(中南大學 冶金科學與工程學院，長沙 410083)
摘 要: 提出NaOH分解含銦鐵礬渣新工藝，考察NaOH用量、液固比、溫度和時間對鐵礬渣分解率的影響，并討論鐵礬渣中雜質金屬，如Zn、In、Cu、Cd、Pb、As、Sb、Sn和Ag等在NaOH分解過程中的行為。結果表明：在m(NaOH)׃m(鐵礬渣)=0.381 4׃1、溫度60 ℃、液固比2׃1、反應時間2 h的最優(yōu)條件下，鐵礬渣的分解率達到98.03%，而原料中的雜質金屬，如Sn、Sb、Zn、In、Cu、Cd、Pb和Ag等絕大部分留在分解渣中，As則以AsO43−的形態(tài)大部分進入溶液，浸出率達到83.36%。DSC-TGA熱分析和X射線衍射分析結果表明：在NaOH分解過程中，鐵礬渣中的鐵主要以Fe3O4形式沉淀入渣；分解渣中Fe、In和Zn的含量分別為38.81%、0.23%和12.89%；經稀鹽酸選擇性浸出銦和鋅后，進一步磁選富集可作為煉鐵原料。
關鍵字: 鐵礬渣；銦；濕法煉鋅；分解
（School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The decomposition of ammonium jarosite bearing indium in NaOH medium were studied. The effects of NaOH addition, liquid-solid ratio, decomposition temperature and time on the decomposition ratio of ammonium jarosite were investigated, respectively, and the behavior of impurity elements, such as Zn, In, Cu, Cd, Pb, As, Sb, Sn and Ag in jarosite residues was also discussed. The results show that the decomposition rate of ammonium jarosite can reach 98.03% under the following optimum conditions, which are m(NaOH)׃m(jarosite)=0.381 4׃1, temperature 60 ℃, liquid-solid ratio 2׃1, reaction time 2 h. During the alkaline decomposition, the impurity elements, such as Zn, In, Cu, Cd, Pb, Sb, Sn and Ag are left in the residue, while As is leached into the pregnant solution as AsO43− with leaching rate of 83.36%. DSC-TGA thermal analysis and XRD characterization results demonstrate that Fe is precipitated as Fe3O4 during alkaline decomposition of jarosite. The contents of Fe, In and Zn in decomposition residue are 38.81%, 0.23% and 12.89%, respectively. After selective leaching of In and Zn with dilute HCl solution, the iron concentrates obtained from magnetic separation can be used as raw material for iron smelting.
Key words: ammonium jarosite; In; zinc hydrometallurgy; decomposition
