Modisha, PhillimonGaridzirai, RudaviroOuma, Cecil N.M.Bessarabov, DmitriGqogqa, Pumeza2019-10-182019-10-182019Modisha, P. et al. 2019. Evaluation of catalyst activity for release of hydrogen from liquid organic hydrogen carriers. International journal of hydrogen energy, 44(39): 21926-21935. [https://doi.org/10.1016/j.ijhydene.2019.06.212]0360-3199http://hdl.handle.net/10394/33439https://www.sciencedirect.com/science/article/pii/S0360319919325182https://doi.org/10.1016/j.ijhydene.2019.06.212This contribution investigate the effect of parameters for production of hydrogen by catalytic dehydrogenation of perhydrodibenzyltoluene (H18-DBT). The sensitivity of the dehydrogenation reaction to temperature (290–320 °C) is justified by an increase in degree of dehydrogenation (DoD) from 40 to 90% when using 1 wt % Pt/Al2O3 catalyst. However, the increase in temperature increases the hydrogen production rate and decreases the hydrogen purity by increasing the formation of by-products. In addition, the DoD of 96% is obtained when 2 wt % Pt/Al2O3 is used at 320 °C. The DoD obtained for Pd, Pt, and Pt–Pd catalysts is 11, 82 and 6%, respectively. Therefore, Pd is not a metal of choice for dehydrogenation of H18-DBT, in both monometallic and bimetallic system. The ab-initio density functional theory (DFT) calculations are consistent with this observation. Furthermore, dehydrogenation of H18-DBT followed 1st order reaction kinetics and the activation energies for 1 wt % Pt/Al2O3, 1 wt % Pd/Al2O3 and 1:1 wt % Pt–Pd/Al2O3 catalysts are: 205, 84 and 66 kJ/mol, respectivelyenDegree of dehydrogenationMetal dispersionReduction temperatureFirst-order reaction kineticsDensity functional theoryHydrogen purityArticle