SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2023, Vol. 57 ›› Issue (5): 319-328.DOI: 10.1016/j.cjche.2022.09.001

• Full Length Article • 上一篇    下一篇

Selective capture of silver ions from aqueous solution by series of azole derivatives-functionalized silica nanosheets

Shanshan Mao1, Tao Shen1, Qing Zhao1, Tong Han2, Fan Ding1, Xin Jin1, Manglai Gao1   

  1. 1. State Key Laboratory of Heavy Oil Processing, College of Science, China University of Petroleum, Beijing 102249, China;
    2. Unconventional Natural Gas Institute, China University of Petroleum, Beijing 102249, China
  • 收稿日期:2022-04-28 修回日期:2022-08-30 出版日期:2023-05-28 发布日期:2023-07-08
  • 通讯作者: Manglai Gao,E-mail:mlgao@cup.edu.cn
  • 基金资助:
    The support to this work from the National Natural Science Foundation of China (21776306) is acknowledged.

Selective capture of silver ions from aqueous solution by series of azole derivatives-functionalized silica nanosheets

Shanshan Mao1, Tao Shen1, Qing Zhao1, Tong Han2, Fan Ding1, Xin Jin1, Manglai Gao1   

  1. 1. State Key Laboratory of Heavy Oil Processing, College of Science, China University of Petroleum, Beijing 102249, China;
    2. Unconventional Natural Gas Institute, China University of Petroleum, Beijing 102249, China
  • Received:2022-04-28 Revised:2022-08-30 Online:2023-05-28 Published:2023-07-08
  • Contact: Manglai Gao,E-mail:mlgao@cup.edu.cn
  • Supported by:
    The support to this work from the National Natural Science Foundation of China (21776306) is acknowledged.

摘要: The introduction of bifunctional groups into low-cost adsorbents for selective adsorption of Ag(I) through synergistic effect will have a profound impact on the recovery of precious metals. Organo silica nanosheets (organo-SiNSs) functionalized by series of azole derivatives (2-mercaptoimidazole (MI), 2-mercaptobenzimidazole (MBT) and 1H-1,2,4-triazole-3-thiol (MTT)), are fabricated and employed for selective removal of Ag(I). The structures of the organo-SiNSs are investigated using several characterization methods. The results of batch adsorption experiments display that the maximum adsorption amounts are 70.3, 103.2 and 139.5 mg·g-1 on MI-SiNSs, MBI-SiNSs and MTT-SiNSs for Ag(I) ions, and reach rapid equilibrium within 10–30 min. The adsorption processes are chemisorption and fit pseudo-second-order kinetic model and Langmuir adsorption isotherm model. Notably, MTT-SiNSs is greatly selective for Ag(I) in multicomponent system, and the distribution coefficient value of Ag(I) ions reaches 2331.26 ml·g-1. The reusability of organo-SiNSs is verified by four cycles of regeneration tests with 0.1 mol·L–1 HNO3 as the eluent. A combination of experimental, structural along with theoretical analysis is conducted to proclaim the structure-adsorptivity relationship: (i) The adsorption mechanisms are attributed to complexation. (ii) The amino group and sulfhydryl group of MTT-SiNSs as well as MBI-SiNSs may have synergistic impacts on Ag(I) capture. (iii) The differences in adsorption behavior and selectivity of the three organo-SiNSs are mainly related to the form of function groups, charge density and steric hindrance of adsorbent. This work not only sheds light on the promise of functionalized organo-SiNSs for the rapid and selective removal/enrichment of Ag(I) ions in complex water systems, but also provides new insights for designing cost-effective SiNSs-based adsorbents.

关键词: Organo silica nanosheets, Adsorption, Silver ions, Selectivity, Mechanism, Waste treatment

Abstract: The introduction of bifunctional groups into low-cost adsorbents for selective adsorption of Ag(I) through synergistic effect will have a profound impact on the recovery of precious metals. Organo silica nanosheets (organo-SiNSs) functionalized by series of azole derivatives (2-mercaptoimidazole (MI), 2-mercaptobenzimidazole (MBT) and 1H-1,2,4-triazole-3-thiol (MTT)), are fabricated and employed for selective removal of Ag(I). The structures of the organo-SiNSs are investigated using several characterization methods. The results of batch adsorption experiments display that the maximum adsorption amounts are 70.3, 103.2 and 139.5 mg·g-1 on MI-SiNSs, MBI-SiNSs and MTT-SiNSs for Ag(I) ions, and reach rapid equilibrium within 10–30 min. The adsorption processes are chemisorption and fit pseudo-second-order kinetic model and Langmuir adsorption isotherm model. Notably, MTT-SiNSs is greatly selective for Ag(I) in multicomponent system, and the distribution coefficient value of Ag(I) ions reaches 2331.26 ml·g-1. The reusability of organo-SiNSs is verified by four cycles of regeneration tests with 0.1 mol·L–1 HNO3 as the eluent. A combination of experimental, structural along with theoretical analysis is conducted to proclaim the structure-adsorptivity relationship: (i) The adsorption mechanisms are attributed to complexation. (ii) The amino group and sulfhydryl group of MTT-SiNSs as well as MBI-SiNSs may have synergistic impacts on Ag(I) capture. (iii) The differences in adsorption behavior and selectivity of the three organo-SiNSs are mainly related to the form of function groups, charge density and steric hindrance of adsorbent. This work not only sheds light on the promise of functionalized organo-SiNSs for the rapid and selective removal/enrichment of Ag(I) ions in complex water systems, but also provides new insights for designing cost-effective SiNSs-based adsorbents.

Key words: Organo silica nanosheets, Adsorption, Silver ions, Selectivity, Mechanism, Waste treatment