Fast hydrogenation kinetics of acridine as a candidate of liquid organic hydrogen carrier family with high capacity

Synthesis of bifunctional Ru–Pd catalysts following a double reduction method: hydrogenation/dehydrogenation of liquid organic hydrogen carriers

“…Cheng and co-workers have primarily focused on studying aromatic heterocyclic LOHCs, such as N -ethylcarbazole (NECZ, 5.79 wt%), 31,32 N -propylcarbazole (NPCZ, 5.43 wt%), 33 N -ethylindole (NEID,5.23 wt%), 34,35 2-methylindole (2-MID, 5.76 wt%), 36 7-ethylindole (7-EID,5.23 wt%), 37 1-methylindole (1-MID, 5.76 wt%), 38 and acridine (ACD,7.25 wt%). 39 Izquierdo et al 40 investigated a series of compounds based on N- and S-heterocycles through density functional theory, and their results indicated that 1 H -pyrrole/tetrahydro-1 H -pyrrole and thiophene/tetrahydrothiophene can be used as candidate materials for LOHCs. The thermophysical properties (heat capacity, density, viscosity, surface tension, and refractive index) of carbazole and N -ethylcarbazole as well as those of their hydrogenated derivatives were studied by Stark et al 41 This series of heterocyclic compounds meet the minimum weight density (5.5 wt%) and volumetric hydrogen storage density (40 kg h 2 m −3 ) proposed by the US Department of Energy.…”

Study of catalytic hydrogenation and dehydrogenation of 2,3-dimethylindole for hydrogen storage application

“…LOHCs (liquid organic hydrogen carriers) have been considered as promising hydrogen storage substrates in recent years. [21][22][23][24][25][26] Hydrogen was bonded to these compounds through catalytic hydrogenation and released through catalytic dehydrogenation. As early as 1970s, aromatic hydrocarbon compounds were initially proposed as hydrogen storage carriers such as benzene and toluene, which were mainly applied in industrial process (e.g., in oil reneries).…”

Ultralow Rh Bimetallic Catalysts with High Catalytic Activity for the Hydrogenation of N-Ethylcarbazole

“…As an energy carrier, hydrogen has been developed in a variety of storage methods over the past few decades, for example, metal hydrides, complex hydrides, chemical hydrides, and sorbents. ,, The alternative method for storing and transporting hydrogen under environmental conditions is the use of liquid organic hydrogen carriers (LOHC). , LOHCs are green, safe, reliable, controllable, and easy to manage, and finally they can be achieved in industrial applications, which show great social and economic benefits. , Furthermore, they meet the long-term energy storage need, will not cause energy loss due to evaporation or other things, and can be transported in a simplistic manner. , Since Sultan first proposed the traditional concept of LOHC in the 1970s, dozens of aromatic compounds have been reported as hydrogen carriers for hydrogen storage, and each hydrogen carrier has a corresponding theoretical hydrogen storage density, the calculation of theoretical hydrogen storage being based on the compounds that can uptake a maximum equivalent of hydrogen to generate fully hydrogenated product, which accounts for the mass of the final hydrogenation product. These are benzene (7.14 wt %), toluene (6.18 wt %), , and naphthalene (7.3 wt %). , The hydrogenation process is accomplished by the carbon double bonds in hydrogenation. , However, the dehydrogenation temperature reaches above 300 °C, which is too high to work properly for a fuel cell. The American Air Chemical Company investigated several polycyclic aromatic compounds and their conjugated molecules in their patents .…”

“…17,18 The hydrogenation process is accomplished by the carbon double bonds in hydrogenation. 19,20 However, the dehydrogenation temperature reaches above 300 °C, 21 polycyclic aromatic compounds and their conjugated molecules in their patents. 22 Through thermodynamic calculations, it was found that the polycyclic aromatic derivatives formed by substituting a C atom with an N atom have smaller enthalpies of dehydrogenation, which means a lower temperature in dehydrogenation.…”