Arsenic is selectively extracted from high-arsenic dust by NaOH-Na2S alkaline leaching process. In the leaching arsenic process, the effects of alkali-to-dust ratio, sodium sulfide addition, leaching temperature, leac...Arsenic is selectively extracted from high-arsenic dust by NaOH-Na2S alkaline leaching process. In the leaching arsenic process, the effects of alkali-to-dust ratio, sodium sulfide addition, leaching temperature, leaching time and liquid-to-solid ratio on metals leaching efficiencies were investigated. The results show that the arsenic can be effectively separated from other metals under the optimum conditions of alkali/dust mass ratio of 0.5, sodium sulfide addition of 0.25 g/g, leaching temperature of 90 ℃, leaching time of 2 h, and liquid-to-solid ratio of 5：1 （mL/g）. Under these conditions, the average leaching efficiencies of arsenic, antimony, lead, tin and zinc are 92.75%, 11.68%, 0.31%, 29.75% and 36.85%, respectively. The NaOH-Na2S alkaline leaching process provides a simple and highly efficient way to remove arsenic from high-arsenic dust, leaving residue as a suitable lead resource.展开更多
Copper dust with high arsenic content is a hazardous waste that should be treated properly.Herein,the copper dust is oxidized,leached,and separated at room temperature and atmospheric pressure.To separate As and Bi,pa...Copper dust with high arsenic content is a hazardous waste that should be treated properly.Herein,the copper dust is oxidized,leached,and separated at room temperature and atmospheric pressure.To separate As and Bi,part of As(Ⅲ)in copper dust is oxidized to As(V),so that most of the As,Cu,and Zn elements enter the solution and the Bi remains in the leaching residue.Also,the influence of several factors,such as H_(2)SO_(4) dosage,H_(2)O_(2) dosage,liquid-solid ratio,leaching temperature and leaching time,on the leaching percentage of As,Bi,Cu,and Zn is systematically investigated.The optimal conditions are obtained as follows:liquid-solid ratio of 3:1,H_(2)O_(2) dosage of 10 ml/50 g(dust),H_(2)SO_(4) dosage of 4.5 ml/50 g(dust),leaching temperature of 85 C,and leaching time of 3 h.Under these conditions,the leaching percentage of As,Cu,Zn,and Bi is found to be 97.39%,96.11%,97.32%,and 2.40%,respectively.For further recovery of As from the leaching solution,the one-step recycle leaching of the leaching solution is performed to increase the concentration of As in the recycled leaching solution.The concentration of arsenic in the recycling leaching solution is found to be 79.63 g·L^(-1),which is beneficial for the study on further recovery of As_(2)O_(3).展开更多
本研究先以水浸实现砷碱渣中的砷锑分离,再对水浸渣进行盐酸浸出,得到了可作为工业原料氯化锑溶液。研究结果表明,在液固比为6∶1,温度40℃,浸出时间40 m in的条件下,可使水浸过程中锑的浸出率低于3%,砷的浸出率达到99%;盐酸浸出中,控...本研究先以水浸实现砷碱渣中的砷锑分离,再对水浸渣进行盐酸浸出,得到了可作为工业原料氯化锑溶液。研究结果表明,在液固比为6∶1,温度40℃,浸出时间40 m in的条件下,可使水浸过程中锑的浸出率低于3%,砷的浸出率达到99%;盐酸浸出中,控制酸浓度为1∶1,液固比10∶1,温度60℃,浸出时间30 m in,能使锑的浸出率达到88%以上。经过水浸和盐酸浸出,锑的直接回收率为85.36%。展开更多
基金Project(2012AA04022)supported by the Scientific Research and Technology Development Project of Guangxi,China
文摘Arsenic is selectively extracted from high-arsenic dust by NaOH-Na2S alkaline leaching process. In the leaching arsenic process, the effects of alkali-to-dust ratio, sodium sulfide addition, leaching temperature, leaching time and liquid-to-solid ratio on metals leaching efficiencies were investigated. The results show that the arsenic can be effectively separated from other metals under the optimum conditions of alkali/dust mass ratio of 0.5, sodium sulfide addition of 0.25 g/g, leaching temperature of 90 ℃, leaching time of 2 h, and liquid-to-solid ratio of 5：1 （mL/g）. Under these conditions, the average leaching efficiencies of arsenic, antimony, lead, tin and zinc are 92.75%, 11.68%, 0.31%, 29.75% and 36.85%, respectively. The NaOH-Na2S alkaline leaching process provides a simple and highly efficient way to remove arsenic from high-arsenic dust, leaving residue as a suitable lead resource.
基金This work was financially supported by the Fundamental Research Funds for the Central South University. Postdoctoral Research Foundation of Central South University (140050037).
文摘Copper dust with high arsenic content is a hazardous waste that should be treated properly.Herein,the copper dust is oxidized,leached,and separated at room temperature and atmospheric pressure.To separate As and Bi,part of As(Ⅲ)in copper dust is oxidized to As(V),so that most of the As,Cu,and Zn elements enter the solution and the Bi remains in the leaching residue.Also,the influence of several factors,such as H_(2)SO_(4) dosage,H_(2)O_(2) dosage,liquid-solid ratio,leaching temperature and leaching time,on the leaching percentage of As,Bi,Cu,and Zn is systematically investigated.The optimal conditions are obtained as follows:liquid-solid ratio of 3:1,H_(2)O_(2) dosage of 10 ml/50 g(dust),H_(2)SO_(4) dosage of 4.5 ml/50 g(dust),leaching temperature of 85 C,and leaching time of 3 h.Under these conditions,the leaching percentage of As,Cu,Zn,and Bi is found to be 97.39%,96.11%,97.32%,and 2.40%,respectively.For further recovery of As from the leaching solution,the one-step recycle leaching of the leaching solution is performed to increase the concentration of As in the recycled leaching solution.The concentration of arsenic in the recycling leaching solution is found to be 79.63 g·L^(-1),which is beneficial for the study on further recovery of As_(2)O_(3).
文摘本研究先以水浸实现砷碱渣中的砷锑分离,再对水浸渣进行盐酸浸出,得到了可作为工业原料氯化锑溶液。研究结果表明,在液固比为6∶1,温度40℃,浸出时间40 m in的条件下,可使水浸过程中锑的浸出率低于3%,砷的浸出率达到99%;盐酸浸出中,控制酸浓度为1∶1,液固比10∶1,温度60℃,浸出时间30 m in,能使锑的浸出率达到88%以上。经过水浸和盐酸浸出,锑的直接回收率为85.36%。
