 more element
Dependencies are inferred from the claim text.