A new photocatalyst for water purification from phenol, one of the most common and toxic pollutants, was proposed by NUST MISIS scientists together with colleagues from China . When exposed to ultraviolet light, the material oxidizes phenol to carbon dioxide, which is harmless to humans. This was reported to Gazeta.Ru at the university.
The source of phenol is usually the effluents of oil refining, wood chemical, aniline and other industries. Phenol is not only toxic, but also absorbs oxygen dissolved in water, which adversely affects the life of water bodies. One of the ways to combat pollution is by reactions in which toxic substances are destroyed by light in the presence of special substances – photocatalysts.
NUST MISIS specialists, together with colleagues from Fudan University in China, proposed using hexagonal boron nitride (h-BN) powder as a photocatalyst, a two-dimensional material with relatively high chemical stability and a large surface area. Since the chemical reaction in water treatment occurs at the interface between the surface of the catalyst and the aqueous solution, the larger the surface area, the more efficient the process will be.
“Due to simple equipment – a UV lamp and a magnetic stirrer – and the absence of the need for additional reactive oxidizing agents, the excess of which can adversely affect the environment, photocatalytic oxidation of organic matter is very promising for water purification from phenol. The effectiveness of the technology is closely related to the development of materials – photocatalysts, thanks to which all the “magic” happens. These substances are added to contaminated water. When exposed to light, electrons are excited, the energy of which becomes sufficient for their participation in various chemical processes. When our material is exposed to ultraviolet light, substances are formed in water that oxidize phenol to carbon dioxide and water,” he told Gazeta.ru.
In their work, the scientists used ultraviolet as a source of excitation of electrons. In the future, the researchers plan to change the structure of the photocatalyst so that visible light can be used.