Wang, T.; Yang, C.; Sun, P.; Wang, M.; Lin, F.; Fiallos, M.; Khu, S.-T. Generation Mechanism of Hydroxyl Free Radicals in Micro–Nanobubbles Water and Its Prospect in Drinking Water. Processes2024, 12, 683.
Wang, T.; Yang, C.; Sun, P.; Wang, M.; Lin, F.; Fiallos, M.; Khu, S.-T. Generation Mechanism of Hydroxyl Free Radicals in Micro–Nanobubbles Water and Its Prospect in Drinking Water. Processes 2024, 12, 683.
Wang, T.; Yang, C.; Sun, P.; Wang, M.; Lin, F.; Fiallos, M.; Khu, S.-T. Generation Mechanism of Hydroxyl Free Radicals in Micro–Nanobubbles Water and Its Prospect in Drinking Water. Processes2024, 12, 683.
Wang, T.; Yang, C.; Sun, P.; Wang, M.; Lin, F.; Fiallos, M.; Khu, S.-T. Generation Mechanism of Hydroxyl Free Radicals in Micro–Nanobubbles Water and Its Prospect in Drinking Water. Processes 2024, 12, 683.
Abstract
Micro nano bubbles (MNBs) can generate ·OH in situ, which provides a new idea for the safe and efficient removal of pollutants in water supply systems. However, the difficulty in obtaining stable MNBs causes the low efficiency of ·OH generation, which makes the inability to guarantee the removal efficiency of pollutants. This paper reviews the application research of MNBs technology in water security from three aspects: the generation process of MNBs in water, the generation rule of ·OH during MNBs collapse, and the control mechanism of MNBs on pollutants and biofilms. We found that MNBs generation methods are divided into chemical and mechanical (about 10 kinds) categories, and the instability of bubble size restricts the application of MNBs technology. The generation of ·OH by MNBs is affected by pH, gas source, bubble size, temperature, external stimulation. And pH and external stimulus have more influence on ·OH generation in situ than other factors. Adjusting pH to alkaline or acidic conditions and selecting ozone or oxygen as the gas source can promote the ·OH generation. MNBs’ collapse also releases a large amount of energy, which the temperature and pressure can reach 3000K and 5Gpa respectively, making it efficient to remove ≈90 % of pollutants (i.e., trichloroethylene, benzene, and chlorobenzene). The biofilm can also be removed by physical, chemical, and thermal effect. MNBs technology also has great application potential in drinking water, which can be applied to improve water quality, optimize household water purifiers, and enhance the taste of bottled water. Under the premise of safety, let people of different ages taste, finding that compared with ordinary drinking water, 85.7 % of people think MNBs water is softer, 73.3 % of people think MNBs water is sweeter. This further proves that MNBs water has a great prospect in the drinking water application. This review provides innovative theoretical support for solving the problem of drinking water safety.
Environmental and Earth Sciences, Water Science and Technology
Copyright:
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