Patent · US Expired

Method of producing carboxymethyloxysuccinic acid

US3948985A · kind A · utility

2Cited by
4References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 11, 1974
Grant dateApr 6, 1976
Priority date
Expiry dateOct 11, 1994

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C51/367
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Carboxymethyloxysuccinic acid is prepared by acidifying the calcium salt of carboxymethyloxysuccinic acid with sulfuric acid at a temperature of 40.degree.C to 80.degree.C; filtering off the CaSO.sub.4 .2H.sub.2 O by-product and concentrating the filtrate to give the purified acid. The calcium salt of carboxymethoxysuccinic acid is formed by reacting maleic acid and glycolic acid in aqueous media containing excess calcium hydroxide.

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