Recovery of tellurium from sodium carbonate slag
This study is devoted to tellurium recovery from sodium carbonate slag, formed in the fire refining process of crude silver. The slag was modified by silica additions and then reduced by carbon oxide. The degree of the slag modification was defined by the parameter kw: kw=nSiO2/nNa2CO3+nNa2O where:.inthe mole numbers of silica, sodium carbonate and sodium oxide. The compositions of the investigated slag determined by the parameter kw and the mole fraction of the tellurium oxide (xTeO2) are given in the following table. The reduction of tellurium was very fast for all the investigated slags, which was manifested by an almost complete conversion of CO into CO2. Unfortunately, at the same time, a side reaction took place, and as a results sodium telluride was formed, which reported to the slag:(Na2O)slag+Te(g)+CO=(Na2Te)slag+CO2 The tellurium content in the reduced slag decreases as the parameter SD increases, and only the slag with the SD equal unity was suitable for the tellurium recovery in form of dusts, containing more than 76 wt-％ tellurium.
tellurium recovery crude silver refining sodium carbonate slag
M. Kucharski P. Madej M. W(e)drychowicz T. Sak W. Mróz
AGH University of Science and Technology, Department of Metallurgy of Non-Ferrous Metals, 30 Mickiewicza Avenue, 30-019 Kraków, Poland
国际会议
Ninth International Conference on Molten Slags,Fluxes and Salts(第九届国际熔渣、溶剂与熔盐学术会议 MOLTEN12)
北京
英文
1-13
2012-05-27（万方平台首次上网日期，不代表论文的发表时间）