Photooxidation potential of fine particles from desulfurization flue gas aerosol

In China, desulfurization flue gas from coal-fired power plants (CFPPs) has been the focus of research for many years. In this study, for the first time, we simulated the emission process of flue gas and prepared photocatalysts by deposition. An innovative photocatalytic perspective was applied to study the composition, photocatalytic properties, hygroscopicity, and redox properties of the fine particles from flue gas aerosols. The characterization results of XRD, HRTEM, and XPS of freeze-dried desulfurized flue gas samples indicated that aerosol condensation occurred during the smoke plume transportation process, resulting in the formation of well-crystallized fine particles primarily consisting of soluble salts and metal oxides. The UV-vis and ESR results confirmed that desulfurized flue gas has UV light utilization and photocatalytic potential for producing oxidation groups such as hydroxyl radicals and superoxide radicals in light. The subsequent photocatalyst experiments revealed an 85.4 % reduction of 7 ppm isoprene in 30 min; ozone production (373 mu g/m3) was observed under more complicated conditions (NO2 = 80 ppb, VOCs = 7 ppm). As a result of the study, a new research approach was proposed for exploring the photoactive potential of flue gas aerosol produced by CFPPs, as well as its impact on the concentration of VOCs and ozone. The finding provided a new possible pathway for desulfurization flue gas emissions and a reference for future research on the observation and control of atmospheric pollution.

Automated summary

In this study, the emission process of desulfurization flue gas from coal-fired power plants (CFPPs) was simulated and photocatalysts were prepared. The composition, photocatalytic properties, hygroscopicity, and redox properties of the fine particles from flue gas aerosols were investigated. The results showed that well-crystallized fine particles consisting of soluble salts and metal oxides were formed during the transportation process of smoke plumes. The desulfurized flue gas exhibited UV light utilization and photocatalytic potential for oxidation reactions. The findings provide insights into the photoactive potential of CFPPs' flue gas aerosol and its impact on VOCs and ozone concentration.