Patent · US Expired

Process for the bleaching of a pulp suspension by separating calcium from lignin

US6679972B1 · kind B1 · utility

2Cited by
4References
24Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 15, 2002
Grant dateJan 20, 2004
Priority date
Expiry dateFeb 15, 2022

Classification

  • Technology area (CPC D)Textiles; Paper
  • CPC primaryD21H23/04
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

A process for the bleaching of lignin present in pulp fibers in an aqueous environment such as a pulp suspension. The invention also relates to a process for producing paper or board from pulp containing bleached lignin. According to the invention carbon dioxide is used for the bleaching of lignin.

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