Hydrogenation of dibenzyltoluene and the catalytic performance of Pt/Al2O3 with various Pt loadings for hydrogen production from perhydro‐dibenzyltoluene.

Summary: The characteristics of the hydrogenation of dibenzyltoluene and dehydrogenation of perhydro‐dibenzyltoluene (H18‐DBT) are investigated. The hydrogenation experiments are conducted using Raney‐Ni. It is found that 170°C and 7 MPa is the optimal reaction condition at which the hydrogen capacity of 6.2 wt% is achieved in 30 hours. The optimal temperature for the dehydrogenation of H18‐DBT is found to be 290°C. Moreover, the dehydrogenation of H18‐DBT is carried out over Pt/Al2O3 catalysts with different Pt metal loadings (1% ~ 5%). The results elucidate that 5% Pt/Al2O3 is the most active catalyst yielding 90.2% of the stored hydrogen in 7 hours. The catalytic activity of the catalysts is in the order 5% > 4% > 3% > 2% > 1% Pt/Al2O3. The increment in catalyst dosage increases the reaction rate and hydrogen yield%. Lastly, the cyclic experiments are conducted and DBT is found to be quite stable in all three cycles. HIGHLIGHTS: The complete hydrogenation (6.2 wt%) of dibenzyltoluene is achieved at 170°C and 5 ~ 7 MPa.The dehydrogenation of perhydro‐dibenzyltoluene is conducted over 1 ~ 5% Pt/Al2O3.The 90.2% of stored hydrogen is produced over the optimal catalyst, 5% Pt/Al2O3.The hydrogen production in all the three cycles is almost similar which makes dibenzyltoluene a stable liquid organic hydrogen carrier. [ABSTRACT FROM AUTHOR]