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The feasibility of oxidizing elemental mercury in coal combustion flue gas using catalytic material impregnated onto fabric filters was explored. TiO2, Au/TiO2, and Pd/Al2O3 were studied based on promising results in previous research. Several fabric coating methods were investigated to determine the best way to load a filter. A spray coat method was found to have the highest initial loading and had the lowest losses after simulated pulse-jet cleaning. The oxidation performance of the catalyst-coated filters was tested using a simulated flue gas in a bench-scale reactor under conditions similar to those found in a baghouse. Au/TiO2 and Pd/Al2O3 were effective, yielding mercury oxidation ranges of 40-60% and 50-80%, respectively. A 19 kW research combustor equipped with a baghouse was used to fire a range of coals and further test the performance of Pd/Al2O3. Results obtained warrant further development of this technique as a means of mercury pollution control.

Transient reaction techniques were combined with isotope labeling to study the reaction steps for the roomtemperature, photocatalytic oxidation (PCO) of ethanol on TiO 2 . Carbon-13 labeled ethanol (CH 3 13 CH 2 OH) was adsorbed on the catalyst and photocatalytically oxidized in the absence of gas-phase ethanol. The amounts of species remaining on the surface after PCO were determined by temperature-programmed oxidation. During PCO, only CO 2 and H 2 O formed for low coverages of ethanol, whereas acetaldehyde also desorbed for saturation coverage. Acetaldehyde forms rapidly from ethanol oxidation during PCO. At both low and high ethanol coverages, the R-carbon is preferentially oxidized and thus 13 CO 2 forms faster than 12 CO 2 at short illumination times. At longer times, the rates of 13 CO 2 and 12 CO 2 formation are nearly identical. The difference in behavior between 13 CO 2 and 12 CO 2 formation suggests two parallel reactions of ethanol, which may be due to two adsorption sites on TiO 2 .