(中南大學(xué) 冶金科學(xué)與工程系, 長沙 410083)
摘 要: 繪制了Cu-As-H2O系電位--pH圖、不同As濃度下lg(［Cu］T/［As］T)--pH圖以及Fe-As(Ⅴ)-H2O系lg［Fe］T--pH圖等，分析了由黑銅渣制備砷酸銅過程的熱力學(xué)。酸性氧化浸出可同時浸出Cu和As，pH=2左右脫鐵率可達99%以上。銅砷比和pH值的不同，可以得到不同形式的砷酸銅：CuHAsO4,Cu2AsO4OH，Cu5H2(AsO4)4。在砷酸銅制備工藝條件下，所得砷酸銅分子式為Cu5H2(AsO4)4。熱力學(xué)分析結(jié)果與XRD相一致。
關(guān)鍵字: 熱力學(xué); 砷酸銅; 浸出; 脫雜
arsenate preparation process
（Department of Metallurgy Science and Engineering,
Central South University, Changsha 410083, P.R.China）
Abstract:The thermodynamics of copper arsenate preparation from black copper sludge was analyzed by constructing potential--pH diagram of Cu-As-H2O system， lg［Cu］T/［As］T--pH diagram at different concentration of arsenic，lg［Fe］T--pH diagram of Fe-As(Ⅴ)-H2O system. In acid oxidative leaching of the black copper sludge Cu and As can be leached simultaneously; in neutralization process of the mother liquor after copper sulfate crystallization Fe can be precipitated and its separation efficiency reaches more than 99% at pH=2. With the difference of［Cu］T/［As］T ratio and pH, the different shape copper arsenate: CuHAsO4，Cu2AsO4OH and Cu5H2(AsO4)4 can be formed. Under the technological conditions of copper arsenate preparation the molecular formula of copper arsenate prepared is Cu5H2(AsO4)4.The result of thermodynamic analysis is consistent with XRD.
Key words: thermodynamic; copper arsenate; leaching; impurity separation
