Micro-Nano Bubbles Coupled with Ozone Catalyzed Oxidation for the Treatment of Organic Wastewater: A Review

Abstract

Micro-nano bubbles (MNBs) technology significantly enhances ozone dissolution, prolongs its residence time in aqueous solutions, and expands the contact area between ozone and organic pollutants, thereby improving ozone utilization efficiency. The collapse of MNBs generates hydroxyl radicals (·OH), which synergistically enhance the degradation of organic contaminants via catalytic ozonation. When combined with catalysts, ozone MNBs enable efficient pollutant mineralization across a wide pH range while minimizing ozone and catalyst consumption. This process is effective in a wide pH range, and the catalyst remains active after repeated use. This paper introduces the basic characteristics of micro-nano bubbles and ozone catalytic oxidation technology, focusing on the advantages and disadvantages of ozone micro-nano bubbles and catalytic ozonation in the degradation of organic wastewater, and summarizes the synergistic application of the two technologies in organic wastewater treatment. Meanwhile, the research progress of new catalysts, the energy consumption of micro-nano bubble generation equipment, and the future development of this technology in actual industrial operations are outlined.