US 6,186,335 B1 · Process for beneficiating kaolin clays

Abstract

A improved process for beneficiating kaolin clays to remove discoloring impurities is disclosed. The beneficiation of kaolin clay is improved by fractionating a kaolin clay starting material into a lower brightness first fraction having a majority of the discoloring impurities and a higher brightness second fraction with less impurities. The first fraction is then beneficiated (such as by flotation, selection flocculation, high intensity magnetic separation and/or leaching) to produce a kaolin clay product with improved optical properties. The first and second fractions may be combined to produce a product with improved optical properties.

Claims28

Dependent claims

A process for the beneficiation of a kaolin clay material, wherein the process comprises the sequential steps of:

A. obtaining a dispersed aqueous slurry of a kaolin clay starting material which contains discoloring impurities;
B. fractionating the aqueous slurry into a first fraction having a majority of the discoloring impurities and a second fraction having a minority of the discoloring impurities;
and
C. beneficiating the first fraction to remove the discoloring impurities and produce a kaolin clay product,
wherein the optical properties of the kaolin clay product are improved over the optical properties of the kaolin clay starting material and wherein the process is conducted in the absence of grinding.

2 more elements

Dependencies are inferred from the claim text.

Process for beneficiating kaolin clays

Life of this patent

Process for beneficiating kaolin clays

Life of this patent

Abstract

Claims28