某浮选微晶石墨精矿提纯试验研究

Study on the Refine of a Flotation Microcrystalline Graphite Concentrate

以某浮选微晶石墨精矿为对象,进行了原料矿物组成分析和采用超声—盐酸浸出、超声—硫酸和氢氟酸二次浸出工艺得到纯度为99.9%的产品试验研究。分析得出其杂质主要赋存在金属硅酸盐矿物中,部分杂质与微晶石墨紧密结合在一起,或被包裹。然后对原料用单因素变量法研究了超声加入、超声时间、盐酸加入量、反应温度、反应时间、硫酸和氢氟酸加入量对石墨中碳含量的影响,研究表明:在超声30 min,质量分数为37%盐酸加入量1 mL/g,搅拌浸出后抽滤、洗涤后,再次超声30 min,加入分析纯硫酸1.6 mL/g,质量分数为40%氢氟酸0.6 mL/g除杂,能获得高含量的石墨。

The mineral composition of the raw material was analyzed and the ultrasonic hydrochloric acid leaching,ultrasonic sulfuric acid and hydrofluoric acid(mixed acid)secondary leaching processes were used to obtain theproduct with purity of 99.9%.The analysis shows that the impurities mainly exist in the metal silicate minerals,and some impurities are closely combined with microcrysta-lline graphite or wrapped.Then,the effects of ultrasonic addition,ultrasonic time,hydrochloric acid dosage,reaction temperature,reaction time,sulfuric acid and hydrofluoric acid addition on carbon content in graphite were studied by single factor variable method.The results show that high content graphite can be obtained by ultrasonic wave for 30 min,adding 37%hydrochloric acid to 1 mL/g,stirring leaching,filtering and washing,and ultrasonic again for 30 min,adding 1.6 mL/g analytical pure sulfuric acid and 0.6 mL/g hydrofluoric acid with mass fraction of 40%.