Measurements and modeling of mercury and sulfur dioxide oxidation during selective catalytic reduction of nitric oxide

FUEL 83

Giang Tong1, Peter M. Walsh2, George A. Blankenship3, and Thomas K. Gale3. (1) Environmental Health Engineering Program, University of Alabama at Birmingham, Room BEC 257, 1530 3rd Avenue South, Birmingham, AL 35294-4461, (2) Department of Mechanical Engineering, University of Alabama at Birmingham, Room BEC 257, 1530 3rd Avenue South, Birmingham, AL 35294-4461, (3) Power Systems and Environmental Research Department, Southern Research Institute, 2000 9th Avenue South, Birmingham, AL 35205
Oxidation of elemental mercury to mercuric chloride was measured in the laboratory in a 286-mm-long sample of a square-cell monolithic catalyst for selective catalytic reduction of nitrogen oxides in fossil fuel combustion products. The gas mixture containing mercury was typical of coal combustion, including O2, CO2, H2O, NO, SO2, CO, HCl, and NH3 for reduction of NO. Oxidation of SO2 to sulfate was also measured. The extent of mercury oxidation was observed to depend on the CO mole fraction in the gas, decreasing from 71 ± 3% in the absence of CO to 43.5 ± 1% in the presence of 250 ppmv CO. Models based upon the mechanism and analysis by Niksa and Fujiwara for mercury oxidation (J. A&WMA 55, 2005, 1866) and by Svachula et al. for SO3 formation (Ind. Eng. Chem. Res. 1993, 32, 826) are able to explain important features of the behavior of the system.
 

Mercury and Other Trace Elements in Fuel: Emissions and Control
8:30 AM-11:45 AM, Monday, April 7, 2008 Morial Convention Center -- Rm. 238, Oral

Division of Fuel Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008