• Optimal reduction efficiency achieved at C/O molar ratio of 1.2, reaching ~90% reaction fraction.
• Addition of CaF2 lowers melting point and viscosity, enhancing reduction rate.
• Reduction rate increases with temperature, controlled by gas-phase diffusion.
• Two-stage kinetics with activation energies of 56.10 and 100.52 kJ/mol, providing predictive equations.