Selective leaching of arsenic from copper converter flue dust by Na2S and its stabilization with Fe2(SO4)3  

Na2S选择性浸出铜转炉烟灰中的砷及Fe2(SO4)3稳定化砷

作　　者：Amirhossein SHAHNAZI Sadegh FIROOZI Davoud HAGHSHENAS FATMEHSARI Amirhossein SHAHNAZI;Sadegh FIROOZI;Davoud HAGHSHENAS FATMEHSARI(Department of Mining and Metallurgical Engineering,Amirkabir University of Technology,424 Hafez Ave.,Tehran 15875-4413,Iran)

机构地区：[1]Department of Mining and Metallurgical Engineering,Amirkabir University of Technology,424 Hafez Ave.,Tehran 15875-4413,Iran

出　　处：《Transactions of Nonferrous Metals Society of China》2020年第6期1674-1686,共13页中国有色金属学报（英文版）

摘　　要：The alkaline leaching of arsenic (As2O3) by Na2S, together with its precipitation by Fe2(SO4)3 was studied. Response surface methodology based on central composite design was employed to quantify and qualify the effect of pertinent factors and to develop statistical models for optimization purposes. Based on the obtained results, 89% of arsenic is removed from the dust under following optimum predicted conditions: Na2S concentration of 100 g/L and solid to liquid ratio of 0.163 g/mL at 80 °C. It is found that solid to liquid ratio and Na2S concentration are the significant factors influencing the leaching process. In the precipitation process, more than 99.93% of arsenic from the leaching solution is removed in the form of amorphous ferric arsenate, at pH 4.8 when Fe3+ to arsenic and H2O2 to arsenic molar ratios are set at 5:1 and 4:1, respectively. Also, Fe3+ to arsenic ratio and pH are the most significant factors, and the interaction between these terms is significant.研究砷(As2O3)的Na2S碱性浸出,以及用Fe2(SO4)3沉淀砷。采用基于中心组合设计的响应面法对相关因素的影响进行定量和定性分析,提出用于参数优化的统计模型。结果表明,在Na2S浓度100 g/L,固液比0.163 g/mL和温度80℃的最优预测条件下,89%的砷可从烟灰中去除。研究发现,固液比和Na2S浓度是影响浸出过程的显著因素。在沉淀过程中,当pH为4.8、Fe3+与砷的摩尔比和H2O2与砷的摩尔比分别为5:1和4:1时,浸出液中99.93%以上的砷以无定形砷酸铁的形式被除去。Fe3+与砷的摩尔比和pH值为最显著因素,而且他们之间的相互作用也是显著的。

关 键 词：flue dust ARSENIC response surface methodology alkaline leaching PRECIPITATION 

分 类 号：TF811[冶金工程—有色金属冶金]