The TG and zeta-potential characterization of silver-zeolite composites for anti-bacterial capability

The porous, stable zeolite materials impregnated with 1 wt% silver (AgZ) were used as anti-bacterial filters to reduce the bio-aerosols as bacterial counts in the indoor air quality of a medical facility to fulfill the regulation of the Taiwan environmental protection administration. The anti-bacterial efficacies of AgZ reach 99 % after 2 h of air circulation in rooms, and its capacity could be re-generated through heated air at 160 A degrees C. The stability and characteristics of AgZ were analyzed by the transmission electron microscopy, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, and zeta-potential. Heat of the endothermic reaction of AgZ was evaluated to be 377-388 J g(-1) and was discovered as stable below 300 A degrees C. The analysis results also showed the recovery of second isoelectric points at pH 8.5 of AgZ could represent the ability to adsorb negative charged bio-aerosols as well as anti-bacterial capacity.