承德某高硅铁尾矿碱浸硅工艺条件研究

Research on the Process Conditions of Leaching Silicon with Alkali from Chengde High-silicon Iron Tailings

承德某高硅铁尾矿Si O2含量为65.27%,主要含硅矿物为石英和高岭石。为高附加值地开发利用该铁尾矿,从回收硅的角度进行了研究。结果表明,以Na OH为浸硅剂,硅的转化率随着浸出温度、浸出时间和液固比的增大而增大,随着Na OH初始浓度的增大先增大后减小;各因素对硅转化率影响的主次顺序为浸出温度>浸出时间>Na OH初始浓度>液固比;在浸出温度为140℃,浸出时间为5 h,Na OH初始浓度为55%,液固比为5.5∶1情况下,硅的转化率达96.14%,为承德高硅铁尾矿的利用提供了技术支持。

The content of Si O2 in a high-silicon iron tailing in Chengde is 65.27%,and the main silicon-containing minerals are quartz and kaolinite. In order to develop and utilize the iron tailings for high additional value,study was conducted from the point of view of recovering silicon. The results show that when Na OH is used as silicon leaching agent,the conversion rate of silicon increases with the increase of leaching temperature,leaching time and liquid-solid ratio,while increases first and then decreases with the increase of initial Na OH concentration. The primary and secondary order of the factors affecting the conversion rate of silicon are the leaching temperature leaching time initial concentration of Na OH liquid-solid ratio. When leaching temperature is 140 ℃,leaching time is 5 h,initial concentration of Na OH is 55% and the ratio of liquid to solid is 5.5∶1,the conversion rate of silicon reaches 96.14%,which provides technical support for the utilization of Chengde high-silicon iron tailings.