A comprehensive evaluation of high-sulfur petroleum coke in CO2 gasification to produce low-carbon syngas

• Temperature has a greater effect on CO₂ gasification than the K₂CO₃ catalyst. • High K₂CO₃ loading (≥10 wt. %) inhibits gasification due to pore blockage. • Activation energy drops from 150 to 96.96 kJ/mol at 5 wt. % K₂CO₃. • CO₂ flowrate has minimal impact on gasification efficiency. • Optimal conditions: 900 °C, 5 wt. % K₂CO₃, 258 ml/min CO₂ for maximum conversion. This study investigates the potential of high-sulfur petroleum coke as a feedstock for CO 2 gasification to produce syngas, offering a novel pathway for CO 2 decarbonization and promote a circular economy in oil and gas industry. CO 2 gasification experiments were conducted under isothermal conditions using a thermogravimetric analyzer (TGA). K 2 CO 3 was employed as a catalyst at varying loadings from 0–20 wt.%. The kinetic models, Shrinking Core Model (SCM) and Volume Reaction Model (VRM) were applied to describe the gasification reaction rate and the activation energy. Catalytic enhancement significantly improved the reactivity and lowering activation energy from 150.66 kJ/mol to 96.96 kJ/mol at a 5 wt.% catalyst loading. Multi objective optimization via Response Surface Methodology (RSM) demonstrated high R² values > 93 % for petroleum coke conversion, CO yield and CO 2 composition. Under optimized conditions 62 % petroleum coke conversion and 42 mol% CO yield were achieved. The novelty of this work lies in its integrated approach to petroleum coke- CO 2 gasification by combining study on catalytic enhancement, kinetic modeling and statistical optimization. This contributes to the economic viability of a decarbonization pathway aligned with circular economic principles.