Bio-based mono-aromatic hydrocarbons production from waste cooking oil pyrolysis using Ca5Mg5-C-N catalyst

Biomass, as the only renewable carbon source, plays a crucial role in restructuring the energy system and achieving carbon reduction goals. For this study, a Ca5Mg5-C-N catalyst was synthesized for mono-aromatic hydrocarbons production from waste cooking oil (WCO) pyrolysis, and the pathway was analyzed based on the distribution of model compounds pyrolysis products. Results showed that the Ca5Mg5-C-N catalyst exhibited a high SBET of 161.3883 m2/g. The catalyst contained acidic sites at 0.235 mmol/g and basic sites at 0.220 mmol/ g. The peak area of mono-aromatic hydrocarbons reached 3.225E8 during WCO pyrolysis with the Ca5Mg5-C-N, yielding about 2.72 times more than the non-catalyzed reaction. The basic sites of MgO and porous properties of carbon spheres in the Ca5Mg5-C-N catalyst promoted the cleavage of macromolecules, providing abundant precursors for aromatization. The strong basic sites and acidic sites of CaO and carbon spheres enhanced the reaction by offering more reactive sites for aromatization, significantly increasing aromatics generation. Additionally, the 5-6 & Aring; pore widths distribution enhanced the selectivity for mono-aromatic hydrocarbons. This study provides a catalytic pyrolysis pathway to produce mono-aromatic hydrocarbons from WCO, and offers insights into the targeted design of catalysts.