EVALUATION OF LEACHING CONDITIONS FOR DISSOLUTION OF PYRITE IN CHLORINE-SATURATED WATER

The optimum leaching conditions for the dissolution of pyrite in water saturated with chlorine gas were investigated. Reaction temperature, solid-to-liquid ratio, reaction time, and particle size were selected as the leaching parameters. 2ⁿ factorial experimental design and orthogonal central-composite design methods were used. A mechanical stirring speed of 500 rpm and chlorine gas-flow rate of 1379 mL/minute were chosen as the fixed parameters in all experiments. The degrees of effectiveness from high to low were found to be, in respective order, the particle size, the reaction temperature, the solid-to-liquid ratio, and leaching time. A reaction temperature of 30°C, solid-to-liquid ratio of 0.167 g/mL, particle size of 150–212 μm, and reaction time of 360 minutes were found to be the optimum leaching conditions. The dissolution yield of iron from pyrite was 98.4% under optimal leaching conditions.