无机沉淀胶溶法制备钛锂离子筛及其吸附性能研究

Preparation of Titanium-lithium Ion Sieve by the Inorganic Precipitation-peptization Method and Its Adsorption Performance

以硫酸钛、乙酸锂为主要原料,采用无机沉淀胶溶法制备了偏钛酸型钛锂离子筛。采用BET、XRD、XPS和ICP-OES对样品的比表面积、孔结构、晶相组成、化学元素组成、溶液中Li^+及Ti4^+的浓度进行测试,并研究了其吸附等温线和吸附动力学行为。结果表明:加入十二烷基苯磺酸钠(SDBS)后,产物的介孔结构数量增加,孔容明显增大,比表面积也有效增大;与Langmuir吸附模型相比,吸附剂的吸附方式更符合Freundlich吸附模型,说明吸附剂对Li+的吸附并非单层吸附;吸附动力学过程符合伪二级动力学模型,说明吸附方式为化学吸附。

H2TiO 3-titanium-lithium adsorbent was prepared with titanium sulfate and lithium acetate as main materials via inorganic precipitation-peptization method. The specific surface area,pore structure,crystal phase,composition of chemical elements and concentrations of Li^+ and Ti^4+ were decided by BET,XRD,XPS and ICP-OES,respectively. The adsorption isotherm and kinetics were also studied. The results indicated that the number of mesoporous structure,the pore volume and the specific surface area of the product increased effectively after the addition of sodium dodecyl benzene sulfonate (SDBS). The adsorption of lithium ion by the adsorbent accorded better with the Freundlich model as compared with the Langmuir model,which indicated that the adsorption of Li^+ was not monolayer adsorption. The kinetic process of adsorption was coincident with the pseudo-second-order kinetic model,indicating that the adsorption style was chemical adsorption.