Enhancing processability and dormancy time of liquid hydrogen storage via MOF Pelletization

Abstract

The efficient storage and transportation of hydrogen are critical challenges in advancing hydrogen as a sustainable energy carrier. This study investigates the potential of metal-organic frameworks (MOFs), specifically Ni-MOF-74 and ZIF-8 pellets, in enhancing hydrogen storage systems. By pelletizing MOF materials, this research achieves practical improvements in volumetric uptake compared to liquid hydrogen (LH2) systems, with MOF pellets demonstrating up to 49.70% of the storage capacity of LH2 tank vessels. Pelletization not only increases processability but also maintains structural stability, achieving 90% or more of the adsorption capacity of powdered MOFs. Additionally, the incorporation of MOFs significantly prolongs the dormancy period of LH2 by leveraging the heat of adsorption, a property that replaces the hydrogen‑hydrogen interactions in LH2 with stronger hydrogen-surface interactions. The Ni-MOF-74 pellet exhibits an average heat of adsorption of 6.56 kJ/ mol, resulting in a dormancy period 5 times that of LH2 tanks. These results highlight the dual benefits of increased volumetric efficiency and extended hydrogen dormancy, offering a robust and practical solution for long-term hydrogen storage and transportation.