VOCs pollution characteristics and potential of ozone generation in Kaifeng City

In recent years, the exhausted gas from factories has become an important part of environmental pollution in Kaifeng City. Air samples were collected for 57 kinds of volatile organic compounds (VOCs) and 13 kinds of aldehydes and ketones from the Cancer Hospital of Kaifeng city between May and October 2019. The pollutants were measured by gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC) technique. Combined with the 8-hour automatic monitoring data of air ozone automatic monitoring at this sampling site, a total of 31 observations on volatile organic compounds (VOCs) were carried out over between May and October 2019. The results showed that the average concentration of VOCs was in the order of oxygen-containing organic matters > alkanes > olefins > aromatic hydrocarbons > alkynes. Using SPSS26 statistical software, representative key species were selected from VOCs, and correlation analysis was conducted with ozone concentration and meteorological factors. The ozone concentration was significantly correlated with air temperature. Acrolein & propionaldehyde, acetaldehyde, and formaldehyde, had a significant negative correlation with ethylene and ethane. The highest ethylene and ethane concentrations appeared when there was west wind, while toluene showed a significantly high value in the southwest wind. The oxygenated organics had obvious wind direction characteristics and the four kinds of oxygenated organics were rarely affected by the west, northwest and north winds.