The invention discloses a method for
lepidolite defluorination and valuable
metal leaching. The method comprises the following steps that (1)
lepidolite is crushed and levigated, mineral
powder is obtained, and in the mineral
powder, the
mass of mineral
powder with the particle size smaller than 0.074 mm accounts for 70% or above of the total mineral powder
mass; (2) the mineral powder is added with concentrated sulphuric acid, the mineral powder and the concentrated sulphuric acid are uniformly mixed, and the
mass ratio of the concentrated sulphuric acid to the mineral powder is 0.8-1:1; then water is added into the mineral powder and the concentrated sulphuric acid, the
mass ratio of the water to the mineral powder is 0.08-0.1:1, the water, the mineral powder and the concentrated sulphuric acid are uniformly mixed, and mixed minerals are obtained; the mixed minerals are subjected to heat preservation and stockpiling for 20-30 h, defluorination is achieved, and curing minerals are obtained; and (3) the curing minerals are added with water to be leached out, the
mass ratio of the water to the curing minerals is 1.0-2.5:1, leaching is conducted for 2-4 h under the condition that the temperature is 90 DEG C-100 DEG C, mineral pulp is filtered, and leached
slag and leached liquid are obtained. According to the method for
lepidolite defluorination and valuable
metal leaching, stockpiling, curing and defluorination are conducted through
self heating, technological processes are simplified, the production cost is substantially reduced, and equipment investments are decreased; the curing defluorination-water leaching technology is adopted, so that the defluorination rate and the valuable
metal leaching rate are increased; and the defluorination rate is larger than 95%, and the
leaching rate of
lithium, the
leaching rate of
potassium, the leaching rate of
rubidium and the leaching rate of cesium are larger than 90%.