Performance validation of a non-photocatalytic air purifier built by reactive adsorbent against a commercial UV-based air purifier

Abstract

A portable non-photocatalytic air purifier (AP) was built by modifying a honeycomb-type ceramic (HC) filter through immobilization of a reactive adsorbent (i.e., manganese dioxide (MnO2 (1 wt%))-Universitetet i Oslo (UiO)-66-amine (NH2): namely, M-U6N). This non-photocatalytic AP system was examined for the removal of gaseous formaldehyde (FA) at room temperature (RT) in a 17 L airtight chamber. The kinetic reaction rates (RW, μmol h−1 g−1) of AP (M-U6N), when measured at 10%, 50%, 90%, and 100% of its removal, were 631, 433, 191, and 114, respectively. This non-photocatalytic AP system fully mineralized FA to CO2 and H2O through the Mars–van Krevelen (MvK) mechanism with a significantly higher (i.e., 1.6–3.3 times) kinetic reaction rate (RF, μmol h−1 filter−1) than that of its UV-based AP counterpart. As such, based on our experimental performance validation, the non-photocatalytic AP system developed in this work was demonstrated to be superior to the commercial photocatalytic AP system in the treatment of gaseous FA. The findings of this study offer practical guidelines for the fabrication of cost-effective non-photocatalytic AP systems.