多金属金矿氢氧化钠焙烧热力学研究

Thermodynamics study of sodium hydroxide roasting in a poly-metallic gold mine

摘要: 焙烧是一种提高多金属金矿中金、银回收率的有效预处理方法, 通过热力学计算, 得到了多金属金矿NaOH焙烧过程主要化学反应的ΔG_T⁰-T函数, 并绘制了ΔG_T⁰-T图.热力学分析结果表明NaOH焙烧能降低CuO·Fe₂O₃、ZnO· Fe₂O₃、PbO· SiO₂、2ZnO·SiO₂的生成几率, 从而降低了以上物质对Au、Ag的包裹作用.多金属金矿NaOH焙烧的适宜温度为T≥834.33 K.

Abstract: Roasting is an effective pre-treatment technology to improve gold and silver recovery rate for poly-metallic gold mine. ΔG_T⁰-T function of the main chemical reaction during NaOH roasting process in the poly-metallic gold mine by thermodynamic calculations. ΔG_T⁰-T is drawn accordingly. Thermodynamics calculation results show that NaOH roasting lowers the generating chances of copper ferrite, zinc ferrite, zinc silicate and lead silicate, whose binding forces to Au and Ag decreases accordingly. The appropriate temperature of roasting sodium hydroxide is higher than 834.33 K.