Study On The Hydrogenation Effect Of Catalyst On New Liquid Hydrogen Storage Material N-ethylcarbazole

As a new liquid hydrogen storage material, N-ethylcarbazole has a higher hydrogen storage capacity (5.8wt%) and can be dehydrogenated under lower temperature than traditional organic hydrides, making it promising candidate for hydrogen storage. However, catalysts still need to be optimized to achieve better catalytic hydrogenation performance for the application of N-ethylcarbazole.The present work firstly intrduced the research on the preparation of Ru catalyst and investigated the hydrogen performance of N-ethylcarbazole over Ru-Pt/Al2O3catalyst. The results reveal that the Ru/Al2O3catalyst reduced by hydrazine hydrate shows the best catalytic activity. The hydrogenation rate and capacity of N-ethylcarbazole catalyzed by Ru-Pt/Al2O3both increase with the rising temperature and reach the maximum at160℃. Almost all the N-ethylcarbazole was converted to N-perhydroethylcarbazole and N-octahydroethylcarbazole during the catalytic hydrogenation reaction.The hydrogenation reaction process of N-ethylcarbazole catalyzed by Ru/rGO was further studied and the effect of reaction temperature, pressure, the composition of ruthenium in Ru/rGO on the hydrogenation rate and absorption capacity was also discussed. Experiment results show that the prepared Ru/rGO has an excellent catalytic effect on the hydrogenation of N-ethylcarbazole. The hydrogenation property improved with the increasing amount of ruthenium in Ru/rGO, temperature and hydrogen pressure. The amount of absorbed hydrogen could achieve a considerable optimum (0.300mol) under the condition of160℃,6MPa and0.2g24.94wt%Ru/rGO when the amount of N-ethylcarbazole was10g.The kinetic analysis of N-ethylcarbazole catalyzed by Ru/rGO reveals that the initial hydrogenation is controlled by the chemical reaction over the catalyst’s surface. The apparent activation energy is estimated to be36.63kJ/mol, according to the following equation: Finally, the hydrogenation performance of N-ethylcarbazole over LaNis alloy was investigated and the hydrogen absorption reaction process was analyzed. The results revealed that the catalytic effect of fluorinated LaNis alloy was markedly improved compared with that of untreated one. Study on the morphology of fluorinated LaNis alloy showed that numerous fine microcrystals (100nm) were formed on the surface. The unique surface structure consisting of LaF3protective layer and Ni-rich sub-layer improved the catalytic activity of LaNis. Further investigation on the catalytic hydrogenation of N-ethylcarbazole over fluorinated LaNis alloy indicated that the hydrogen absorption performance was significantly affected by reaction temperature. In addition, increasing the hydrogen pressure could contribute to the hydrogenation of N-ethylcarbazole. The superior reaction condition was6.0MPa,443K,1.0g fluorinated LaNis,600rpm, and the corresponding hydrogen absorption capacity reached0.270mol.