A study on recovery of indium from electrolytic indium anode slime

• Main Authors: Yi-Yun Chen, 陳怡雲
• Other Authors: 柯明賢
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/978bzc

碩士 === 國立臺北科技大學 === 資源工程研究所 === 100 === The electrolytic indium anode slime is produced from the electrolytic purification process of crude indium. The electrolytic anode slime still contains obvious quantity of indium that is worthy of recovering, but it contains some impurities that is worthy of recovering, but it contains some impurities that the contents and the concentrations depend on its source. In this study, the properties of two electrolytic indium anode slimes from the different source were investigated. The recovery feasibility and efficiency of indium in two electrolytic indium anode slimes were evaluated. The results from the analysis of properties indicate that the shape of electrolytic indium anode slime containing higher quantity of tin, iron and copper is flaky（#1）and the shape of electrolytic indium anode slime containing lower quantity of tin, iron and copper is muddy（#2）. The leaching efficiency of indium in the electrolytic indium anode slime by sulfuric acid and hydrochloric acid was studied. The results of acid leaching show that the optimum operating conditions are: sulfuric acid 150 g / L + hydrochloric acid 100 g / L, liquid to solid ratio 7.1, reaction time 1hr（#1）/2hr（#2） and reaction temperature 80 ° C（#1）/60 ° C（#2）, and the leaching efficiency of indium in two different sources of electrolytic indium anode slimes reaches more than 90%. The sequential and jarosite removing impurity processes were used to remove impurity such as tin, copper and iron etc. in the leach solution. The optimum pH for removing copper and iron is respectively 1.1 and 1.7 by the sequential removing impurity process, and the removal efficiency of iron and tin respectively reaches to 93.24% (#1)/75.35% (#2) and 100%, however the loss of indium also reaches to 24.65% (#1)/11.50% (#2). The optimum operating conditions for jarosite removing impurity process are: reaction time 3hr, pH 1.7 (#1)/1.5 (#2) and (NH4) 2SO4 / (NH4) 2Fe6 (SO4) 4 (OH) 12 addition ratio 1/12, and he removal efficiency of iron and tin both reaches to 90%, but the loss of indium reaches to 40.72%. Then the zinc powder was used to replace indium to produce crude indium in the leaching solution after removing impurity process. The crude indium is called sponge indium and the efficiency of removing impurity could affect the shape of sponge indium. The higher efficiency of removing impurity is, and the smoother shape of crude indium is. Based on the above results of this study, it shows that the hydrometallurgical process could be used for recovering indium from the electrolytic indium anode slime.