溶胶-凝胶法制备的偏钛酸型锂离子吸附剂模拟从盐湖卤水中吸附Li^+研究（英文）

Simulative adsorption of Li^+ from the saline lake brine by the H_2TiO_3-lithium adsorbent synthesized by the sol-gel process

本文以钛酸丁酯和乙酸锂为钛源和锂源,采用溶胶-凝胶法制备了钛酸锂(Li_2TiO_3)纳米粒子,用盐酸对其进行处理得到偏钛酸型锂离子吸附剂(钛锂离子筛).配制了盐湖卤水模拟液,在吸附之前向模拟液中加入氢氧化钠除去Mg^(2+)和Ca^(2+),并用所制备的吸附剂进行了模拟从盐湖卤水中吸附锂离子的研究.结果表明偏钛酸型锂离子吸附剂对锂离子的吸附容量为8.25mg·g^(-1),Li^+的分配系数(Kd)为24.54 mL·g^(-1),其数值远大于Na^+(0.52 mL·g^(-1))和K+(0.97mL·g^(-1))的分配系数.Li^+对Na^+的分离因素(αLiNa)为47.2,Li^+对K^+的分离因素(αLiK)为25.3,表明所制备的吸附剂对Li^+具有很好的选择吸附性.

The Li2TiO3 nanoparticles were prepared by the sol-gel process by employing lithium acetate and tetrabutyl titanate as lithium and titanium sources, respectively, followed by modification with hydrochloric acid to obtain H2TiO3-1ithium adsorbent （titanium lithium ionic sieve）. Simulation of the saline lake brine was prepared, followed by adding sodium hydroxide to the prepared solution before adsorption to remove Mg2＋ as well as Ca2＋. Simulative adsorption of Li＋ by the obtained adsorbent from the saline lake brine was carried out. The results indicate that the adsorption capacity of H2 TiO3-1ithium adsorbent for Li＋ is 8.25 mg· g-1, and the partition coefficient （Ka） of Li＋ is calculated to be 24.54 mL · g-1, which is much larger than that of Na＋（0.52 mL· g-l） and K＋（0.97 mL · g-l）. Li＋ to Na＋ separation factor （aNa）u is 47.2, and Li＋ to K＋ separation factor （ak^Li） is 25.3, indicating that the synthesized adsorbent has an excellent selective adsorption performance to Li＋.