Golden Pothos viability in engineered mixed bed growth media containing ionic liquids for plant-based building air filtration systems

The viability of the Golden Pothos (Epipremnum aureum) plants in different formulations of engineered growth media were evaluated for application in plant-based air filtration systems. To enhance filtration capability, the growth media was engineered to improve toxin capture ability with the aim of maintaining a plant-friendly environment. The growth media used in this study was a hydroponic media composed of activated carbon and porous glass (Growstone). Wet granulation was performed to create a mixed bed of the growth media composed of 40% activated carbon and 60% Growstone. Ionic liquids were tethered to the activated carbon to enhance the toxin capacity and selectivity and then granulated with Growstone to form the enhanced growth media. Two ionic liquids were utilized in this study: 1-butylpyridinium bis(trifluoromethylsulfonyl)imide and choline bis(trifluoromethylsulfonyl)imide, and were selected for their air toxin absorption capacity and reported low toxicity. Eighteen Golden Pothos plants were transplanted to hydroponic and monitored over a period of 40 days in the engineered growth media. Plant metrics were qualitatively and quantitatively analyzed. No statistical difference in normalized growth by % weight gain between the ionic-liquid containing media and the ionic liquid-free growth media was found, however, a statistical difference was observed between the 1-butylpyridinium bis(trifluoromethylsulfonyl)imide and the choline bis(trifluoromethylsulfonyl)imide containing growth medias. The results of this study illustrate that any ionic liquids identified as good candidates based upon their air filtration ability and basic toxicity studies need to be evaluated first for plant viability before studying the efficacy of the full plant-based air filtration system for toxin removal.