| 초록 |
Zeolitic imidazolate frameworks (ZIFs) have potential use in practical separations due to a flexible control over pore sizes, along with chemical and thermal stabilities. We first explored the effect of thermal treatments on the ZIF-7 structure, known for its promising characteristics toward H2 separations (pore size of ~0.29 nm vs. kinetic diameter of H2: 0.289 nm). In addition, the thermal stability of ZIF-8s, which are also known as molecular sieves (pore size; 0.34 nm) for H2 separations, has been investigated under various heat-treatment conditions. The detailed procedure to ensure proper thermal activation will be addressed and further correlated with their intrinsic adsorption properties. Finally, ZIF-8 has been adopted to constitute continuous membranes. The resulting membranes were used to evaluate their H2 perm-selectivities in an effort to check their compatibility in the membrane reactor configuration. The separation performance in favor of H2 permeation rates through ZIF-8 membranes will be mainly discussed, while considering their reliable applications equipped with the long-term stability. |
