Patent · US Expired

Color removal process

US4089780A · kind A · utility

13Cited by
4References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 6, 1976
Grant dateMay 16, 1978
Priority date
Expiry dateAug 6, 1996

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S210/917
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

Color is removed from paper mill waste waters by treatment with a cationic water soluble polyamine having an average molecular weight of at least 300 at a pH of 2 to 5, preferably 2.5 to 3.5, followed by precipitation with a water soluble anionic or non-ionic organic polymer having an average molecular weight of at least 10,000.

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