Regeneration strategies for metal–organic frameworks post acidic gas capture

Abstract

Metal-organic frameworks (MOFs) are highly porous inorganic–organic hybrid materials with exceptional uptake capacity for various targets such as deleterious acidic gases (e.g., hydrogen sulfide (H2S), sulfur dioxide (SO2), and nitrogen dioxide (NO2)). Despite the significance of such purification processes, relatively little is known about the strategies required for the regeneration of MOFs post acidic gas capture. To help gain a better knowledge on the regenerability of MOFs with high gas uptake, a comprehensive review is offered to describe various types of MOF regeneration methods applied after capturing of H2S, SO2, and NO2. Pressure- and temperature-swing methods can be used to reactivate MOFs upon physical adsorption of gases. Although there are more difficulties in regenerating MOFs with chemisorbed sulfurous gases, some reactivation strategies (e.g., solvent and ultraviolet irradiation-based treatments) can be recommended to facilitate their regeneration. Overall, the regenerability of MOF is highlighted to help expand their utility in air quality remediation.