The Study on Alkali Fusion-water Leaching of Silicon From Molybdenum Tailings

Abstract

Taking the molybdenum tailings produced after beneficiation of the Luanchuan molybdenum mine in Henan Province as the research object, the effects of alkali ore ratio, calcination time and calcination temperature on the activation effect of molybdenum tailings, and the effects of leaching time, leaching temperature and leaching liquid-solid ratio on the silicon leaching rate were investigated by using sodium hydroxide alkali melting-water leaching process. The results show that the optimal conditions for activation are as follows: alkali-ore ratio 1.2:1, calcination time 1 h, calcination temperature 700°C. Under these conditions, the concentration of alkali fusion leaching (Si+Al) of molybdenum tailings is 1.396 mg/L. The optimum conditions for leaching are as follows: leaching time 7 h, leaching temperature 45°C, leaching liquid-solid ratio 6: 1. Under these conditions, the leaching rate of silicon can reach 26.88%. During the calcination process, the crystal structure of quartz is destroyed, and sodium hydroxide reacts with quartz at high temperature to form soluble silicate, which improves the activity of molybdenum tailings and increases the dissolution of silicon