Leaching Pyrolusite Ore by Sulfur Dioxide

Reaction kinetics for leaching Pyrolusite ore (Mn content 25%,) by pure SO2gas is discussed. Based on determining the effects of temperature, ore particle size, flow ofSO2, liquid/solid ratio, and stirring rate on manganese leaching rate, the kinetic equation isconcluded as follows:The experimental results show that the leaching process is controlled by the chemical reaction atthe mineral surface. The leaching reaction can be carried oat easily at atmospheric temperature.At the same time, the behavior of Fe in Pyrolusite ore is investigated and the catalysis of ferrousion confirmed. The grade of crystal manganese sulfate MnSO4.H2O obtained after removingthe impurities in leaching liquid, evaporating and concentrating the purified leaching liquidsatisfies GB8213-87.