粉煤灰中锗的高温火法二次富集工艺

Germanium enrichment from ash by second enrichment process at high temperature

采用高温火法二次富集工艺对含锗粉煤灰中的锗进行富集,以锗含量为0.35%(质量分数)的粉煤灰为原料,研究温度、C含量、碱度、保温时间等工艺参数,对高温火法二次富集工艺锗的富集的影响。结果表明:当粉煤灰中碳含量为3%,碱度为1.0,在1600℃下保温1 h可以取得较好的锗富集效果。富集物中锗含量可达到16.65%,富集物中锗的收得率达到89.55%。对富集后的富集物和渣进行XRD物相分析,富集后锗以锗酸盐(Ca_2Ge O_4和Ca_2Ge_7O_(16))和FeGe形式在富集物中存在,渣呈玻璃相,有利于锗的提取。

The enrichment of germanium from the ash was adopted by new method of second enrichment technology at high temperature in this experiment. The ash with 0.35% germanium was used as raw material. Effects of the parameters, such as temperature, C content, basicity and soaking time, on second enrichment of germanium were investigated. The results show that the effect of germanium enrichment is better when the carbon content is 3% in the ash, the basicity is 1, and it is insulated for 1 h at 1600 ~C. The germanium content in the enrichment is 16.65%, and the yield rate of the germanium is 89.55%. The enrichment and slag were analyzed by X-ray diffraction （XRD）, the results show that the germanium in the enrichment exists as germanates and FeGe, and the slags exists as glass phase, which is propitious to the extraction of germanium.