Electrified dehydrogenation of methyl-cyclohexane: reactor modeling and process integration

Abstract

Liquid Organic Hydrogen Carriers (LOHC) have been proposed as hydrogen transport technology to overcome limitations related to its low volumetric density. However, the dehydrogenation step represents the technological bottleneck of the LOHC storage cycle. In this work, a process layout based on the adoption of an electrified packed foam reactor for the dehydrogenation of the LOHC pair Methyl-cyclohexane/Toluene (MCH/TOL) is reported for an intensified CO₂-free cycle. The effects on reactor performance of operating parameters such as Gas Hourly Space Velocity (GHSV), outlet pressure, and inlet temperature are studied. The proposed reactor reaches volumetric hydrogen productivity, expressed in terms of H₂ lower heating value of 3.18 $k{W}_{H_2-\text{LHV}}{L}_R^{-1}$ with 95 % of MCH conversion, improving the results of intensified reactor configurations reported in the literature. The reactor is then integrated into a process layout considering a large-scale hydrogen refueling station as a case study, and process-related KPIs are calculated. The designed dehydrogenation process provides 1000 kg day^-1 of hydrogen, with a purity of 99.8 %, and a specific consumption of 13.46 ${\text{kWh}\text{kg}}_{H_2}^{-1}$ This work represents the first application of an electrified packed-foam reactor to LOHC dehydrogenation and its integration in process simulation. It also potentially represents the starting point for future optimization studies to assess the competitiveness of this hydrogen transport technology.