To reduce the environmental impact caused by highly toxic dichromate in flotation separation of copper-lead sulfide, the replacement of dichromate with depressants mixture (humic substance and hydrogen peroxide) was investigated in this paper. The single mineral flotation and the mixed binary minerals experiment at pH 6.5 showed that combined depressants could be efficient in separating galena from chalcopyrite and achieve a lead concentrate comparable to conventional method using dichromate as typical depressant. The contact angle measurement and atomic force microscopy (AFM) imaging indicated that, for the same concentration of sodium humate, the treatment by hydrogen peroxide could increase surface wettability and largely enhance chemical adsorption of humate on galena surface. Ion dissolution tests and adsorption tests indicated that the hydrogen peroxide can accelerate dissolution of galena lattice and the hydrogen peroxide or Pb²⁺ could promote the adsorption of NaHA on the surface of galena.

为减少硫化铜铅浮选分离过程中剧毒重铬酸盐对环境的影响，本文研究了用抑制剂混合物（腐殖质和过氧化氢）代替重铬酸盐。pH 6.5 的单一矿物浮选和混合二元矿物实验表明，组合抑制剂可以有效地从黄铜矿中分离方铅矿，并获得与使用重铬酸盐作为典型抑制剂的常规方法相当的铅精矿。接触角测量和原子力显微镜（AFM）成像表明，对于相同浓度的腐植酸钠，过氧化氢处理可以增加表面润湿性并大大增强腐植酸盐在方铅矿表面的化学吸附。²⁺可以促进NaHA在方铅矿表面的吸附。