Advanced Oxidation Processes (AOP): The Power Beyond Biological Limits

Did you know that some pollutants cannot be removed by bacteria or traditional physical processes?

💊 Pharmaceutical residues, pesticides, hormones, dyes, surfactants, and even microplastics require a different kind of solution:

💥 AOP – Advanced Oxidation Processes

This is a powerful chemical technology based on the generation of hydroxyl radicals (•OH) — highly reactive molecules capable of breaking down complex organic compounds into CO₂ and H₂O.

🌪️ These radicals don’t just "mask" pollution. They destroy even the most resistant chemical bonds.

⚗️ How do AOPs work?

There are different combinations, all based on strong oxidizing agents:

COMBINATION MAIN MECHANISM

O₃ + H₂O₂ ozonolysis + •OH formation

UV + H₂O₂ photolysis + •OH formation

UV + TiO₂ (photocatalysis) semiconductor excitation + •OH

Fenton / Photo-Fenton Fe²⁺ ions + H₂O₂ (with or without UV light)

O₃ + UV direct and indirect oxidation combination

💡 The goal? To mineralize recalcitrant organic compounds and achieve purity levels unreachable by biological methods.

🧪 Where are AOPs applied?

🧴 Effluents from pharmaceutical and cosmetic industries 

🚩 Leachate from landfills 

👕 Effluents with persistent color (e.g., textile) 

💦 Final polishing for water reuse 

🦠 Toxicity reduction prior to final disposal

This article was authored by Éverton L. Petronilho