(1. 中南大學(xué) 冶金與環(huán)境學(xué)院，長沙 410083；
2. 中南大學(xué) 國家重金屬污染防治工程技術(shù)研究中心，長沙 410083；
3. 中南大學(xué) 湖南省戰(zhàn)略金屬礦產(chǎn)資源清潔高效利用協(xié)同創(chuàng)新中心，長沙 410083)
摘 要: 采用浸出方法使砷濾餅中的銅砷元素進(jìn)行分離，銅以硫化銅的形式沉淀，砷以砷酸根離子進(jìn)入溶液中。考察NaCl濃度、Na2S添加量、液固比、時(shí)間及溫度等因素對砷濾餅中砷、銅浸出率的影響。得出最優(yōu)的工藝條件如下：NaCl溶液濃度為20g/L、液固比7:1、Na2S與砷濾餅質(zhì)量比3:4、浸出時(shí)間4 h、溫度80 ℃、H2O2 20 mL。在此最優(yōu)工藝條件下，砷浸出率高達(dá)95.56%，銅浸出率低于0.5%，浸出渣銅含量富集至33.6%。浸出液采用硫酸亞鐵沉砷方法，沉砷率可以達(dá)到98%，生成的砷酸鐵晶體含砷量為32.15%，濾液含砷量為0.23g/L，濾液可以返回浸出過程，實(shí)現(xiàn)循環(huán)利用。
關(guān)鍵字: 砷濾餅；銅；砷；分離；浸出；脫砷
（1. School of Metallurgy and Environment, Central South University, Changsha 410083, China;
2. Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution, Central South University, Changsha 410083, China;
3. Co-Innovation Center for Clean and Efficient Utilization of Strategic Metal Mineral Resources, Central South University, Changsha 410083, China）
Abstract:Leaching method was used to separate copper and arsenic in the arsenic filtration cake, which was achieved by the formation of CuS in the residue and AsO43- in the solution during the leaching process. The effects of various parameters, such as concentrations of NaCl, mass ratio of Na2S to arsenic filtration cake, liquid-solid ratio, leaching time and temperature, on leaching rate of As and Cu were investigated. On this basis, the optimal conditions are obtained through single factor experiment as follows, 20 g/L NaCl, liquid-solid ratio 7:1, mass ratio of Na2S to arsenic filtration cake 3:4, leaching at 80 ℃ for 4h, with 20 mL H2O2. Under this optimal condition, the leaching rate of As reaches 95.56%, and leaching rate of Cu is less than 0.5%. The copper content in leaching residue is as high as 33.6% (mass fraction). In addition, arsenic-containing leachate can be treated with FeSO4 and removal rate of As in leachate exceeds 98%. Arsenic content in the generated crystal is 32.15% (mass fraction), and arsenic concentration in the effluent is 0.23 g/L which can be returned to the leaching process.
Key words: arsenic filtration cake; copper; arsenic; separation; leaching; arsenic removal
