Thermal regeneration of spent granular activated carbon (GAC) using sintering, air-activation, and deoxygenation was investigated to determine the potential of this method for overcoming the drawbacks of thermal regeneration. The conditions for each step were optimized. The physicochemical properties of four regenerated GACs were assessed using BET, SEM, and FT-IR analysis. The suitability of the regenerated GACs for liquid-phase applications was assessed by phenol adsorption, using adsorption isotherms, kinetics, and thermodynamics. Sintering increased the micropore area and volume of regenerated GAC by 19% and 16%, respectively, and controlled excessive burn-off, reducing it by 19%. Air-activation has economic advantages because the reaction time is 80% less than that for steamactivation. Deoxygenation improved the maximum adsorption capacity by 7%, although the number of micropores was reduced. Regenerated GAC by sintering, air-activation, and deoxygenation was best for liquid-phase applications; the results show that these steps help to overcome the drawbacks of thermal regeneration.