Chemistry | 2019
Adsorptive separation of acetylene from ethylene in isostructural gallate-based metal-organic frameworks.
Abstract
The separation of acetylene from ethylene is of paramount importance in the purification of chemical feedstocks for industrial manufacturing. Herein, we report an isostructural series of gallate-based MOFs, M-gallate (M= Ni, Mg, Co), featuring three-dimensionally interconnected zigzag channels, whose aperture size can be finely tuned within 0.3 Å via metal replacement. Controlling the aperture size of M-gallate materials slightly from 3.69 down to 3.47 Å could result in a dramatic enhancement of C 2 H 2 /C 2 H 4 separation performance. As the smallest radius among the studied metal ions, Ni-gallate exhibits the best C 2 H 2 /C 2 H 4 adsorption separation performance due to the strongest confinement effect, ranking after the state-of-the-art UTSA-200a with a C 2 H 4 productivity of 85.6 mol/L from 1/99 C 2 H 2 /C 2 H 4 mixture. The isostructural gallate-based MOFs, readily synthesized from inexpensive gallic acid, are demonstrated to be a new top-performing porous material for highly efficient adsorption C 2 H 2 from C 2 H 4 .