多孔钛系锂离子筛的制备和吸附过程研究  

Study on the Preparation and Adsorption Process of Porous Titanium Lithium-Ion Sieve

作　　者：马骏洲 王邹彪 姚浩然 陈亚 石西昌 MA Jun-zhou;WANG Zou-biao;YAO Hao-ran;CHEN Ya;SHI Xi-chang(School of Metallurgy and Environment,Central South University,Changsha 410083,China)

机构地区：[1]中南大学冶金与环境学院,长沙410083

出　　处：《离子交换与吸附》2025年第2期156-166,I0004,共12页Ion Exchange and Adsorption

摘　　要：偏钛酸锂(Li_(2)TiO_(3))型锂离子筛是一种性能优良的锂离子吸附剂,但是人工合成的Li_(2)TiO_(3)为粉状材料,在工业应用过程中存在难过滤、溶损高等问题,而利用悬浮造粒技术对粉体成型可以解决这些问题。文章以苯乙烯和二乙烯苯为聚合单体,甲苯为致孔剂,将经过硅烷修饰的粉状Li_(2)TiO_(3)造粒成型为具有多孔结构的粒状钛系锂离子筛;研究了该锂离子筛在不同条件下的吸附性能,并对其吸附过程进行了动力学和热力学拟合分析。结果显示,该多孔钛系锂离子筛的最佳吸附环境p H为11,在最佳吸附条件下的平衡吸附容量为5.47 mg/g;其吸附动力学过程符合准二阶动力学模型,等温吸附过程符合Langmuir模型,对Li^(+)的吸附过程是一种单层的化学吸附。在对玻利维亚盐湖卤水中的循环吸附实验中,其对Li^(+)的吸附表现出较强的选择性,Li^(+)与Mg^(2+)、Na^(+)的分离系数(α_(Mg)^(Li)和α_(Na^(Li)))分别为97.43和179.45,在多次循环吸附后仍然保持较为稳定的平衡吸附容量。Lithium metatitanate (Li_(2)TiO_(3)) type lithium-ion sieve is a high-performance lithium-ion adsorbent,but the synthesized Li_(2)TiO_(3) is a powder material,which has problems such as difficult filtration and high dissolution in industrial applications.The use of suspension granulation technology to shape the powder can solve these problems.This article utilizes styrene and divinylbenzene as polymerization monomers,with toluene as a porogen,to synthesize a porous,Li_(2)TiO_(3) lithium-ion sieve from silane-modified powder.The study thoroughly examined the adsorption performance of this lithium-ion sieve under various conditions and analyzed the adsorption process through kinetic and thermodynamic models.The findings revealed that the optimal p H for adsorption using this lithium-ion sieve is 11,achieving an equilibrium adsorption capacity of 5.47 mg/g under ideal conditions.The adsorption kinetics were best described by a pseudo-second-order model,while the isothermal adsorption process aligned with the Langmuir model,suggesting that lithium-ion adsorption occurs via monolayer chemical adsorption.In cyclic adsorption tests using brine from Bolivia's salt lakes,the sieve demonstrated strong selectivity for Li^(+),with selectivity coefficients of (α_(Mg)^(Li) and α_(Na^(Li))) being 97.43 and 179.45,respectively,and maintained stable adsorption capacity across multiple cycles.

关 键 词：偏钛酸锂 锂离子筛 造粒 动力学 热力学 

分 类 号：O647[理学—物理化学]