铬铁复合掺杂锂离子筛的制备及其吸附性能研究  

Study on preparation and adsorption performance ofchromium-iron composite doped lithium-ion sieve

作　　者：李珍 高建明 赵茜 郭彦霞 LI Zhen;GAO Jianming;ZHAO Qian;GUO Yanxia(Institute of Resources and Environmental Engineering,Shanxi University,Taiyuan 030006,China;State Environmental Protection Key Laboratory on Efficient Resource-utilization Techniques ofCoal Waste,Shanxi University,Taiyuan 030006,China)

机构地区：[1]山西大学资源与环境工程研究所,太原030006 [2]山西大学国家环境保护煤炭废弃物资源化高效利用重点实验室,太原030006

出　　处：《功能材料》2024年第4期4094-4101,共8页Journal of Functional Materials

基　　金：国家自然科学基金区域创新项目(U21A20321);吕梁市校地合作科技成果转化推广项目(2022XDHZ15)。

摘　　要：利用具有选择性高、吸附容量大、吸附速率快的锂离子筛从低浓度液相中吸附和分离锂已成为最有前途的方法之一,但锂锰氧化物锂离子筛因其Mn溶损率大、循环性能差在工业应用中受到限制。以LiOH·H_(2)O、MnO_(2)、Fe_(2)O_(3)、Cr_(2)O_(3)为原料,通过高温固相法制备了尖晶石型铬铁复合掺杂锂离子筛。重点研究了Cr掺杂量和煅烧温度对锂离子筛结构、吸附性能和Mn溶损率的影响。结果表明,当锂、锰、铁、铬的摩尔比为1∶2∶0.05∶0.05、煅烧温度为550℃时,合成的锂离子筛饱和吸附容量为27.30 mg/g, Mn溶损率仅为0.43%。选择吸附实验表明该锂离子筛对Li~+具有优异的选择性能。此外,经过5次循环实验后,铬铁复合掺杂锂离子筛的饱和吸附容量仍能保持第二次循环的89%,为18.51 mg/g,优于未掺杂锂离子筛的56%。The Li+adsorption and separation from low concentration solution by lithium-ion sieve has become one of the most promising methods due to the high selectivity,adsorption capacity and adsorption rate towards lithium ion(Li+).However,the industrial application of lithium manganese oxide ion-sieve is limited due to its difficult recovery,high Mn dissolution loss rate and poor circulation performance.In this paper,the spinel-structure chromium-iron composite doped lithium-ion sieves were prepared by high-temperature solid state reaction method usingLiOH·H 2O,MnO_(2),Fe 2O_(3),and Cr 2O_(3) as raw materials.The effects of Cr doping amounts and calcination temperature on the phase structure,adsorption performance,and Mn dissolution loss rate of the lithium-ion sieve precursors were investigated.The results showed that the adsorption capacity of the synthesized lithium-ion sieve could reach 27.30 mg/g and the Mn dissolution loss rate was only 0.43%when the molar ratio of Li,Mn,Fe and Cr was 1∶2∶0.05∶0.05 and the calcination temperature was 550℃.The selection adsorption experiments showed that the lithium-ion sieve presents excellent selection performance for Li+.Furthermore,the recycling performance of chromium-iron doped lithium-ion sieve showed that the adsorption capacity could still remain 89%of the second cycle(18.51 mg/g)after five cycles,which is greater than 56%of the undoped lithium-ion sieve.

关 键 词：锂离子筛 复合掺杂 锂锰氧化物 尖晶石 吸附 选择性 

分 类 号：TQ424.2[化学工程]