An enhanced palm oil pyrolysis to bio-oil using dolomite-derived ZnO/CaO composite

This study investigates the synthesis and catalytic activity of a ZnO/CaO composite derived from dolomite for the pyrolysis of palm oil. The composite was prepared via wet impregnation of dolomite with zinc chloride followed by high-temperature calcination. Based on the result, it is revealed that wet-impregnation and calcination of dolomite yield the expected ZnO/CaO composite with high crystallinity and purity. Results also indicate that the composite exhibits enhanced catalytic activity and stability in producing bio-oil compared to CaO despite yielding less in the first cycle. Moreover, the composite demonstrates a shift in production from kerosine (C12-C18) and heavy oil (C19-C21) to gasoline (C5-C11) fractions over reaction cycles, while CaO exhibits the opposite trend. This phenomenon is attributed to the synergistic activity between ZnO and CaO, which enhances the catalyst’s resistance to deactivation from coke deposition. Further analysis reveals that decarboxylation, β-scissions, and bond cleavages are major reactions responsible for transforming palm oil into its derivative products. Such enhancement in the production of lighter gasoline fractions signifies the catalyst’s potential for producing bio-oil that could substitute conventional fossil-based fuels.