黄铜矿与孔雀石的电子结构及硫化作用的电化学研究

Electronic Structures and Electrochemical Sulfofication of Chalcopyrite and Malachite

通过电子密度计算、循环伏安测试和浮选试验等方法,分析了硫化钠在黄药浮选黄铜矿和孔雀石过程中的抑制与活化作用及机理。结果表明,黄铜矿中铜和硫原子之间有较强的电子云重叠,共价作用明显,易与黄药作用而上浮,随硫化钠浓度的增加,黄药与黄铜矿作用的循环伏安曲线上出现的氧化峰逐渐减弱以至于消失,表明硫化钠对黄药在黄铜矿表面的吸附起到了抑制作用;而孔雀石中铜和氧之间电子云重叠较少,离子键作用显著,难以与黄药直接作用,循环伏安曲线测试结果证实了黄药在硫化的孔雀石表面吸附伴随着电子转移,是一个电化学过程,在适宜的硫化钠浓度下,黄药与孔雀石作用的循环伏安曲线上出现了氧化峰,表明硫化钠能促进黄药在孔雀石表面吸附,起到活化作用。

The inhibition and activation of sodium sulfide in xanthate flotation chalcopyrite and malachite were analyzed by electron density calculation,cyclic voltammetry and flotation tests. The results show that the copper and sulphur atoms in chalcopyrite have a strong overlap of electron clouds and have a covalent effect. They tend to float with the xanthate action,and with the increase of sodium sulfide concentration,the oxidation peak appearing on the cyclic voltammetry curve of the xanthate and chalcopyrite reaction gradually weakened and disappeared,indicating that sodium sulfide can inhibit the adsorption of xanthate on the surface of chalcopyrite; while the overlapping of electron cloud between copper and oxygen in malachite is less and ion bonding is significant,it is difficult to directly interact with xanthate. The cyclic voltammetry curve test results confirm that xanthate adsorption on the surface of sulfurated malachite is accompanied by electron transfer,and it is an electrochemical process. With appropriate concentration of sodium sulfide,the oxidation peak appeared on the cyclic voltammetry curve of xanthate and malachite reaction,indicating that sodium sulfide can promote xanthate adsorption on malachite surface and play an activating role.