Patent · US Expired

Processing of kaolinitic clays at high solids

US4186027A · kind A · utility

32Cited by
18References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 30, 1978
Grant dateJan 29, 1980
Priority date
Expiry dateMay 30, 1998

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01P2006/90
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A process for treating a clay mineral of the kandite group comprising forming a fluid aqueous suspension of the clay mineral, the suspension having a solids content in the range of from 60% to 75% by weight and a pH in the range of from 7.0 to 11.0 and the suspension containing a dispersing agent to deflocculate the clay mineral; and treating the fluid suspension of clay containing the dispersing agent with a water-soluble reducing bleaching agent under alkaline pH conditions for a time sufficient to give the desired improvement in brightness of the clay. Preferably, the clay mineral suspension is subjected to a particle size separation process at said solids content to reduce the percentage of particles larger than 10.mu.m to not more than 3% by weight. Advantageously, the viscosity of the clay mineral suspension during the particle size separation process is below 2 poise.

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