硫酸法从锂磷铝石中提取锂工艺研究及优化  

Study and optimization of lithium extraction from amblygonite by the sulfuric acid method

作　　者：邓红云 钟盛文[1] 刘雨鑫 彭卫发 张绍军[2] DENG Hongyun;ZHONG Shengwen;LIU Yuxin;PENG Weifa;ZHANG Shaojun(Faculty of Materials Metallurgy and Chemistry,Jiangxi University of Science and Technology,Ganzhou 341000,Jiangxi,China;Yichun Vocational Technical College,Yichun 336000,Jiangxi,China)

机构地区：[1]江西理工大学材料冶金化学学部,江西赣州341000 [2]宜春职业技术学院,江西宜春336000

出　　处：《有色金属科学与工程》2022年第4期35-43,共9页Nonferrous Metals Science and Engineering

摘　　要：研究了硫酸法从锂磷铝石中提取锂的工艺。研究结果表明,当矿物与硫酸质量比为1∶0.4、焙烧温度为780~820℃、浸出液固质量比为1.6∶1时,锂提取率达96%以上;将硫酸锂溶液用NaOH调节pH值为12,可彻底去除溶液中的Al^(3+)、Fe^(3+)、PO_(4)^(3-)杂质,所得硫酸锂溶液用EDTA络合Ca^(2+)后,与Na_(2)CO_(3)溶液反应可获得电池级碳酸锂。针对混酸料呈稀糊状和物料中的氟元素难处理两大问题展开工艺优化工作。在混酸料中加入吸水性物质,可改善物料的稀糊状态,有利于后续工业化生产;将锂磷铝石煅烧后再混酸焙烧,可消除混酸料的稀糊状,锂提取率达97%以上;酸化时在280℃左右进行保温反应,能驱氟、降低硫酸锂溶液中的氟离子含量,氟可以回收;尾渣中AlPO_(4)有较高的回收价值。The extraction of lithium from amblygonite by the sulfuric acid method was studied.The results showed that when the mass ratio of ore to sulfuric acid was 1∶0.4,the roasting temperature was 780~820℃,and the mass ratio of leaching liquid to solid was 1.6∶1,the extraction rate of lithium could reach above 96%.The Al^(3+),Fe^(3+)and PO_(4)^(3-)impurities in the lithium sulfate solution could be completely removed by adjusting the pH value of NaOH to 12.The obtained lithium sulfate solution could be complexed with Ca^(2+)by EDTA and reacted with Na_(2)CO_(3) solution to obtain a battery grade lithium carbonate.The optimization process is mainly aimed at the two technological difficulties of dilute paste and fluorine disposal in the mixed acid material.Adding water absorbent materials into the mixed acid material can improve the thin paste state of the material,which is conducive to subsequent industrial production operations.After calcining amblygonite and then roasting it with mixed acid,the paste of mixed acid can be eliminated,and the extraction rate of lithium can reach more than 97%.During acidification,the thermal insulation reaction at approximately 280℃can displace fluorine and reduce the fluorine ion content in lithium sulfate solution,fluorine can be recovered,and the tail slag AlPO_(4)has a higher recovery value.

关 键 词：锂磷铝石 硫酸 提取 氧化锂 碳酸锂 

分 类 号：TF111.3[冶金工程—冶金物理化学] TF826.3