Development of a semi-automatic station for monitoring concentrations of organic pollutants in urban air by chromatographic methods

Relevance of the project:

Worldwide, air pollution and indoor air pollution are considered major sources of health risk. One of the main stages in reducing the negative impact of air pollution is its monitoring. The currently used standard methods for determining volatile organic compounds (VOCs) are based on air sampling in containers or capturing VOCs with sorption tubes. These methods are very complex, labor-intensive, and require expensive thermal desorbers and cryogenic focusing devices, which significantly limits their application and monitoring effectiveness.
The most promising method for determining VOCs in the air is solid-phase microextraction (SPME). The SPME method is based on the sorption of VOCs by a micro-polymer coating followed by desorption of analytes directly into the gas chromatograph sample introduction device. In SPME, analyte desorption occurs almost instantly in the gas chromatograph evaporator, and cryofocusing is not required. Using SPME, more than 100 VOCs have been identified in the air of Almaty city.
For atmospheric air monitoring, the determination of time-weighted average concentrations of VOCs is of utmost importance, which can be determined by SPME in a protective needle. However, the main disadvantage of this approach is insufficient accuracy caused by competition between analytes, uncontrolled sorption of analytes on the metal parts of the holder, and the influence of temperature. The applicability of the method is also limited by the complexity of calibration.
Within the framework of this project, a semi-automatic station for monitoring VOC concentrations in atmospheric air based on SPME with controlled air supply and thermostating will be developed. To select the optimal station design, 3 prototypes using different methods of air supply to the extraction chamber will be developed and tested. A faster, simpler, and more efficient calibration method will be developed, and the possibility of conducting calibration directly in the station during air sampling will be considered.