Hirota Yuichiro, Nakai Masaki, Tani Kasumi, Sakane Koya, Ikeda Ayumi, Hasegawa Yasuhisa, Araki Sadao
Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan.
National Institute of Advanced Industrial Science and Technology (AIST), Research Institute for Chemical Process Technology, 4-2-1 Nigatake, Miyagino-ku, Sendai 983-8551, Japan.
Membranes (Basel). 2025 Mar 1;15(3):70. doi: 10.3390/membranes15030070.
NaZSM-5 powder and membranes were hydrothermally prepared. Their (1) steam (HO) adsorption properties and (2) the permeation and separation of gas and HO were evaluated before and after the cation exchange of Na to K or Cs. The quantity of adsorbed HO decreased as the size of the cation increased, indicating that the micropore volume and effective pore size of ZSM-5 decreased after cation exchange. The H and N permeances after cation exchange were less than 5% of the values before cation exchange, indicating a significant reduction in gas permeability. In contrast, the reduction of the HO permeance values of the ZSM-5 membranes before and after K or Cs exchange was lower than that of H, resulting in improved HO/H separation performance. Compared with the NaZSM-5 membrane, the K- or Cs-exchanged ZSM-5 membranes exhibited superior HO permselectivity, particularly at dilute HO concentrations (<1 vol%).
采用水热法制备了NaZSM-5粉末和膜。在将Na阳离子交换为K或Cs之前和之后，分别对它们的（1）蒸汽（H₂O）吸附性能以及（2）气体和H₂O的渗透与分离性能进行了评估。随着阳离子尺寸的增大，吸附的H₂O量减少，这表明阳离子交换后ZSM-5的微孔体积和有效孔径减小。阳离子交换后的H₂和N₂渗透通量小于阳离子交换前值的5%，表明气体渗透率显著降低。相比之下，K或Cs交换前后ZSM-5膜的H₂O渗透通量值的降低幅度低于H₂，从而提高了H₂O/H₂分离性能。与NaZSM-5膜相比，K或Cs交换的ZSM-5膜表现出优异的H₂O渗透选择性，特别是在稀H₂O浓度（<1 vol%）下。
