Ethylene is widely used in the petrochemical industry. During the production of ethylene, acetylene is generated as a byproduct. This byproduct can poison catalysts and cause, for example, the termination of the polymerization of C2H4. Therefore, the removal of acetylene from ethylene is important. Research into porous materials for C2H2/C2H4 separation has been focused on metal-organic frameworks (MOFs). The use of porous organic frameworks (POFs) for this gas separation is still rare.
Hao Ren, Jia Liu, Jilin University, Changchun, China, and colleagues have synthesized a stable 2D crystalline polyimide porous organic framework called PAF-120. The POF was synthesized by an imidization of the linear naphthalene-1,4,5,8-tetracarboxylic dianhydride and the triangular 1,3,5-tris(4-aminophenyl) benzene. PAF-120 is thermally and chemically stable.
The researchers found that PAF-120 can achieve a good, selective separation of C2H2 from C2H4. PAF-120 also effectively separates CO2 and N2. At 298 K and 1 bar, the C2H2/C2H4 and CO2/N2 selectivities were calculated to be 4.1 and 68.7, respectively. The framework has the highest selectivity for C2H2/C2H4 separation among POFs under these conditions.
- Construction of a Stable Crystalline Polyimide Porous Organic Framework for C2H2/C2H4 and CO2/N2 Separation,
Lingchang Jiang, Pengyuan Wang, Meiping Li, Panpan Zhang, Jialu Li, Jia Liu, Yanhang Ma, Hao Ren, Guangshan Zhu,
Chem. Eur. J. 2019.