This hydrometallurgical method consists of oxidation leaching, sulfide impurities removing, and sulfur dioxide reduction. The crude tellurium powder was treated by H2Oa oxidation for 2.0 h at pH 2.5 when adding 50 ml ...This hydrometallurgical method consists of oxidation leaching, sulfide impurities removing, and sulfur dioxide reduction. The crude tellurium powder was treated by H2Oa oxidation for 2.0 h at pH 2.5 when adding 50 ml H2O2 （30 %） per 100 g raw material, a tellurium recover rate around 91% is achieved. The tellurium leaching ratio can reach 98.9 % under 3.75 mol.L-1 NaOH concentration in liquid-solid ratio of 5：1 at 80 ℃ for 1.5 h. The overall separation of tellurium and other heavy metals is optimum at sulfide dosages of about 1.1 times of the theoretical values. The removal rates of Ag, Ni, Pb, and Cu from the solution are greater than 99.8 %, and As and Se removal rates are 98.6 % and 97.2 %, respectively. Over 99.5 % tellurium can be recovered by SOu reaction when the operation is conducted at 85 ℃ in 6 mol.L-1 HC1 solution. The tellurium powder with size of 〈5 μm and purity of 〉99.999 % is obtained.展开更多
基金financially supported by the Science and Technology Department of Guangdong Province(No.2011B0508000033)
文摘This hydrometallurgical method consists of oxidation leaching, sulfide impurities removing, and sulfur dioxide reduction. The crude tellurium powder was treated by H2Oa oxidation for 2.0 h at pH 2.5 when adding 50 ml H2O2 （30 %） per 100 g raw material, a tellurium recover rate around 91% is achieved. The tellurium leaching ratio can reach 98.9 % under 3.75 mol.L-1 NaOH concentration in liquid-solid ratio of 5：1 at 80 ℃ for 1.5 h. The overall separation of tellurium and other heavy metals is optimum at sulfide dosages of about 1.1 times of the theoretical values. The removal rates of Ag, Ni, Pb, and Cu from the solution are greater than 99.8 %, and As and Se removal rates are 98.6 % and 97.2 %, respectively. Over 99.5 % tellurium can be recovered by SOu reaction when the operation is conducted at 85 ℃ in 6 mol.L-1 HC1 solution. The tellurium powder with size of 〈5 μm and purity of 〉99.999 % is obtained.
