(中南工業(yè)大學(xué)冶金物理化學(xué)研究所， 長沙410083)
摘 要: 以高溫合成法制備了FeS，用電位掃描、 旋轉(zhuǎn)電極、恒電位電解等技術(shù)研究了FeS在電解液0.5 mol/L H2SO4+0.5mol/L K2SO4 (25℃， pH=0.70)中的陽極氧化過程。結(jié)果表明， FeS陽極氧化過程遵循“活性氧化—鈍化—活性氧化”規(guī)律，在0.7～1.4 V (vs SCE)之間出現(xiàn)鈍化區(qū)。第一個活性氧化區(qū)的Tafel方程為η=0.468+0.0289 lnJ， 在高過電位區(qū)， FeS陽極反應(yīng)受固相擴(kuò)散傳質(zhì)步驟控制，有少量高價態(tài)的S化合物生成。
關(guān)鍵字: FeS； 磁黃鐵礦； 陽極氧化
（Institute of Metallurgical Physiochemistry,
Central South University of Technology, Changsha 410083，P.R.China）
Abstract:FeS was synthesized with Fe and S at high temperature. The electrochemical techniques, such as potential sweep, rotated disc electrode, and coulometry, were employed to probe the anodic oxidization behavior of FeS in the solution of 0.5 mol/L H2SO4+0.5 mol/L K2SO4 (0.25℃, pH=0.70). Experimental results demonstrated that the anodic oxidization behavior obeys the mode of activation oxidization—passivation—activation oxidization. Passivation occurs in the range of 0.7～1.4 V (vs SCE). The Tafel equation for the first activation oxidization zone isη=0.468+0.0289lnJ. Under the condition of higher overpotential, the anodic reactions are controlled by the step of the Fe solid diffusion. The products in anodic process are Fe3+ and S, and a small amount of sulfur compound with high valence is produced under higher overpotential.
Key words: FeS; pyrrhotite; anodic oxidization
