铜电解液中砷氧化还原规律及价态转化途径  

Redox Rule of Arsenic in Copper Electrolyte and Its Valence Transformation Method

作　　者：毛建伟[1] 肖发新[1] 曹岛[1] 刘昆鹏[1] 

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471023

出　　处：《河南科技大学学报（自然科学版）》2013年第5期9-14,4-5,共6页Journal of Henan University of Science And Technology:Natural Science

基　　金：国家自然科学基金项目(50904023);河南省教育厅自然科学研究基金项目(2010B450001)

摘　　要：以含H2SO4、As、Sb、Bi的酸性溶液为研究体系,采用化学分析及电化学测试研究了电解液中砷的氧化还原规律及价态转化途径。试验结果表明:溶解在铜电解液中的空气在一定温度下将As3+氧化,而且Sb可显著促进As3+的氧化。通过向电解液中通入适量的SO2可实现电解液中砷的价态调控,促进砷锑铋的共沉淀反应。采用SO2还原电解液中的As5+,使砷物质的量比(n(As3+)/n(As5+))维持在1∶1附近,Sb、Bi在一定条件下脱除率分别高达60.0%和46.0%。电化学测试表明:加入As3+后,阴极过程在-0.1～-0.2 V出现还原峰,随着As3+加入量增大,峰电位负移。加入As5+后,阳极和阴极过程分别在-0.01 V和-0.18 V附近出现氧化峰和还原峰,随着As5+浓度的增加,氧化峰电流逐渐增大;还原峰电位负移,峰电流先增大后减小。The redox rule of arsenic in copper electrolyte and its valence transformation method were studied by means of chemical analysis and electrochemical test in the acid solution containing H 2 SO 4 ,As,Sb and Bi. The results show that the air (O 2) dissolved in copper electrolytes can effectively oxidize arsenic,and Sb can accelerate the oxidation of arsenic. The valence of As 5 + can be transformed to As 3 + by adding a proper amount of SO 2 into the electrolyte,which accelerates the co-precipitation reactions among arsenic,antimony and bismuth. The removal rates of Sb and Bi reach 60. 0% and 46. 0% ,respectively under a certain condition after the arsenic mol ratio of As 3 +/As 5 + is adjusted to 1∶ 1 approximately by SO 2 . Electrochemical test results show the As 3 + cathode process appears a new reduction peak at the potential of - 0. 1 V to - 0. 2 V,and the peak potential shifts negatively with the increase of As 3 + ion concentration. The oxidation and reduction peaks appear near the potential of - 0. 01 V and - 0. 18 V,respectively in the anodic and cathode process of As 5 + ion. With the increase of As 5 + ion concentration,the oxidation peak current gradually increases. The reduction peak potential shifts towards negative direction and the peak current increases first and then decreases.

关 键 词：铜电解液 砷 氧化还原 价态转化 

分 类 号：TF811[冶金工程—有色金属冶金]