CIESC Journal ›› 2024, Vol. 75 ›› Issue (4): 1616-1629.DOI: 10.11949/0438-1157.20231276

• Separation engineering • Previous Articles     Next Articles

Adsorption properties of functionalized porous carbon nitride materials for uranium

Yuan MENG1,2(), Shan NI2(), Yafeng LIU2,3, Wenjie WANG2,3, Yue ZHAO2,3, Yudan ZHU1, Liangrong YANG2,3()   

  1. 1.State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 211816, Jiangsu, China
    2.Key Laboratory of Green and High-end Utilization of Salt Lake Resources, State Key Laboratory of Petroleum Molecular & Process Engineering (RIPP, SINOPEC), CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
    3.School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2023-12-04 Revised:2024-01-12 Online:2024-06-06 Published:2024-04-25
  • Contact: Shan NI, Liangrong YANG

功能化多孔氮化碳材料对铀的吸附性能研究

孟园1,2(), 倪善2(), 刘亚锋2,3, 王文杰2,3, 赵越2,3, 朱育丹1, 杨良嵘2,3()   

  1. 1.南京工业大学化工学院材料化学工程国家重点实验室,江苏 南京 211816
    2.中国科学院过程工程研究所盐湖资源绿色 高值利用重点实验室,石油化工分子转化与反应工程全国重点实验室,中国科学院绿色过程与工程重点实验室,北京 100190
    3.中国科学院大学化学工程学院,北京 100049
  • 通讯作者: 倪善,杨良嵘
  • 作者简介:孟园(1998—),男,硕士研究生,mengy925@163.com
  • 基金资助:
    国家重点研发计划项目(2021YFC2901500);国家自然科学基金项目(22138012);中国科学院稳定支持基础研究领域青年团队项目(YSBR-038);中国科学院青年创新促进会优秀会员项目(Y202014);中国博士后科学基金项目(2023M733521)

Abstract:

The separation and enrichment of uranium from seawater and wastewater is of great significance to the sustainable development of energy and environmental protection. A porous carbon nitride adsorbent (d-g-CN) rich in cyano groups and hydroxyl groups was prepared through one-step alkalization and heat-condensation polymerization of melamine, and its adsorption performance for uranium was studied. The results of adsorption experiments showed that under the conditions of pH=6.0 and 298 K, the adsorption of uranium by d-g-CN reached equilibrium in about 3 h, and the saturated adsorption capacity was 2476.23 mg∙g-1. The adsorption process conformed to the pseudo second order kinetic model and Freundlich isotherm model. In addition, d-g-CN had excellent selectivity and cyclicity. When there were many competitive ions in the solution, the adsorption distribution coefficient of d-g-CN for uranium reached 1.48×104 ml∙g-1. The adsorption efficiency remained about 89.5% after six cycles. Because the large specific surface area of d-g-CN provided more adsorption sites, and functional groups of cyano and hydroxyl had coordination effect with uranium, d-g-CN showed excellent adsorption performance, and had certain application potential in the extraction of low concentration uranium.

Key words: carbon nitride, uranium, seawater, waste water, adsorption, selectivity

摘要:

从海水和废水中分离和富集铀对能源的可持续发展和保护环境具有重要意义。通过一步碱化和热缩聚三聚氰胺制备了一种富含氰基和羟基的多孔氮化碳吸附剂(d-g-CN),研究其对铀的吸附性能。吸附实验结果表明,在pH=6.0和298 K的条件下,d-g-CN对铀的吸附在3 h达到吸附平衡,饱和吸附容量为2476.23 mg∙g-1。吸附过程符合拟二级动力学模型和Freundlich等温模型。此外,d-g-CN具有优异的选择性和循环性,在溶液中存在多种竞争离子时,d-g-CN对铀的吸附分配系数达到1.48×104 ml∙g-1,并且6次循环后吸附效率仍保持在89.5%。由于d-g-CN较大的比表面积提供了更多的吸附位点,同时氰基和羟基等功能基团与铀存在配位作用,因此d-g-CN表现出优异的吸附性能,在低浓度铀的提取方面具有一定的应用潜力。

关键词: 氮化碳, 铀, 海水, 废水, 吸附, 选择性

CLC Number: