Adsorption of Vapor Phase Mercury on Various Carbons

Jinjing Luo, A. M. Hein, J.Y. Hwang

3Dept. of Materials Science & Engineering,Michigan Technological University, Houghton, MI 49931, U. S. A..
Dept. of Civil & Environmental Engineering Michigan Technological University, Houghton, MI 49931, U. S. A..
Institutue of Materials Processing Michigan Technological University, Houghton, MI 49931, U. S. A..

DOI: 10.4236/jmmce.2004.31002                

Abstract

Unburned carbon was found to be a component of fly ash resulting from incomplete combustion in a pulverized-coal based power plant. Previous investigations found that unburned carbon separated from fly ash exhibited good mercury adsorption property. It would offer an opportunity to substitute activated carbon with low cost unburned carbon for mercury adsorption from power plant emission gases. This study provides a comparison of mercury adsorption by carbon from various sources, including activated carbon and unburned carbon from two different power plants. The experimnts were conducted under various temperatures and mercury concentrations to determine whether good mercury adsorption properties can be obtained from various carbon sources. This study revealed that mercury adsorption depended on the carbon sources and conditions. Activated carbon (F400) demonstrated the best mercury absorbability among the three tested carbons, followed by AEP unburned carbon. Pepco unburned carbon showed very little mercury absorbability. Increasing the temperature generally resulted in the decrease of mercury adsorption. Adsorption rate could be effectively increased with increasing gaseous Hg concentration. Desorption treatment before adsorption test could improve unburned carbon’s adsorption capacity, especially for Pepco carbon.

Keywords

Mercury, Adsorption, Activated Carbon, Unburned Carbon

Conflicts of Interest

The authors declare no conflicts of interest.

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