| 摘要 |
<p>A process for purification of coal comprises forming an aqueous leaching solution containing nitric and hydrofluoric acid. Impurities are removed by contacting coal having a mesh size not greater than 8 (Tyler Series) with the leaching solution for a period of 15 to 120 minutes at a temperature of 20 to 100.degree.C. During the contacting of coal with leaching solution, a gaseous material such as air can be bubbled therethrough to provide additional mixing action and oxidant material. Thereafter, the solution is removed and the leached coal washed with water.</p> |
