光谱电化学研究乙硫氮与脆硫锑铅矿的作用机制

Study on Mechanism of Diethyldithiocarbamate with Jamesonite by Spectroelectro-chemistry

采用光谱分析及恒电位阶跃法，研究了乙硫氮在脆硫锑铅矿表面吸附的光谱电化学行为及作用机理。结果表明其作用机制与混合电位模型存在一些差异。乙硫氮（D^-）在脆硫锑铅矿表面不仅能化学吸附，而且能形成PbD2；溶液中过量的乙硫氮被催化氧化成双乙硫氮分子（D2），并物理吸附在矿物表面；当pH为6．86时，在实验的电位区间内，乙硫氮都使脆硫锑铅矿的界面电容降低，极化电阻增大，在-78—400mV电位区间，电阻明显增大；物理吸附的双乙硫氮分子D2和体相沉积的PbD2在矿物表面的附着能力差。

The spectrum and electrochemical adsorption behavior and mechanism of diethyl dithioearbamate on jamesonite were investigated by spectrum analysis and constantpotential step. Results indicated there was some difference between the mechanism and mixed potential model. On the surface of jamesonite, there are not only the chemisorption of diethyldithioeabamate （D-） but also PbD2 salt. The excessive D- in the solution is catalytically oxidized into dimer D2 which is physically adsorbed on the mineral. When pH is at 6.86, D- makes its interface capacitance decreased and makes its resistance increased in the range of wholly experimental potential, but the resistance increases obviously from - 78 mV to 400mV. Adhesive ability of both physical adsorption D2 and bulk-deposition PbD2 is weak on the surface of jamesonite.