钛纳米管的制备和对铀离子的吸附

Synthesis and Adsorptive Removal for Uranium(Ⅵ)Ions of Titanate Nanotubes

以钛酸丁酯为钛源采用水热法制备钛纳米管,用透射电镜和X射线衍射分析(XRD)表征材料的形貌和组成以及N_2吸附/脱附比表面积的测试,研究了钛纳米管对铀离子的吸附。结果表明,钛纳米管的外径为8 nm,管长度达2μm,由Na_2Ti_3O_7与H_3Ti_3O_7共存组成;吸附铀容量随着温度的升高、震荡时间的增加平缓升高,最大吸附pH值为5,饱和吸附容量达62.9 mg/g,吸附等温线符合Langmuir和Freundlich等温吸附模型。热力学研究表明,该吸附是吸热自发过程,回收率随着铀量的增加而逐步减小,吸附铀的钛纳米管比未吸附铀的比表面积小.

Titanate nanotubes have been synthesized by a hydrothermal method using tetrabutyl as titanium source.The prepared sodium titanate nanotubes were applied in the adsorption of uranium ions. The determination of the structure of the materials by TEM and XRD showed that titanate nanotubes compose of Na_2Ti_3O_7 and H_3Ti_3O_7 with external diameter of 8 nm,tube length up to 2μm.The investigation of adsorption of uranium ions demonstrated that adsorption capacity growed gradually with the increase of temperature and shock time,and achieved maximum adsorption capacity at pH 5.5.The adsorption isotherm accorded with Langmuir and Freundlich matrix.Thermodynamic studies showed that the adsorption is endothermic spontaneous process.The recovery studies showed that the recovery graduately decrease with the increasing of uranium content.N_2 adsorption/desorption tests found that the surface area of titanate nanotubes adsorbed uranium ions were smaller than previous.