Green Hydrogen Storage in LOHCs via Catalytic Hydrogenation: In-depth Compound Analysis and Kinetic Study of Commercial Dibenzyltoluene Mixture

International audience ; The storage and transport of green hydrogen is one of the major challenges in hydrogen processes. Hydrogen produced with renewable energy can be efficiently stored in LOHCs (Liquid Organic Hydrogen Carriers) through a catalytic hydrogenation of the LOHC compounds, and the release of hydrogen is typically reached via the dehydrogenation of their H 2-rich form. The mixture of dibenzyltoluene (H0-DBT) isomers could be valued for its high storage capacity (6.2 wt-%) and large liquid phase temperature range (-34 ~ 386 °C). H0-DBT hydrogenation was found to be a 3-stepconsecutive reaction with side-side-middle (SSM) preference, producing H6-DBT and H12-DBT as intermediates. However, a deeper understanding of isomers in the mixture and their kinetics of H2 storage were not present in the literature, which are crucial for reactor and process design. In this study, the identification of Hx-DBT isomers was achieved with the help of GC/MS and targeted organic synthesis coupled with kinetic modelling. Kinetic studies have been carried out using commercial Pt/Al2O3 and Pt/C catalysts under different conditions including temperature, pressure and catalyst particle size etc. Kinetic models taking into consideration mass transfer limitations, aromatic ring adsorption, catalyst deactivation and poisoning have been established for each Hx-DBT family and most Hx-DBT isomers.