Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Carbon sorption of trace mercury species

Book ·
OSTI ID:43241
; ;  [1]
  1. Univ. of North Dakota, Grand Forks, ND (United States). Energy and Environmental Research Center
Coal-fired power utilities may register mercury concentrations of 2--15 {mu}g/Nm{sup 3} in the flue gas stream, but waste incinerator flue gas may contain up to 1,000--2,000 {mu}g/Nm{sup 3}. To remove trace amounts of mercury species, activated carbons are used, especially in the waste incineration industry. However, carbon removal efficiency depends on the nature of the carbons, mercury speciation, and condition in the capture region. Recently, Metzger and Braun, and others, have shown that activated carbon only partially adsorbs elemental mercury from the gas stream. On the other hand, Metzger and Braun indicated that activated carbon adsorbs virtually all mercuric chloride (HgCl{sub 2}) at 200 C, partial breakthrough occurring at about 250 C. Iodized activated carbon, however, adsorbs mercury vapor, forming thermally stable mercuric iodide. Their results suggest that iodized carbon also has enhanced sorption capacity for HgCl{sub 2}. Quantitative adsorption was demonstrated for both mercury species at temperatures up to 180 C. The carbon sorption process is affected by the presence of other components in the flue gas. For example, Hall and others have reported that oxygen influences the interaction process over the temperature range of 100--300 C. The preliminary results reported herein on the capture of mercury species by two carbon sorbents are from a major program at the EERC on air toxic emissions.
OSTI ID:
43241
Report Number(s):
CONF-940930--
Country of Publication:
United States
Language:
English