An Effective Strategy Towards Obtaining Reliable Breakthrough Curves of Solid Adsorbents.

Abstract

Metal-organic frameworks (MOFs) have demonstrated their versatility in a wide range of applications, including chemical separation and gas capture and storage. In industrial adsorption processes, MOFs are integral to creating selective gas adsorption fixed beds. In this context, the assessment of their separation performance under relevant conditions often relies on breakthrough experiments. One aspect frequently overlooked in these experiments is the shaping of MOF powders, which can significantly impact the accuracy of breakthrough results. In this study, we present an approach for immobilizing MOF particles on the surface of glass beads (GBs) utilizing trimethylolpropane triglycidyl ether (TMPTGE) as a binder, leading to the creation of MOF@GB materials. We successfully synthesized five targeted MOF composites, namely SIFSIX-3-Ni@GB, CALF-20@GB, UiO-66@GB, HKUST-1@GB, and MOF-808@GB, each possessing distinct pore sizes and structural topologies. Characterization studies employing powder X-ray diffraction (PXRD) and adsorption isotherm analyses demonstrated that MOFs@GB retained their crystallinity and 73–90% of the BET area of their parent MOFs. Dynamic breakthrough experiments revealed that, in comparison to their parent MOFs, MOF@GB configurations enhanced the accuracy of breakthrough measurements by mitigating pressure build-up and minimizing reductions in gas flow rate. This work underscores the significance of meticulous experimental design, specifically in shaping MOF powders, to optimize the efficacy of breakthrough experiments. Our proposed strategy aims to provide a versatile platform for MOF powder processing, thereby facilitating more reliable breakthrough experiments.