Triboelectrification-based particulate matter capture utilizing electrospun ethyl cellulose and PTFE spheres
Minhee Cho, Vishwanath Hiremath, Jeong Gil Seo
Abstract
Air pollution associated with particulate matter (PM) has become one of the most serious environmental problems of the decade. Fibrous filters and electrostatic precipitators are usually employed to the indoor PM removal. In case of fibrous filter, if PM is smaller than the hole of filter, removal efficiency decreases considerably whereas, electrostatic precipitator has fatal drawback of producing unwanted O3. In this study, triboelectric PM capture system was introduced by utilizing integrated mechanical filtration attributed to structural characteristic of electrospun ethylcellulose (EC) and the electrostatic filtration induced by the direct triboelectrification between electrospun EC and polytetrafluoroethylene (PTFE) spheres. The electrospun EC was reinforced by heating above glass transition temperature (Tg) to improve mechanical strength. Further, the triboelectrification between EC and PTFE achieved 100% PM removal efficiency and can eliminate the drawback of mechanical filtration without production of any hazardous substances. The improvement of PM removal efficiency by the triboelectrification were +6.68%, +6.89% and +5.47%, corresponding to PM1, PM2.5 and PM10 respectively. More importantly, it was observed that the triboelectric contribution was much higher for small PM which benefits overall system.