The present work is continuation of our investigations on heap leaching, suggested for the first time. Various variants of alkaline leaching of alunite from alunite ore without preliminary roasting have been studied. In present work  the parameters of heap and tank alkaline leaching of alunite ore have been determined. The proposed methods can also be used to extract aluminum from poor alunite rocks. At alunite was washed 17 times with 3% NaOH solution, the degree of weight loss was 30.65%, while with 14 times washing with 10% alkali solution, the weight loss was 47.82 %. The results obtained are also typical for percolation leaching. An increase in alkali concentration and temperature intensifies the leaching process. At a ratio of solid and liquid phases of 1:5, a stirring speed of – 700 cycles/min, and an alkali concentration of 110.9 g/l, at 80⁰C within 60 minutes’ alunite dissolves up to 96% and goes into solution with accompanying components

doi.org/10.32737/0005-2531-2021-2-42-49