(49d) Ozone Microbubble and Its Use in Arsenic Removal from Waste Water

Microbubble-based methods, in recent times, have been widely used for purification of water and wastewater. Microbubbles have several physicochemical properties, which make them eminently suitable for wastewater treatment. Many practical applications of ozone, oxygen and air microbubbles, some of which are currently at various stages of commercialization, have been presented in literature. In addition, directions for future research of microbubble technology and their potential applications have been identified. Treatment of waste water by ozonation is gaining importance due to its high oxidizing power. Arsenic is one the most toxic elements found in ground water. The ground water is majorly polluted with arsenic with its As(III) and As(V) sources. It is known that As(V) can be more easily removed from water by adsorptive methods than As(III). In this work, oxidation of more toxic As(III) to less toxic As(V) was studied in a pilot-plant by using ozone microbubbles. The microbubbles are widely acceptable in dissolving ozone in water. The role of ozone microbubble in the oxidation of As(III) under acidic conditions is enunciated and kinetics for the advance oxidation is evaluated based on the experimental results. Adsorption of As(V) on zirconium impregnated activated carbon (Zr‒AC) and amorphous zirconium oxide (Am-Zr) has been studied in this work. The adsorption of As(V) on both of these adsorbents was fast and effective. The As(V) adsorption capacity of Am-Zr was larger than that of Zr‒AC.