Leaching Behavior of Manganese, Iron and Aluminum in Complex Lean Manganese Ore by Pressure Leaching
Pressure leaching manganese from complex lean manganese ores was investigated using pyrite as a reducing
agent and air as pressurized gas in dilute sulfuric acid medium. The effects of pyrite amount, acid concentration,
leaching temperature, liquid/solid ratio, leaching pressure, reaction time, and Ore particle size were discussed.
The leaching rate of manganese is 98.8%, and the leaching rates of iron and aluminum are 9.25% and 15.6%,
respectively, under optimal conditions that were determined to be 100 g of manganese ore and 50 g of pyrite,
agitation speed of 500 rpm, ore size of 74 μm, sulfuric acid concentration of 120 g/L, leaching temperature of
120 C, liquid/solid ratio of 5:1, and air pressure of 0.5 MPa for 60 min. During pressure leaching, dissolved Fe
and Al were partly hydrolyzed giving lower concentrations of Fe and Al in the leach liquor to easily separate
Mn during downstream processing of the leach liquor.