(中南工業(yè)大學資源環(huán)境與建筑工程學院，長沙 410083)
摘 要: 據(jù)熱力學參數(shù)，計算得到砷酸、亞砷酸、單質(zhì)砷析出砷化氫的標準平衡電勢值分別為0.144 V， 0.005V，-0.238 V。在銅電解液凈化工序中，砷酸優(yōu)先于亞砷酸析出砷化氫，當陰極電勢足夠負時，三者共同放電析出砷化氫。計算結(jié)果與實測結(jié)果基本吻合，均表明砷化氫析出的標準平衡電勢值正于-0.608 V。在銅凈液工序中，采用控制陰極電勢脫銅脫砷電積法，能有效抑制砷化氫的析出。
關鍵字: 砷化氫；析出電勢；銅電解液
（College of Resource, Environment and Civil Engineering,
Central South University of Technology, Changsha 410083, P.R.China）
Abstract:The standard equilibrium potentials of evolving AsH3 from arsenic acid, arsenious acid and element arsenic are thermodynamically calculated as 0.144V, 0.005V, -0.238 V respectively. In the processing of the purification of copper electrolyte, arsenic acid prior to arsenious acid evolves AsH3. When cathodic potential is negative enough, arsenic acid, arsenious acid and element arsenic co-discharge and AsH3 is evolved. The results of thermodynamical calculation are basically concordance with the measured results. The standard equilibrium potential of AsH3 evolution is absolutely more positive than -0.608V. In the processing of the purification of copper electrolyte, the separation of copper and arsenic by electrowinning of controlling cathodic potential can prevent AsH3 from evolving effectively.
Key words: arsine; evolution potential; copper electrolyte
