Li Ziyi, Li Jun, Rong Huazhen, Zuo Jiayu, Yang Xiong, Xing Yi, Liu Yingshu, Zhu Guangshan, Zou Xiaoqin
School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, P. R. China.
Beijing Higher Institution Engineering Research Center of Energy Conservation and Environmental Protection, Beijing 100083, P. R. China.
J Am Chem Soc. 2022 Apr 20;144(15):6687-6691. doi: 10.1021/jacs.2c01635. Epub 2022 Apr 6.
The molecular state is crucial for precise gas separation using a zeolite membrane, yet the state control remains a big challenge. Herein, we report a NO dimerization facilitated high performance SO/NO separation on a SSZ-13 zeolite membrane. The NO dimerization is triggered by temperature and pressure to form NO with big molecular size, and NO diffusion into the zeolite pore is inhibited on the basis of size exclusion, leading to high separation selectivity. Consequently, SO rather than NO preferentially permeates through the SSZ-13 membrane with a high SO permeance of 2 × 10 mol m s Pa and high SO/NO separation factor of 22, ∼50-fold of that measured without dimerization. The dimerization effect for SO/NO separation prevails in other small-pore zeolites such as NaA. This advanced function is revealed through membrane separation using single and mixture gases.
分子状态对于使用沸石膜进行精确的气体分离至关重要，但状态控制仍然是一个巨大的挑战。在此，我们报道了一种通过NO二聚化促进在SSZ-13沸石膜上实现高性能SO₂/NO分离的方法。NO二聚化由温度和压力触发，形成大分子尺寸的N₂O₂，基于尺寸排阻，N₂O₂扩散进入沸石孔受到抑制，从而实现高分离选择性。因此，SO₂而非NO优先透过SSZ-13膜，SO₂渗透率高达2×10⁻⁷ mol m⁻² s⁻¹ Pa⁻¹，SO₂/NO分离因子高达22，约为未发生二聚化时测量值的50倍。SO₂/NO分离的二聚化效应在其他小孔径沸石如NaA中也很显著。这种先进功能通过使用单一气体和混合气体的膜分离得以揭示。
