Experimental modeling demonstrates photocatalytic methane degradation in air streams, indicating net climate benefits depend on leveraging pre-existing ultraviolet systems.
Key Points
To evaluate titanium dioxide-based photocatalytic oxidation of methane under varied ultraviolet-C intensities and model its practical feasibility and climate impact in ventilation systems.
Tested titanium dioxide (TiO2) photocatalysis on methane (2 to 10 ppm) across UV-C irradiance levels from 4 to 59 W/m².
Developed a kinetic and transport model validated against experimental methane data and literature values for formaldehyde and nitrogen oxides.
Modeled scale-up performance inside building ventilation ducts and calculated net lifecycle emissions in carbon dioxide equivalents (CO2e).
Laboratory testing at 2 ppm methane demonstrated a peak conversion efficiency of 24.4% and a maximum apparent quantum yield of 0.013%.
Full-scale ventilation modeling predicted conversion efficiency falling to approximately 0.017% as a result of thin boundary layers and short contact residence times.
Net-negative CO2e emission rates remain attainable if methane removal rates exceed emissions generated by catalyst production and UV-C power consumption.