Valuable Biofuel Production Via Pyrolysis Process of Olive Pomace Over Alkali and Transition Metal Oxides Catalysts Supported on Activated Biochar

In this research, non-catalytic and catalytic pyrolysis of olive pomace as a second generation of biomass has been investigated for the production of valuable biofuels. Feasibility assessment and determination of optimum operating condition of catalytic pyrolysis such as catalyst loading and temperature is the main goal of this study. Bio-oil from the pyrolysis of olive pomace has high amounts of oxygenated compounds, so in this study, NiO, CoO, MgO and CaO catalyst supported on activated biochar are used to upgrade the bio-oil via deoxygenation process. The achieved results indicated that the maximum bio-oil production yield through non-catalytic process is 56 wt. % at temperature of 500°C, which mainly includes oxygenated compounds with more than 90 wt. % content. The results indicate that catalytic pyrolysis process of olive pomace over alkali metal oxides catalysts provides products such as hydrocarbons, ketones and aldehydes, which confirms occurrence of decarboxylation, decarbonylation, ketonization and aldol condensation reactions. MgO/biochar and CaO/biochar catalysts represent similar performance in the conversion of fatty acids, but CaO/biochar deoxygenation performance is better than MgO/biochar catalyst. Catalytic pyrolysis investigations indicate that transition metal oxides (NiO and Co3O4/biochar) catalysts represent higher deoxugenation activity than alkali metal oxides catalyst. This research provides novel active catalysts for catalytic pyrolysis of biomass, which also enables to upgrade the derived pyrolysis oil to biofuel via direct deoxygenation process