Patent · US Expired

Sulfonation of anthraquinone in sulfur dioxide solvent

US4124606A · kind A · utility

9Cited by
5References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 8, 1976
Grant dateNov 7, 1978
Priority date
Expiry dateDec 8, 1996

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C309/28
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Sulfonation of anthraquinone by a sulfur trioxide component including SO.sub.3 or oleum in a liquid sulfur dioxide solvent. When a mercury catalyst is used to give alpha anthraquinone sulfonate products, most of the mercury is left in the reactor or recovered with unreacted anthraquinone by precipitation with water after vaporization of the sulfur dioxide. High sulfuric acid and mercury pollution are thus avoided.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.