Use of breakthrough experiment to evaluate the performance of hydrogen isotope separation for metal-organic frameworks M-MOF-74 (M=Co, Ni, Mg, Zn)

Abstract

The unique adsorption performance of metal-organic frameworks (MOFs) indicates a new direction for gas separation and purification. The low-temperature distillation, as a traditional technique for hydrogen isotope separation, is limited as it is a high energy- and cost-intensive process. Instead of utilizing such a conventional separation route, we use ordered microporous frameworks based on a physical adsorption mechanism to solve the challenge of hydrogen isotope separation. Herein we analyze M-MOF-74 (M=Co, Ni, Mg, Zn), featuring a hexagonal channel about 11 A and high density of open metal sites, for their ability to separate and purify deuterium from the hydrogen isotope mixture by dynamic column breakthrough experiments. Our results show that the combination of the strength of binding sites, density of coordinatively unsaturated metal sites and hydrogen isotope adsorption capacity of materials renders Co-MOF-74 as an optimal adsorbent for the capture of deuterium from hydrogen isotope mixtures in a simulated industrial process.