Filtrates with Hydroxyl Radicals Prepared using Al + Acid + H₂O₂ for Removing Organic Pollutants

Abstract

In this work, for the first time, high-activity filtrates were prepared by the reaction of aluminum (Al) powder with hydrogen peroxide (H 2 O 2 ) in acidic solution and then filtration, which were used to degrade various organic pollutants such as phenol, methyl orange, and bisphenol A. It was found that the filtrates can effectively degrade and mineralize various organic pollutants and have a high efficiency comparable to their parent Al + acid + H 2 O 2 suspensions. The filtrates can keep their high activity for several weeks under ambient conditions, and the activity depends on their initial pH value. At a pH value of ∼3.5, the reaction activity of filtrates is the best. Electron spin resonance spectroscopy (ESR) analyses indicated that there is a large quantity of stable hydroxyl radicals (OH • ) existing in the filtrates, which are responsible for the removal of organic pollutants. Furthermore, the related factors are discussed.

High Recovery of Ceramic Membrane Cleaning Remediation by Ozone Nanobubble Technology

“…The collapse of NBs results in the generation of highly localized pressures and temperatures, known as cavitation . The high temperatures and pressures experienced during collapse lead to the formation of ROS specifically hydroxyl radicals ( • OH). − Due to their high reactivity, hydroxyl radicals rapidly react with a broad range of organic contaminants, including pollutants, pathogens, and dyes. ,, …”

“… 55 − 57 Due to their high reactivity, hydroxyl radicals rapidly react with a broad range of organic contaminants, including pollutants, pathogens, and dyes. 17 , 58 , 59 …”

“…55−57 Due to their high reactivity, hydroxyl radicals rapidly react with a broad range of organic contaminants, including pollutants, pathogens, and dyes. 17,58,59 Figure 7a,b represents the size and zeta potential of NBs upon 4 h processing, respectively. The peak distribution value, representing 100% of the ozone-NB, is found to be ∼213.2 nm in size.…”