Method for improving the brightness of kaolin clay
Abstract
Abstract An improved process for improving the brightness of impure kaolin clay containing discrete colored particles of titaniferous impurities wherein the impurities are selectively floated from a dispersed slip of the clay by quiescent (rather than by dynamic) means and the purified clay is further brightened by treatment with a reducing bleach reagent such as zinc hydrosulfite. In carrying out such process, the time required for conditioning the slip of impure clay with an anionic reagent selective to the colored impurities, and consequently the power demand required to obtain a product of desired quality by quiescent flotation, are reduced significantly by subjecting the slip of beneficiated clay, after quiescent flotation of colored impurities, to a mild oxidation treatment before bleaching the purified clay.
Inventors
- 👤 Miller B Mallary
- 👤 Joseph L Hunter
Bibliographic Details
Claims Analysis
Total Claims: 3References Cited (Backward Citations)
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