Ozone (O₃) generates hydroxyl radicals (·OH) under the synergistic effects of hydrogen peroxide (H₂O₂) and UV catalysis. These radicals break down and degrade difficult-to-degrade organic compounds until they are completely mineralized into carbon dioxide and water. The process offers flexible options: O₃/H₂O₂, UV/H₂O₂, O₃/UV, and O₃/H₂O₂/UV.