| 摘要 |
<p>The invention relates to a process for removal of impurities from secondary aluminia fines and alumina and/or fluorine containing materiel comprising. (a) acidification by adding an acid (2,12, 32) to the material to be purified (1,11,31); (b) heating the acidified mixture (3,13,35) ; (c) leaching the mixture in a solution of an acid (6,16,39) ; (d) separating the solid and liquid.</p> |
