Preparation of High-grade Germanium Concentrate by Acid Pickling of Tannic Germanium Residue
In view of the problems of low impurity removal rate and low grade of germanium concentrate in the washing process of tannin germanium residue,the As,Zn and Fe impurities in tannin germanium residue were effectively removed by washing with dilute sulfuric acid solution.The effects of sulfuric acid mass concentration,washing temperature and washing time,liquid volume to solid mass ratio on the removal rate of As,Zn and Fe impurities and Ge loss rate were investigated.The results show that under the conditions of sulfuric acid mass concentration of 60 g/L,liquid volume to solid mass ratio of 5 mL/1 g,washing temperature of 60 ℃,first washing time of 120 min,second washing and third washing time of 60 min,the cumulative removal rates of As,Zn and Fe can reach over 88％,97％and 95％,respectively.Ge cumulative loss rate is less than 1.50％.The Ge and As grades of germanium concentrate prepared by three-stage countercurrent pickling and oxidation roasting process are 34.45％and 0.54％,respectively,which meet the tertiary standard of germanium concentrate.
国家科技期刊平台
NSTL
万方数据
