化学学报 ›› 2020, Vol. 78 ›› Issue (3): 250-255.DOI: 10.6023/A19120449 上一篇    下一篇

研究论文

MIL-101(Cr)/GO复合吸附剂的O2/N2分离性能研究

刘洋a,b, 夏潇潇a,b, 谭媛元a,b, 李松a,b   

  1. a 华中科技大学能源与动力工程学院 煤燃烧国家重点实验室 武汉 430074;
    b 华中科技大学中欧清洁与可再生能源学院 武汉 430074
  • 投稿日期:2019-12-26 发布日期:2020-02-24
  • 通讯作者: 李松 E-mail:songli@hust.edu.cn
  • 基金资助:
    项目受国家自然科学基金面上项目(No.51672097)和中欧清洁与可再生能源学院双一流研究生教学平台培育基金(No.ICARE-RP-2018-HYDRO-001)资助.

O2/N2 Separation Performance of MIL-101(Cr)/Graphene Oxide

Liu Yanga,b, Xia Xiaoxiaoa,b, Tan Yuanyuana,b, Li Songa,b   

  1. a State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074;
    b China-EU Institute for Clean and Renewable Energy, Huazhong University of Science and Technology, Wuhan 430074
  • Received:2019-12-26 Published:2020-02-24
  • Supported by:
    Project supported by the National Natural Science Foundation of China (No. 51672097) and the Double First-class Research Funding of China-EU Institute for Clean and Renewable Energy (No. ICARE-RP-2018-HYDRO-001).

变压吸附(PSA)制取O2的核心是吸附剂.近年来,金属有机骨架(MOFs)被认为是一种具有广阔应用前景的新型吸附剂.通过水热法制备了MIL-101(Cr)/氧化石墨烯(GO).结果表明,MIL-101(Cr)/GO-15具有更高的比表面积(3486 m2·g-1)和更大的孔体积(2.39 cm3·g-1),因此也表现出更高的O2吸附量(0.54 mmol·g-1).进一步根据理想吸附溶液理论(IAST)预测了其在O2/N2体积比为1:4混合气体中的O2/N2选择性为1.2,相比MIL-101(Cr)提高了17.65%.同时,MIL-101(Cr)/GO-15的循环利用性能更佳,经过三次O2吸脱附循环后,依然拥有高达80%的O2吸附量,具有较好的循环再生性能.

关键词: O2/N2分离, 金属有机骨架, MIL-101(Cr)/GO, 循环再生性能

The pressure-swing adsorption (PSA) technology is the promising approach for O2/N2 separation because of its low cost and facile manipulation, in which adsorbents dominate the separation performance. In recent years, metal-organic frameworks (MOFs) have been recognized as the most potential adsorbents in gas adsorption and separation due to their ultrahigh surface area. In this work, MIL-101(Cr) with different weight percentages of graphene oxide (5%, 15% and 35%) was prepared by growing MIL-101(Cr) on pre-synthesized GO materials. The final product was activated under vacuum at 180℃ for 12 h. Structure characterization of different MIL-101(Cr)/GO composites revealed that MIL-101(Cr)/GO-15 with 15% GO additive exhibited the highest specific surface area (3486 m2·g-1) and pore volume (2.39 cm3·g-1) compared with pristine MIL-101(Cr) and the composites with 5% and 35% GO additives. The high surface area and pore volume are beneficial for the O2 uptake of MIL-101(Cr)/GO-15. Compared with the O2 uptake of MIL-101(Cr)/GO-5 (0.35 mmol·g-1) and MIL-101(Cr)/GO-35 (0.31 mmol·g-1), MIL-101(Cr)/GO-15 exhibited the highest uptake of 0.54 mmol·g-1. Further pore size distribution analysis demonstrated that the enhanced O2 uptake of MIL-101(Cr)/GO-15 can be ascribed to its increased fraction of mesopores. On the other hand, O2/N2 selectivity of different MIL-101(Cr)/GO composites was also calculated according to ideal adsorbed solution theory (IAST), from which it was found that MIL-101(Cr)/GO-15 displayed the highest O2/N2 selectivity (1.2) in a binary gas mixture with the volume fraction of O2/N2=1/4. Compared with pristine MIL-101, O2/N2 selectivity of MIL-101(Cr)/GO-15 was increased by 17.65%. Recyclability is one of the most important criteria to evaluate the gas adsorption performance of adsorbents. Therefore, the recyclability of MIL-101(Cr)/GO-15 was tested by measuring the O2 adsorption and desorption isotherms for three cycles. It was revealed that 80% of O2 uptake of MIL-101(Cr)/GO-15 was remained after three adsorp-tion/desorption cycles, implicating the outstanding recyclability of MIL-101(Cr)/GO-15.

Key words: O2/N2 separation, metal-organic framework, MIL-101(Cr)/GO, recyclability