Selective depression of copper-activated sphalerite by polyaspartic acid during chalcopyrite flotation

聚天冬氨酸在黄铜矿浮选体系中对铜离子活化后的闪锌矿的选择性抑制作用

Environmentally friendly flotation reagent,polyaspartic acid(PAPA),was tested as a potential selective depressant in the flotation separation of chalcopyrite and Cu-activated sphalerite.The depression mechanism of PAPA was revealed by contact angle measurements,Zeta potential measurements,Fourier transform infrared spectroscopy(FT-IR)analysis and inductively coupled plasma(ICP)measurement.The micro-flotation tests with single minerals showed that PAPA selectively depressed Cu-activated sphalerite,while chalcopyrite remained floatable.Moreover,a concentrate containing 31.40%Cu with a recovery of 92.43%was obtained in flotation tests of artificially mixed minerals.Results of contact angle measurements,Zeta potential measurements and FT-IR spectrum revealed that PAPA exerted a much stronger adsorption on Cu-activated sphalerite surface than on chalcopyrite surface,preventing the further adsorption of sodium diethyl dithiocarbamate(DDTC)on its surface.ICP measurements indicated that PAPA had an excellent complexing ability with Cu^(2+)in flotation pulp,weakening the activation of Cu species on sphalerite surface and producing selective depression.

采用环保型的浮选药剂聚天冬氨酸(PAPA)作抑制剂,进行黄铜矿和铜活化后闪锌矿的浮选分离。通过接触角测试、动电位测试、红外光谱分析和电感耦合等离子体发射光谱测试,研究PAPA对闪锌矿的选择性抑制机理。单矿物浮选试验结果表明,PAPA能选择性抑制铜活化后的闪锌矿,但黄铜矿仍能保持好的可浮性。人工混合矿浮选试验获得铜精矿中铜品位为31.40%,铜回收率为92.43%。接触角测试、动电位试验和红外光谱分析表明,PAPA在铜活化后的闪锌矿表面吸附更强;另外,PAPA的存在能阻止铜活化后的闪锌矿表面捕收剂二乙基二硫代氨基甲酸钠(DDTC)的进一步吸附。电感耦合等离子体发射光谱测试结果表明,PAPA对铜离子有较强的络合能力,能减弱闪锌矿表面铜离子的活化,从而产生选择性抑制。