Water pollution is one of the problems that industrial regions face. It can be solved by purifying wastewater from plants and factories before it reaches water bodies used by the public. Modern means of treatment are effective but expensive or inconvenient to use. However, scientists of South Ural State University (SUSU) have developed a new method of obtaining material for wastewater treatment that supersedes the existing analogues. A patent has already been obtained for development.
All industrial enterprises, regardless of their activities, pollute water ecosystems with sewage. Wastewater contains persistent organic compounds—poisonous substances that have a negative impact on human health and the environment. Such compounds should be removed from water to prevent their spread.
Currently, there are two methods of treating wastewater for organic compounds that are actively used: adsorption and reagent oxidation. However, these are considered expensive; it is much cheaper and more profitable to use reagent-free photocatalytic water treatment.
South Ural State University has been working on the development of photocatalysts for several years now. The research is conducted under the supervision of Vyacheslav Avdin, Dean of the Faculty of Chemistry of the Institute of Natural Sciences and Mathematics (INSM). Our scientists work with photocatalysts based on transition metals. The samples are nanopowders. They are highly efficient, but the disadvantage of these catalysts is that nanoparticles are difficult to extract from the water after the purification process.
A new study conducted by SUSU scientists has allowed them to obtain a photocatalyst with a thermostable microporous coating based on a mixed titanium-silicon oxide. The macroform is easy to use, and the substance is as active as nanoparticles. The patent certificate No. 2733936 has been obtained for the innovative method of producing the photocatalyst.
“Our method is innovative because it allows us to obtain mechanically durable thermostable microporous coatings based on anatase with the help of relatively inexpensive and low-toxic reagents through a relatively simple procedure. The coatings exhibit rather high photocatalytic activity with respect to persistent organic pollutants (such as phenolic compounds) even at low UV irradiation power,” explained Aleksandr Gorshkov, the author of the patent and postgraduate student of the Department of Ecology and Chemical Engineering of the SUSU INSM.
The method of obtaining a thermostable coating with photocatalytic properties suggested by Aleksandr Gorshkov helps prevent the reducing in the activity of the substance even when it is heated up to 700 degrees Celsius because anatase nanocrystals are stabilized in the silicate matrix. The microporosity of the substance also increases the activity of the catalyst, because this property affects the high specific surface area.
When the laboratory tests are completed, the researchers want to test the patented coating on actual wastewater samples. The next step is to design, build, and test a pilot water treatment plant.