Shaping of gallate-based metal-organic frameworks for adsorption separation of ethylene from acetylene and ethane

Shaping metal-organic frameworks (MOFs) powders into formed bodies plays a crucial role in opening up the excellent properties of MOFs to a broad range of applications. Gallate-based MOFs, termed as M-gallate (M = Co, Mg, Ni), have shown excellent performance for adsorption separation of C2 hydrocarbons. However, the industrial applications of MOF powders will inevitably confront problems of high pressure drop, pipe blockage, and dust pollution. Herein, we use hydroxypropyl cellulose (HPC) as a binder to produce gallate-based MOFs pellets. The crystal structure of the well-shaped materials after molding remained intact, and the surface area of the materials hardly decreases after shaping. Adsorption isotherms of C2 hydrocarbons including ethylene, ethane and acetylene on the activated powders and pellets of M-gallate were recorded and compared with the outperformers. The shaped pellets were also examined by breakthrough experiments on the fixed-bed separation of C2H2/C2H4 (1:99, v/v) and C2H4/C2H6 (50:50, v/v) gas mixtures. These results proved that M-gallate pellets was promising candidates for the practical industrial realization of C2 hydrocarbons separation.