Advanced Impregnanted Activated Carbons For Fuel Cell Air Purification

Abstract

Sulfur Dioxide (SO2) emissions is continuing to be an escalating issue as the world relies on burning fossil fuels to produce electricity and support transportation. SO2 can have severe health and environmental impacts, and is also capable of disrupting direct use of atmospheric air in emerging energy technologies. The focus of the project is to develop filter media with potential for the mitigation of SO2 in proton exchange membrane (PEM) fuel cells. PEM fuel cells require filters to be able to remove air contaminants because the contaminants can poison the catalyst and/or damage the cells which reduce the power production, ultimately shutting down the entire system. The current state of the art methods of gas contaminant mitigation are mostly non-regenerable or are absorbing pollutants at low rates. Consequently, there is a need to develop alternate sorbent materials that are capable of higher performance and with regeneration capabilities. To improve the current methods of air filtration technologies for SO2, potential sorbent material were tested including; urea, tetramethylurea, melamine, boric acid, 1-ethyl-3- methylimidazolium acetate ([EMIM][OAc]), zinc 1-ethyl-3-methylimidazolium acetate (Zn[EMIM][OAc]), magnesium 1-ethyl-3-methylimidazolium acetate (Mg[EMIM][OAc]), manganese 1-ethyl-3-methylimidazolium acetate (Mn[EMIM][OAc]), potassium hydroxide (KOH). Impregnating these sorbents onto activated carbon and testing their performance under simulated harsh polluted air environments with flows of 1-2 LPM (5-15 ppm SO2, clean air, 25˚C and 40-50% relative humidity) was performed. The results of gas sorption test showed that metallo ionic liquids presented improved filter media to some of the current industry sorbents.