Antibacterial and Regenerated Characteristics of Ag-zeolite for Removing Bioaerosols in Indoor Environment

The antibacterial reaction rate k(t) (CFU/g-hr) and total antibacterial capacity q(T) (CFU/g) were calculated to evaluate the performance of antibacterial Ag-zeolite (AgZ) with a series of experiments. The continuous antibacterial reactions at 10 and 80 hr were respectively repeated nine times to evaluate the AgZ antibacterial ability. An antibacterial system was conducted in a fixed bed reactor packed with AgZ to reduce bacterium and fungus counts in the indoor environment. The AgZ used in this study was prepared in two steps including Y-type zeolites synthesis and Ag ion-exchange. X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) were carried out to identify the characteristic of AgZ. The results demonstrated that the antibacterial efficiencies of 1, 2 and 3 wt% AgZ against bacterium and the fungus were all higher than 95% after 120 min of operation, and 1 wt% AgZ was considered to be more cost-effective since its antibacterial efficiency could approach 90% in less than 60 min. The 1 wt% AgZ had excellent performance repeated usage up to nine times.