Scientists from South Ural State University have developed electrochemical methods for detecting organic and inorganic substances in water. This applies to any water bodies: potable water reservoirs, industrial wastewater, and treatment facilities.
"That is, everything related to water: clean and dirty, before and after the outlet," comments Roman Morozov, a Research Fellow at the Laboratory of Environmental Problems of Post-Industrial Agglomeration. "Currently, the chromatographic method is used to detect organic and inorganic substances in a solution. It has several disadvantages: expensive equipment, complex process of training personnel, and long process of sampling. In addition, it cannot be made portable, that is, a specialist goes to the site, takes a water sample and takes it to a stationary laboratory. We offer a fundamentally different approach."
The Chelyabinsk scientists have developed an express method: a specialist on site plunges an electrode in water, receives a signal and immediately calculates the concentration of dissolved substances. A small device, a potentiostat, is used in the work. The essence of the invention is that SUSU scientists have selected components aimed at detecting specific substances in a solution, for example, trichlorophenol and nitrophenol – some of the most common industrial pollutants.
"Russia produces a huge amount of phenol and its derivatives," says Roman Morozov. "They are used in the production of various plastics, dyes, pesticides – almost all products of the chemical industry are somehow related to phenol. And this is a harmful substance that, when released into the environment, continues to react and form new, more toxic compounds. For example, it forms chlorophenol in chlorinated water."
The SUSU chemists are also selecting reagents capable of detecting drugs and antibiotics in water. Currently, they are studying the widely used amoxicillin, which is used to treat humans and animals. First, scientists select a composite material that reacts with the antibiotic, “implant” it into the electrode, and optimize the signal frequency, amplitude, and range. As a result, the device shows the desired pollutant even in minimal concentrations.
It takes three to six months to select indicators for each pollutant. The research is being conducted in three laboratories by a team of 10 people led by Professor Viacheslav Avdin and Serbian scientist Dalibor Stankovich. The chemists are currently focusing their efforts on the methods for identifying specific classes of pollutants.
"First of all, these are halogen-aromatic compounds, because they decompose poorly in the environment," says Roman Morozov. "They are called micropollutants, and treatment facilities cannot cope with them because they are present in low concentrations in water, but they can accumulate in the body or in nature and cause harm."
Toxic substances can get into water in different ways: from drains, together with underground waters, and even through the air. The SUSU chemists can detect them in concentrations below threshold values, even before they begin to harm humans. Continuous environmental monitoring using the method of the Chelyabinsk scientists is accessible, cheap and can be done in an express mode. There are no analogues to it yet, since it has not yet found wide practical application. It is important that all components for the work (from reagents to devices) can be easily manufactured in Russia.
This work is being carried out within the frameworks of the mega-grant "Innovations for Air and Water Purification, Carbon Footprint Reduction: Nanomaterials and Nanocomposites, Photocatalytic and Electrochemical Approaches". The research is financed by the Ministry of Science and Higher Education of the Russian Federation and South Ural State University and is being carried out as prat of the Science and Universities national project.