氧化钼/CPC界面吸附层结构对浮选行为的影响

Influence of adsorbed layer structure of CPC/molybdite interface on flotation

通过Zeta电位测试、吸附量测量、荧光探针及单矿物浮选研究氯化十六烷基吡啶(CPC)在氧化钼表面吸附过程及吸附层结构和其对矿物浮选行为的影响。研究结果表明:氧化钼在水溶液中的等电点为1.9,在pH 2~12之内荷负电,吡啶阳离子依靠静电作用及疏水缔合作用吸附;CPC的临界胶束浓度(CMC)为9.6×10^(-4) mol/L,吡啶阳离子与氧化钼表面的吸附作用符合"四区域模型",在吡啶捕收剂浓度低于临界半胶束浓度(CHC,约6.4×10^(-4) mol/L)时,主要靠静电作用吸附,之后碳链间的疏水缔合起主要作用,且CPC浓度在CHC附近时矿物表面疏水性最强。当吡啶捕收剂浓度过大时确实会导致矿物浮选回收率的下降,临界浓度十分接近吡啶捕收剂CHC。

The adsorbed layer structure of CPC/molybdite interface and its effect on flotation were studied through Zetapotential measurements,adsorbed amount tests,fluorescence probe and micro-flotation.The results show that the IEP ofmolybdite is1.9and it is negative charged in pH range of2?12.The adsorption of CPC depends on molybdite byelectrostatic force and hydrophobic force.A CMC value of9.6×10?4mol/L is obtained by adsorption isotherm,and thefour region model is suitable for the adsorption of CPC on molybdite.When the CPC concentration is below CHC,theelectrostatic force is the reason for adsorption between CPC and molybdite,while hydrophobic force is responsible forthe adsorption at the CPC concentration over CHC.The greatest hydrophobicity is achieved around CHC.Mineralrecovery declines when the collector concentration surpasses its CHC.