Photodegradation of gaseous toluene and disinfection of airborne microorganisms from polluted air using immobilized TiO2 nanoparticle photocatalyst-based filter

摘要

Photocatalytic oxidation (PCO) has been described as an advanced technology to remove toxic volatile organic compounds (VOCs) and airborne microorganisms from indoor air environments. This technique is economic, stable, safe, and capable to remove a wide variety of organic contaminants under UV irradiation. This study presents a case study on the effect of a fabricated filter in the removal of toluene at 26 mg/L and disinfection of ambient air under a given operating condition. The principal goals of this study were to synthesize Ag nanoparticles/TiO2 filter for the first time via the deposition of Ag nanoparticles on a commercial immobilized TiO2 tissue sheet by impregnation technique and to investigate the performance of this prepared Ag/TiO2 tissue based filter system for toluene removal as well as to remove airborne microorganisms from indoor air. The results illustrated that under the experimental conditions, Ag/TiO2-based filter was able to disinfect well the microorganisms. The performance of Ag/TiO2 filter shows two different stages; the first one is a slight adsorption phase in dark with approximately 15% of toluene removal within 60 min. The second stage is a photooxidation phase under UV irradiation in which the toluene removal efficiency was significantly enhanced with extension of the operational time and reached 97% during this stage. Additionally, the Ag/TiO2 filter has a higher disinfection capacity of airborne microorganisms that completely removed to reach 100% after 300 min of application. This filter could be practically introduced as an effective system in industrial, hospital, and home applications for air purification.