研究一种新型结构的双硫脲表面活性剂——N,N′-二异丙氧基丙基-N″,N′′′-氧二乙氧羰基硫脲(Di PODECTU)在黄铜矿表面的吸附动力学和热力学。研究结果表明:黄铜矿吸附Di PODECTU较佳的p H范围为5~10,吸附量随着温度的升高而减小。等温吸附模型符合Langmuir模型,其吸附焓变ΔH为-19.56 k J/mol,吸附自由能变ΔG为-28.70 k J/mol(298 K),说明Di PODECTU在黄铜矿表面为单层化学吸附。吸附过程符合二级动力学方程,吸附速率常数Ks为0.144 m-2/(mol·h),平衡吸附量Qe为5.72×10^-5 mol/m2,与实测值5.41×10^-5 mol/m2接近。Di PODECTU主要以化学作用方式吸附在黄铜矿表面。
A novel surfactant, N, N′-dipropoxypropyl-N″, N′′′-oxydiethylenedicarbonyl bis(thiourea)(Di PODECTU) was introduced, and its adsorption kinetics and thermodynamics with chalcopyrite were investigated. The results indicate that the recommended p Hs for Di PODECTU adsorbing on chalcopyrite surface are 5-10 and the adsorption decreases with the increase of temperature. The isothermal adsorption model conforms to Langmuir model, and the adsorption enthalpy change and free energy change are-19.56 k J/mol and-28.70 k J/mol(298 K), respectively, which demonstrates that Di PODECTU adsorbes on chalcopyrite surface mainly through monolayer chemisorption. The adsorption process conforms to second-order kinetics equation and the adsorption rate constant is 0.144 m-2/(mol·h). The calculated equilibrium adsorption Qe(5.72×10^-5 mol/m2) is close to the experimental value Qe(5.41×10^-5 mol/m2). Di PODECTU adsorbs on chalcopyrite surface mainly through chemisorption.