多孔陶瓷基锂离子吸附剂的制备及性能研究

Preparation and Adsorption Performance of Porous Ceramic-based Lithium Ion Adsorbent

摘要:

采用溶胶-凝胶法在不同条件下制备Li4Ti5O12，通过XRD分析寻找出制备Li4Ti5O12的理想条件。将高岭土、滑石粉、氧化铝和碳粉制备的多孔陶瓷在前驱体溶胶中进行浸渍负载，经干燥、煅烧制备得到多孔陶瓷基Li4Ti5O12，进行酸改性得到锂离子吸附剂，测定其对Li+的吸附容量。实验结果表明，在一定范围内提高煅烧温度和增加保温时间有利于Li4Ti5O12的生成，在750 ~ 800 ℃下保温5 ~ 8 h得到的产品结晶度好、晶相纯度高。洗脱率和吸附容量随着煅烧温度和保温时间的增加而增加，在800 ℃下保温5 h得到的样品经过酸洗后洗脱率为51.7 %，对Li+的吸附容量为12.2 mg Li+/g Li4Ti5O12。

Abstract:

Li4Ti5O12 was synthesized by the sol-gel process under different conditions, and the as-prepared products were characterized by XRD in order to find out the ideal condition of preparing Li4Ti5O12. The precursor sol was loaded on porous ceramics synthesized from kaolin, talcum powder, alumina and carbon powder, and then Li4Ti5O12 based on porous ceramics was prepared after drying and calcination. Subsequently, porous ceramic-based lithium ion adsorbent was obtained by modification with hydrochloric acid, and then adsorptive capacity of the obtained product was measured. The results indicate that increasing calcination temperature and holding time is beneficial to the formation of Li4Ti5O12. The products with good crystallinity and purified crystal phase are obtained after a calcination at 750 ~ 800 ℃ for 5 ~ 8 h. The extraction rate of Li+ from Li4Ti5O12 and the adsorptive capacity are increased with the increment of calcination temperature and holding time. The Li+ drawn out ratio of the products calcined at 800 ℃ for 5 h is 51.7 %, and the adsorptive capacity reaches 12.2 mg Li+/g Li4Ti5O12.