固相法合成高效锂离子筛及其性能研究  

Synthesis of high-efficiency lithium ion sieve by solid-phase method and its performance

作　　者：彭珊 石瑀 章佳豪 王乾坤 谢洪珍 许晓阳 PENG Shan;SHI Yu;ZHANG Jiahao;WANG Qiankun;XIE Hongzhen;XU Xiaoyang(State Key laboratory of Comprehensive Utilization of Low-Grade Refractory Gold Ores,Xiamen 361101,China;Xiamen Zijin Mining and Technology Co.,Ltd.,Xiamen 361101,China)

机构地区：[1]低品位难处理黄金资源综合利用国家重点实验室,福建厦门361101 [2]厦门紫金矿冶技术有限公司,福建厦门361101

出　　处：《中国有色冶金》2025年第1期105-113,共9页China Nonferrous Metallurgy

基　　金：国家科技项目-中央引导地方科技发展专项(2022L3095)。

摘　　要：针对钛系锂离子筛在实际应用中锂吸附容量低、吸附速率慢和吸附剂稳定性差等问题,本文以碳酸锂、二氧化钛、乙酸锂为原料,采用改进高温固相法合成锂离子筛,对合成后的锂离子筛前驱体的表观形貌、晶相组成等进行了表征,并以国内某盐湖卤水为原料,开展锂离子筛性能测试,着重考察了锂离子筛的杂质离子选择性、循环吸附性能及钛溶损原因,得到以下主要结论。锂离子筛前驱体较优制备工艺条件为合成煅烧温度699℃、■比值0.45、煅烧时间24 h,■比值0.2:1,此时锂离子筛对卤水的最大饱和吸附量为27.42 mg/g;经多次循环吸附-解吸试验后,锂离子筛工作吸附量为8 mg/g(市面吸附剂30 min吸附量均为6 mg/g左右),Li^(+)解吸率约85%;杂质离子选择性较好,Li/Na=4.5、Li/K=25、Li/Mg=13、Li/Ca=40,杂质离子分离系数排序为α_(Li/K)>α_(Li/Mg)>α_(Li/Na)>α_(Li/Ca);锂离子筛中钛的溶出属于偏钛酸锂结构性溶出。In response to the challenges posed by low lithium adsorption capacity,slow adsorption rates,and poor stability of titanium-based lithium ion sieves in practical applications,this study synthesizes a lithium ion sieve utilizing lithium carbonate,titanium dioxide,and lithium acetate as raw materials through an improved high-temperature solid-state method.The synthesized precursor of the lithium ion sieve was characterized with respect to its morphological appearance and crystalline phase composition.Performance tests were conducted using brine sourced from a domestic salt lake as the raw material,focusing on selectivity for impurity ions,cyclic adsorption performance,and the mechanisms underlying titanium leaching.The following key conclusions were drawn:The optimal preparation conditions for the precursor of the lithium ion sieve include a calcination temperature of 699 ℃,a ■ ratio of 0.45,a calcination time of 24 h,and an ■ ratio of 0.2:1.Under these conditions,the maximum saturated adsorption capacity for brine reached 27.42 mg/g;after multiple cycles of adsorption-desorption tests,the working adsorption capacity was determined to be 8 mg/g(in comparison to approximately 6 mg/g for commercially available adsorbents with a 30-minute adsorption period),with an Li~+ desorption rate around 85%.The selectivity towards impurity ions is relatively favorable with ratios such as Li/Na=4.5,Li/K=25,Li/Mg=13,and Li/Ca=40;thus indicating that separation coefficients rank as α_(Li/K)>α_(Li/Mg)>α_(Li/Na)>α_(Li/Ca).Furthermore,the leaching of titanium from the lithium ion sieve is attributed to structural dissolution associated with lithia-titanate formation.

关 键 词：锂离子筛 吸附容量 吸附剂稳定性 吸附速率 助熔剂 离子选择性 溶损 

分 类 号：TF826.3[冶金工程—有色金属冶金] TF803.9