化工学报 ›› 2020, Vol. 71 ›› Issue (2): 879-888.DOI: 10.11949/0438-1157.20191484

• 材料化学工程与纳米技术 • 上一篇    下一篇

硝酸锂改性钛系离子筛的制备及其吸附性能

郭佳明1(),刘明言1,2(),吴强1,马永丽1   

  1. 1.天津大学化工学院,天津 300350
    2.化学工程联合国家重点实验室(天津大学),天津 300350
  • 收稿日期:2019-12-06 修回日期:2020-01-03 出版日期:2020-02-05 发布日期:2020-02-05
  • 通讯作者: 刘明言
  • 作者简介:郭佳明(1993—),男,硕士研究生, 1449382193@qq.com

Preparation and adsorption performance of titanium based lithium ion sieve improved by LiNO 3

Jiaming GUO1(),Mingyan LIU1,2(),Qiang WU1,Yongli MA1   

  1. 1.School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
    2.State Key Laboratory of Chemical Engineering (Tianjin University), Tianjin 300350, China
  • Received:2019-12-06 Revised:2020-01-03 Online:2020-02-05 Published:2020-02-05
  • Contact: Mingyan LIU

摘要:

钛系锂离子筛具有较高的锂吸附容量和稳定性,对其制备工艺及性能进行改进研究具有重要意义。使用硝酸锂和碳酸锂混合物作为锂源,与二氧化钛在500℃下进行固相反应,生成层状钛酸锂;使用0.2 mol·L -1盐酸对其酸洗24 h,得到了锂离子筛吸附剂;采用X射线衍射、扫描电镜、粒度分析、N 2吸附-脱附方法等,对其性能进行了表征;通过锂离子的吸附实验,确定了吸附和再生性能;探究了该新型吸附剂的锂离子吸附机理。结果表明:吸附过程是单分子层化学吸附;经过改性,离子筛颗粒更加细小,孔体积和比表面积更大,结构完整;在70 mg·L -1的Li +溶液中,吸附量为25.01 mg·g -1,准二级吸附速率常数为0.2762 g·(mg·h) -1,吸附速率较之未改性提高了54.56%;该离子筛对浓度为11.6 mg·L -1的Li +溶液,其锂去除率可以达到99.77%。

关键词: 吸附剂, 动力学模型, 颗粒, 锂离子筛, 固相反应, 硝酸锂

Abstract:

Titanium based lithium ion sieves have excellent lithium adsorption capacity and stability, and the improvement studies on its preparation and character are of great importance. A mixture of LiNO 3 and Li 2CO 3was used as the lithium source to synthesize laminar Li 2TiO 3 through the solid state reaction at 500℃, and lithium ion sieves were prepared after being put it in 0.2 mol·L -1 hydrochloric acid pickling solution for 24 h. Physicochemical properties of the ion sieves were characterized by X-ray diffraction (XRD), scanning electronmicroscopy (SEM), particle size distribution analysis and nitrogen adsorption-desorption measurements. Adsorption, regeneration properties of the ion sieves and adsorption mechanism were investigated. It is revealed that adsorption process conforms to the monomolecular and chemical adsorption. Furthermore, micro-scale particles with higher pore volume and higher specific area were obtained after modification. Adsorption capacity and pseudo-second-order kinetic constant of 25.01 mg·g -1 and 0.2762 g·(mg·h) -1, respectively, were obtained by pouring the lithium ion sieves in the solution of 70 mg·L -1 for 24 h. Hence, the increase in adsorption rate of 54.56% was observed. The removal rate of Li + (99.77%) can be reached using this ion sieves in the solution of concentration of 11.6 mg·L -1.

Key words: adsorbents, kinetic modeling, particle, lithium ion sieve, solid state reaction, LiNO 3

中图分类号: