Acta Chimica Sinica ›› 2022, Vol. 80 ›› Issue (7): 879-887.DOI: 10.6023/A22020074 Previous Articles     Next Articles



刘芳a, 潘婷婷a, 任秀蓉a,b, 鲍卫仁a,b,c, 王建成a,b, 胡江亮a,b,c,*()   

  1. a 太原理工大学 省部共建煤基能源清洁高效利用国家重点实验室 太原 030024
    b 太原理工大学 煤科学与技术教育部重点实验室 太原 030024
    c 山西浙大新材料与化工研究院 太原 030024
  • 投稿日期:2022-02-18 发布日期:2022-05-05
  • 通讯作者: 胡江亮
  • 基金资助:
    山西省应用基础研究计划重点自然基金项目(201901D111003(ZD)); 山西浙大新材料与化工研究院研发项目(2021SX-TD007)

Research on Preparation and Benzene Adsorption Performance of HCDs@MIL-100(Fe) Adsorbents

Fang Liua, Tingting Pana, Xiurong Rena,b, Weiren Baoa,b,c, Jiancheng Wanga,b, Jiangliang Hua,b,c()   

  1. a State Key Laboratory of Clean and Efficient Coal Utilization, Taiyuan University of Technology, Taiyuan 030024
    b Key Laboratory of Coal Science and Technology, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024
    c Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering, Taiyuan 030024
  • Received:2022-02-18 Published:2022-05-05
  • Contact: Jiangliang Hu
  • Supported by:
    Shanxi Province Science Foundation for Key Program(201901D111003(ZD)); Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(2021SX-TD007)

Benzene is a typical volatile organic compound with high photochemical reaction activity, which can seriously harm the environment and human health. Adsorption is an effective method to remove volatile organic compounds (VOCs), and the core of the adsorption method is the development of adsorbents. The high specific surface area and pore volume of metal-organic frameworks (MOFs) make them useful in the field of VOCs adsorption. However, the presence of water lead to a decrease in the adsorption capacity of MOFs. In this work, hydrophobic carbon dots (HCDs)@MIL-100(Fe)-Cx composites were prepared by in situ synthesis of hydrophobic carbon dots with MIL-100(Fe) to improve their benzene adsorption performance. The composite adsorbents were characterized by powder X-ray diffraction (PXRD), N2 adsorption-desorption, thermal gravimetric (TG), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and transmission electron microscope (TEM), the static adsorption capacity of HCDs@MIL-100(Fe)-Cx for benzene and water was determined by gravimetric vapor adsorption analyzer, the dynamic adsorption performance of benzene was investigated by measuring the breakthrough curve of the fixed bed. The results showed that the HCDs were compounded with MIL-100(Fe) by loading or embedding, and the specific surface area of the compounded materials increased significantly and possessed hierarchical pores. The synergistic adsorption of HCDs and MIL-100(Fe) greatly enhanced the adsorption capacity of benzene and the competitive adsorption selectivity of benzene/water. At 25 ℃, when the relative pressure was 0.9, the benzene adsorption capacity of HCDs@MIL-100(Fe)-C1 was 2.9 times that of MIL-100(Fe). When the relative pressure was 0.1, the adsorption capacity of HCDs@MIL-100(Fe)-C1 for benzene was increased by 175.66 mg/g compared with MIL-100(Fe), while the adsorption capacity for water was only increased by 16.87 mg/g, and the competitive adsorption selectivity of HCDs@MIL-100(Fe)-C1 was up to 3.4, while the highest for MIL-100(Fe) was only 2.4. Water contact angle experiments confirmed that HCDs improved the hydrophobicity of MIL-100(Fe). The ability of the composite to capture low concentration of benzene was enhanced; the dynamic breakthrough time of HCDs@MIL-100(Fe)-C1 was 1.4 times that of MIL-100(Fe), and it has perfect cyclic stability. Therefore, HCDs@MIL-100(Fe)-Cx has reference significance for the preparation of adsorbents with high VOCs adsorption performance.

Key words: metal-organic frameworks (MOFs), adsorption, hydrophobicity, carbon dots, in situ composite