钾长石混盐焙烧-浸出提钾过程研究

Study on extraction of potassium from K-feldspar by roasting⁃leaching of mixed salts

中国钾盐资源匮乏,而钾长石是一种重要的钾赋存形式。然而,钾长石的开发技术难度大、成本高,至今尚未实现工业化应用。为了解决钾长石开发利用过程中钾提取温度高、浸出率低等问题,该研究选取了贵州铜仁地区钾长石矿为研究对象,探究了钾长石-硫酸钠-碳酸钙混盐的焙烧-浸出过程,考察了钾长石-硫酸钠-碳酸钙的焙烧配比、焙烧温度、焙烧时间、浸取剂浓度等因素对钾长石中钾元素浸出率的影响。实验结果显示,在焙烧体系均匀混合、焙烧温度为800~900℃、焙烧时间为1 h、m(钾长石)∶m(硫酸钠)∶m(碳酸钙)为(1∶1∶6)^(1∶1∶8)条件下,以质量分数为5%NaOH溶液作为浸取液,钾的浸出率可高达99.79%。该研究提供了一条提高钾长石资源利用效率、解决钾盐资源供应问题的新途径,并为相关工业生产提供了有力的技术支持。

Potash resources are scarce in China,and K-feldspar is an important form of potassium occurrence.However,the development of K-feldspar involves significant technical challenges and high costs,and industrial utilization has not yet been achieved.To address issues like high temperatures and low leaching rates during the development and utilization of K-feldspar,the K-feldspar ore from the Guizhou Tongren was selected as research target in this study,and the mixed-salt roasting-leaching process of K-feldspar-sodium sulfate-calcium carbonate was investigated.The effects of factors such as the ratios of K-feldspar-sodium sulfate-calcium carbonate roasting,roasting temperature,roasting time,and leaching reagent on the leaching rate of potassium elements in K-feldspar were explored.The experimental results indicated that under condi-tions of uniform roasting mixture,roasting temperatures within the range of 800∼900℃,roasting time of 1 h,a roasting com-position ratio of ore,sodium sulfate,and calcium carbonate at(1∶1∶6)~(1∶1∶8),and leaching using a mass fraction of 5%NaOH solution,the leaching rate of potassium could reach as high as 99.79%.This study offered a new approach to enhance the efficiency of K-feldspar resource utilization and address potassium resource supply issues.Moreover,it provided robust technical support for relevant industrial production.