白云母矿石盐酸酸洗除钙试验研究  

Experimental study on calcium removal from muscovite ore by hydrochloric acid pickling

作　　者：夏孔海 马保中 杨慧 陈永强[1] 王成彦[1] XIA Konghai;MA Baozhong;YANG Hui;CHEN Yongqiang;WANG Chengyan(School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083

出　　处：《矿冶》2024年第2期303-309,共7页Mining And Metallurgy

基　　金：国家自然科学基金资助项目(52034002)。

摘　　要：随着我国双碳政策落实,能源等高新领域得到快速发展,对锂、铷等金属的需求日益增加,白云母作为含锂、铷矿物之一得以重视。针对在硫酸熟化处理白云母矿时,主要杂质钙的存在会降低有效提取率的问题,提出采用盐酸酸洗对白云母矿石进行预先除钙。首先,从热力学角度分析了酸洗时白云母和方解石与盐酸的反应情况,结果表明,在酸洗温度范围内,白云母几乎不与盐酸发生反应;当温度高于30℃时,方解石与盐酸反应可以自发进行。其次,通过对酸洗温度、盐酸浓度、酸洗时间和液固比等工艺参数的影响进行研究,结果表明:在酸洗温度70℃、盐酸浓度0.5 mol/L、酸洗时间1.5 h、液固比1 mL/g的条件下,钙的去除率可达98.3%,而铷和锂的损失率分别低至2.3%和3.3%。通过盐酸酸洗可实现白云母矿石中钙的选择性脱除。通过对酸洗渣进行表征发现,酸洗后白云母矿石中方解石相消失,矿石主要由白云母和石英组成,同时,电子能谱分析图像显示钙的富集区域消失。在相同的熟化和水浸条件下,对比直接熟化和酸洗+熟化两种不同工艺获得的锂和铷的浸出率发现,对酸洗后的白云母进行熟化可使锂、铷的提取率提高约10%~20%。最后,通过酸洗液循环除钙试验验证,酸洗液经补酸后(调节pH值至0.3)可供循环3次使用,钙的去除率均保持在90%以上,避免了废水的大量产生。With the implementation of double carbon policy in China,energy and other high-tech fields have been developed rapidly,the demand for lithium,rubidium and other metals is increasing,muscovite as one of the minerals containing lithium and rubidium has been paid attention to.In this paper,for the problem that the presence of the main impurity calcium will reduce the effective extraction rate when treating muscovite ore by sulfuric acid curing,it is proposed to use hydrochloric acid pickling to pre-calcium removal of muscovite ore.Firstly,the reaction of muscovite and calcite with hydrochloric acid during pickling was analyzed from the thermodynamic point of view.The results show that the muscovite hardly reacts with hydrochloric acid in the range of pickling temperature;when the temperature is higher than 30℃,the reaction between calcite and hydrochloric acid can be carried out spontaneously.Secondly,the process parameters such as pickling temperature,hydrochloric acid concentration,pickling time and liquid-solid ratio were investigated,and it has been found that the removal rate of calcium could reach 98.3%,while the loss rate of rubidium and lithium was as low as 2.3%and 3.3%under the conditions of pickling temperature of 70℃,hydrochloric acid concentration of 0.5 mol/L,pickling time of 1.5 h,and liquid-solid ratio of 1 mL/g.Therefore,the selective removal of calcium from muscovite ore can be achieved by hydrochloric acid pickling.Characterization of the pickling residue revealed that the calcite phase disappeared from the muscovite ore after pickling,and the ore was mainly composed of muscovite and quartz,while the EDS image showed the disappearance of calcium-enriched areas.Under the same curing and water leaching conditions,comparing the lithium and rubidium leaching rates obtained by two different processes,direct curing and pickling+curing,respectively,it was found that the curing of acid-washed muscovite could increase the lithium and rubidium extraction rate by about 10%to 20%.Finally,it was verified b

关 键 词：白云母 硫酸熟化 盐酸酸洗 选择性除钙 酸洗液循环 锂 铷 

分 类 号：TF826.3[冶金工程—有色金属冶金] TF826.4