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Photocatalytic Degradation of Air Emissions from Municipal Solid Waste Landfills Original Article, C21 Mita S. Upadhyay, Melanie L. Sattler Journal. Civil Eng. Urban. 3(4):128-135. 2013 ABSTRACT:This study examined the potential for photocatalytic oxidation to treat pollutants landfill gas (LFG). Three example LFG constituents were tested: methane, xylenes, and carbonyl sulfide. Methane, which comprises 40-60% of landfill emissions, is flammable and explosive at high concentrations, and is a greenhouse gas with global warming potential of 22 times that of carbon dioxide (100 year time horizon). Xylenes represent the second-highest concentration of hazardous air pollutants in LFG, and also contribute to ground-level ozone formation. Carbonyl sulfide was chosen as an example of a LFG constituent that is a hazardous air pollutant, as well as an odor-causing compound. Reaction rate constants are necessary for photocatalytic reactor design; accordingly, rate constants were determined for the compounds of interest over Degussa P-25 titanium dioxide (TiO2) catalyst in a continuous mixed-batch reactor. Plots of compound concentration versus time indicated first-order decay for all compounds tested. Destruction rates were higher for the smaller molecules methane and carbonyl sulfide and lower for the more complex xylenes. The destruction rates for methane were found to depend on relative humidity. The research concludes that photocatalytic oxidation is a potentially promising method to treat emissions from landfills. Keywords:Carbonyl Sulphide, Landfill Gas, Methane, Photocatalytic Oxidation, Xylene منبع: [Hidden Content] دانلود: [Hidden Content].,21-128-135.pdf J. Civil Eng. Urban.,21-128-135.pdf