钠离子交换法从黑云母中提钾及水钠云母的电化学性能

为了解决我国钾资源短缺的问题，从难溶性钾矿物中提取可溶性钾元素的技术需要被进一步研究。以钾含量相对较高的黑云母为研究对象，通过钠离子交换法从黑云母中提取出可溶性钾元素并制备出水钠云母负极材料。在80 ℃的水热反应温度下，钾离子与钠离子发生交换，通过过滤反应液从滤液中获取可溶性钾盐并得到水钠云母负极材料。X-射线衍射结果表明:反应后的云母层状硅酸盐结构未被破坏，8 h内提钾率高达92.3%。通过电化学工作站测定黑云母及提钾后水钠云母的电化学性能，在0.4 A/g电流密度下进行恒流充放电，测得水钠云母负极材料的首次放电比电容为9.8 F/g，较黑云母原矿的电化学性能有明显的提高。

Potassium Extraction from Biotite by Sodium Ion Exchange and Electrochemical Properties of Hydrated Sodium Mica

To solve the problem of shortage of potassium resources in China，the technology of extracting soluble potassium from insoluble potassium minerals needs to be further studied. The soluble potassium was extracted from biotite by sodium ion exchange method and the aqueous sodium mica anode material was prepared. At the temperature of 80 ℃，potassium ion was exchanged with sodium ion，and the soluble potassium salt was obtained from the filtrate by filtering the reaction liquid，and the hydrated sodium mica negative electrode material was obtained. X-ray diffraction results show that the structure of mica phyllosilicates is not destroyed and the potassium extraction rate is as high as 92.3% within 8 h. The electrochemical performance of biotite and aqueous sodium mica after potassium extraction were determined by electrochemical workstation. Constant current charge and discharge was carried out at the current density of 0.4 A/g，and the first discharge specific capacity of hydrated sodium mica negative electrode material was measured to be 9.8 F/g，indicating it has better electrochemical performance than biotite mineral.