Ecology & Safety, Volume 16, 2022

Abstract: The air purification performance of an aerial plant based biofilter was investigated in this study, as an alternative option to the more common botanical biofilters that are mainly based on terrestrial plants. The experiments have been carried out by using a mixture of different plant species from Tillandsia genus for carbon dioxide (the model contaminant) removal from atmospheric air, under different operating conditions (air flowrate, plant density, lighting conditions). The CO2 removal efficiency was light dependent and significantly influenced by the air flowrate. Additionally, individual plant species (T. xerographica) was also assessed at a higher gas-plant contact time, reaching about 80% CO2 removal efficiency. Further exploring this CO2 capture potential, along with the possibility to remove other contaminants as well, can be envisaged in future studies for developing such biosystems for special applications (e.g., mitigation of gaseous pollutants from auto traffic etc.). Particularly, such aerial plant doesn’t require a soil substrate for growing, reducing the biofilter maintenance and allowing a better process control, which may make it an interesting candidate for space applications, as well.