體系中的電化學(xué)
( 1. 中南大學(xué)資源加工與生物工程學(xué)院， 長沙 410083;
2. 衡陽師范學(xué)院 化學(xué)與材料科學(xué)系，衡陽 421008)
摘 要: 采用循環(huán)伏安和交流阻抗法研究了脆硫銻鉛礦在乙硫氮-飽和Ca(OH)2體系中的電化學(xué)，討論了電位調(diào)控浮選脆硫銻鉛礦的工藝參數(shù)。電位在-378～22 mV范圍內(nèi)，礦物的界面電容不斷減少，介電常數(shù)變小，表面產(chǎn)物是疏水性的(CH3)2NCSS-、Pb((CH3)2NCSS-)2和S0；電位在22～222 mV范圍內(nèi)時，礦物表面的疏水產(chǎn)物膜迅速破裂，電容增加，介電常數(shù)變大，界面親水性增強(qiáng)。隨著電位的繼續(xù)升高，礦物表面不斷產(chǎn)生親水性離子和Fe(OH)3的沉積；對于乙硫氮-飽和Ca(OH)2水溶液體系，脆硫銻鉛礦的電位調(diào)節(jié)浮選的工藝參數(shù)應(yīng)控制在-178~122 mV之間，實(shí)際工藝中電位控制在-78mV~50 mV范圍為宜。
關(guān)鍵字: 浮選電化學(xué)； 脆硫銻鉛礦； 乙硫氮
HU Yue-hua1， QIN Wen-qing1
（ 1. School of Resource Processing and Bioengineering，Central South University， Changsha 410083，China;
2. Department of Chemistry and Material Science，
Hengyang Normal University， Hengyang 421008， China）
Abstract: Electrochemistry of jamesonite in the system of saturated Ca(OH)2 solution containing diethyl dithiocarbamate was investigated by voltammetry and electrochemical impedance methods. The processing parameters of potential-controlled flotation were discussed. The interface capacitance of jamesonite continuously decreased and its medium-charge constant became small when the electrode potential was from -378 mV to 22 mV. The compositions of products on jamesonite surface are hydrophobic (CH3)2NCSS-，Pb((CH3)2NCSS-)2 and S0. When the electrode potential was from 22 mV to 222 mV， its capacitance increases and its medium-charge constant becomes large due to the dissolution of the passive film. The hydrophilicity of jamesonite surface becomes strong. The hydrophilic ions and deposition of Fe(OH)3 formed with further enhancement of the electrode potential. The processing parameter must be controlled in the range from -178 mV to 122 mV and the potential range from -78 mV to 50 mV is controlled for potential-controlled flotation of jamesonite in the system of diethyl dithiocarbamate and saturated Ca(OH)2 solution.
Key words: flotation electrochemistry; jamesonite; diethyl dithiocarbamamte
