Abstract
The potential use of kaolin as a lining material for the storage of acidic and acidic fluoride wastes is investigated, No significant changes are observed gravimetrically or structurally for kaolin soaked under acidic conditions down to pH 2 for periods up to 90 days, Some release of aluminium was noted with decreasing pH, Severe kaolin dissolution was apparent, however, when soaked in solutions less than pH 3 to 4 with a fluoride concentration of 0.05 M. Aluminium-oxygen bonding in kaolin appears to be substantially more prone to hydrofluoric acid attack than does silicon-oxygen bonding, resulting in a preferential release of aluminium over silicon into solution. The solution pH was found to decrease with the dissolution reaction as fluorosilicic acid was produced during the kaolin breakdown.
Original language | English |
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Journal | Soil Science |
Volume | 162 |
Issue number | 12 |
Pages (from-to) | 896-911 |
Number of pages | 16 |
ISSN | 0038-075X |
DOIs | |
Publication status | Published - 1997 |