Study on Iron Species Transformation in the Leaching of Copper Concentrate by H2SO4-Fe2(SO4)3
The H2SO4-Fe2(SO4)3 leaching system is widely used for the leaching of copper concentrate due to its low cost and low corrosivity.The species change of iron in solution determine the economic benefits of the leaching process.This study investigates the iron species in the leach solution under different conditions on a basis of the process.It has been shown that the conversion between Fe3+ and Fe2+ mainly involves electron transfer and does not alter the H+ concentration.When the pH value of the leach solution rises to 2,a large amount of jarosite will be generated,with Cu of a mass fraction of 1.0% and Zn of a mass fraction of 0.5%.When the concentration of Fe2+ in the leach solution exceeds 46.5 g/L,heptahydrated ferrous sulphate crystals will be generated at room temperature,with Cu of a mass fraction of 1.9% and Zn of a mass fraction of 1.0%.