Dehydro-aromatization of renewable bio-naphtha over Pd/γ-Al2O3 catalyst

• 0.5 wt% monometallic Pd/ γ -Al 2 O 3 reduced catalyst used for dehydro-aromatization of renewable bio-naphtha. • High selectivity towards iso -paraffins and alkyl-aromatics. • Free energy and heat of reaction were evaluated using DFT calculations. • The reaction and coking kinetics were evaluated for the calculation of activation energy. An effort has been made to eliminate the problem of chlorine loss and equipment corrosion caused by the conventional chlorinated alumina-based reforming noble metal catalyst. The manuscript has reported the gas phase aromatization of renewable bio-naphtha in the molecular hydrogen and monometallic Pd/γ-Al 2 O 3 catalyst. In addition, First-principle density functional theory calculations were considered to calculate the free energy and heat of reaction for the conversion of renewable bio-naphtha into toluene on the surface of Pd/γ-Al 2 O 3 . The catalyst was characterized by XRD, SEM, TEM, BET, NH 3 -TPD, TGA/DTA, XPS, and FTIR. All the experiments were carried out in a stirred batch reactor at various reaction conditions for the dehydroaromatization of bio-naphtha. The maximum selectivity towards aromatics of 72.3% was achieved at the optimal reaction conditions of temperature = 375 °C, P H2 = 5 bar, catalyst mass = 0.6, and the reaction time = 14 h. The reaction and coking kinetics were applied to calculate the activation energy of 78.02 kJ/mol and 16.17 kJ/mol, respectively. The catalyst activity was reported in terms of turnover frequency (TOF), i.e., 90.2 h −1 . A plausible mechanism for bio-naphtha aromatization via catalytic dehydrogenation route with the active species Pd (0)/Pd (II) is also elucidated.