Investigation of PM2.5 Adsorption on Car Filters and Improvement of Their Adsorption Quality Using Polymeric and Composite Nanofibers

Particulate matter is one of the main air pollutants, especially in developing countries. Due to their small diameter, some of these particles are absorbed by the body and eventually entered the human circulatory or respiratory system. Since incomplete combustion of fuels are the main source of particulate matter, car occupants are particularly exposed to this pollution, especially in large city traffic. Therefore, the present study was conducted to evaluate the commercial filters in various vehicles in terms of the absorption of particulate matter less than 2.5 microns (PM2.5). Then polyacrylonitrile nanofiber and its composite with nano-chitosan were used to improve the ability to remove suspended particles by these filters .

First, a system was designed and built in the laboratory to measure the adsorption efficiency of PM2.5 and the pressure drop of filters. Then, six samples of various commercial cabin air filters and engine air filters were prepared and their PM2.5 adsorption was measured. The polymeric and composite nanofiber filters were made and their efficiency was investigated and finally, the results were compared.

For commercial engine air filters, the PM 2.5 adsorption was equal to zero and the absorption by cabin air filters was measured in the range of 5-8.33%. The adsorption was measured respectively 97 and 95% by polyacrylonitrile nanofiber and polyacrylonitrile composite nanofiber filter with nanochitosan .

 This study showed that the car filters were not able to remove PM2.5 but the polyacrylonitrile nanofiber filters were able to remove 95-97% of PM2.5. Therefore, by adding a layer of Nano-fiber introduced in this study to car filters, especially cabin filters, the PM2.5 removal efficiency can be improved, thus clean air is provided for car occupants.