Application of microbubbles in chemistry, wastewater treatment, medicine, cosmetics, and agriculture: a review

Microbubbles are 10–100-μm bubbles with unique properties that find applications in chemical reactions, water aeration, sewage purification, biomedicine, skincare, and mineral flotation. Here, we review microbubbles with focus on basics, analysis, preparation, and applications. Microbubbles preparation can be done by lowering the pressure, by breaking the gas phase, or by electrochemistry. We present applications for improving gas–liquid reactions, wastewater treatment, mineral flotation, drug delivery, drinks, hyperoxia therapy, aquaculture, and agriculture. Industrial use of microbubbles is actually limited by the preparation of stable and uniformly sized microbubbles at large scale.