How Do Ozone Decomposition Catalysts Degrade COD Levels in Wastewater?

In industrial wastewater treatment, COD (Chemical Oxygen Demand) is a core indicator for measuring the degree of water pollution, and its efficient degradation is key to achieving environmental standards. Ozone decomposition catalysts, as a core component of high-efficiency COD treatment technology, are becoming the preferred solution for industries such as chemical engineering and dyeing.

COD mainly originates from three major areas: industrial wastewater accounts for over 60%, such as benzene and phenolic wastewater from chemical industrial parks, and dye residue wastewater from the dyeing industry; domestic sewage contains large amounts of carbohydrates, proteins, and other organic matter; and agricultural non-point source pollution comes from pesticide residues and livestock and poultry breeding wastewater. Among these, industrial wastewater, due to its complex composition and poor biodegradability (BOD/COD often below 0.2), poses a significant treatment challenge.

Traditional biochemical methods have limited effectiveness against recalcitrant organic matter, while ozone catalytic oxidation technology has achieved a breakthrough. The core function of ozone decomposition catalysts is to accelerate the conversion of ozone into hydroxyl radicals (·OH). Direct ozone oxidation has limited oxidizing power (redox potential 2.07V) and high selectivity; however, catalysts induce electron transfer through the active sites of transition metals (Mn, Fe, etc.), enabling ozone to efficiently generate ·OH, with a redox potential reaching 2.8V, which can indiscriminately mineralize organic matter.

In practical applications, after a chemical industrial park adopted a manganese-based ozone decomposition catalyst, the COD of its wastewater decreased from 300 mg/L to below 100 mg/L, achieving a removal rate of 67%. The BOD/COD ratio increased from 0.15 to over 0.3, creating conditions for subsequent biological treatment. Another dyeing and printing plant used a manganese-based activated carbon catalyst to treat its effluent. Under conditions of 25℃ and a catalyst dosage of 10g, the COD decreased from 96 mg/L to 32.5 mg/L within 20 minutes, achieving a removal rate of 66.1%.

These cases demonstrate the advantages of ozone decomposition catalysts: through a synergistic process of adsorption-catalysis-oxidation, they improve ozone utilization by over 80% while extending catalyst lifespan to approximately 6 years. For treating highly challenging wastewater, it has become a core technological support for achieving COD compliance.

Author: Hazel 

Date: 2025-11-18