以铁闪锌矿单矿物、黄铜矿单矿物、氰化铁闪锌矿和氰化黄铜矿为研究对象,研究焦亚硫酸钠活化氰化硫化铜锌矿的活化浮选动力学。结果表明:在丁基黄药5.32×10^-5 mol/L、2号油10 mg/L、硫酸铜8.01×10^-5 mol/L、p H 9.8~10.2、焦亚硫酸钠添加量1.67×10^-5 mol/L的条件下,锌回收率达到86%以上;在丁基黄药5.32×10^-5 mol/L、2号油10 mg/L、p H 9.8~10.2,焦亚硫酸钠添加量1.33×10^-5 mol/L的条件下,铜回收率达到95%以上;与氰化铁闪锌矿相比,焦亚硫酸钠活化氰化黄铜矿的速率常数相对较高。在此基础上,通过红外光谱和Zeta电位对活化机理进行分析,表明在溶液中焦亚硫酸钠水解生成的SO3^2-能够将CN^-氧化为CNO^-,破坏Zn(CN)4^2-和Cu(CN)2^-中的Zn—C和Cu—C键,阻碍CN-在矿物表面的吸附;同时SO3^2-也可以将S^2-氧化为单质硫,形成疏水性矿物表面。在活化过程中,由于CN^-的还原性强于S^2-的,焦亚硫酸钠优先与CN-发生反应。
The activation of depressed marmatite and chalcopyrite were investigated using sodium metabisulfite as activator. The results indicate that the zinc recovery rate exceeds 86% under the conditions of xanthate concentration of 5.32×10^-5 mol/L, 2# oil 10 mg/L, copper sulfate concentration 8.01×10^-5 mol/L, p H of 9.8-10.2 and sodium metabisulfite concentration of 1.67×10^-3 mol/L. The copper recovery rate exceeds 95% under the conditions of xanthate concentration of 5.32×10^-5 mol/L, 2^# oil of 10 mg/L, p H of 9.8-10.2 and sodium metabisulfite concentration of 1.33×10^-3 mol/L. Moreover, the activation-flotation rate constant of chalcopyrite is bigger than that of marmatite. Based on above studies, IR and Zeta potential were used to analyze the activation mechanism. The results show that the ion SO3^2-, which sodium metabisulfite can give in aqueous solutions, can promote the oxidation of cyanide to cyanate, and therefore destroy Zn—C bond and Cu—C bond, which inhibites the adsorption of cyanide. Moreover, the ion SO3^2- can oxidize divalent sulfur ion into elemental sulfur, causing the mineral surfaces hydrophobic. Due to stronger reducibility of cyanide than that of divalent sulfur ion, sodium metabisulfite can firstly destroy cyanide and then attack the sulphides.