A ZIF-8 membrane was prepared via counter diffusion method. To control the diffusion rate, two supports with different pore structure were employed, conventional and modified α-Al2O3 disc; disc A and disc B. The ZIF-8 membranes are derived their name from the supports; ZIF-8-A and ZIF-8-B. While ZIF-8-A was grown at the surface of the disc A, ZIF-8-B was grown inside the disc B. At 200 °C, ZIF-8-A and -B exhibited H2/CO2 separation factor (SF) of 6.69 and 8.21. In long-term thermal stability tests, both ZIF-8-A and -B were withstood their properties at 200 and 250 °C for 72 h. At 300 °C, SF of ZIF-8-A fell after ~2 h, however, that of ZIF-8-B dropped after ~10 h. To sum up these features, ZIF-8-B showed higher H2 selectivity and thermal stability than ZIF-8-A, since ZIF-8 membrane was synthesized inside of the support.

• Jungkyu Choi(Department of Chemical & Biological Engineering, Korea University)
• Eunhee Jang(Department of Chemical & Biological Engineering, Korea University)