Final Report: Development of Mercury Sampling and Analytical Techniques

EPA Grant Number: R827649C013
Subproject: this is subproject number 013 , established and managed by the Center Director under grant R827649
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: Center for Air Toxic Metals® (CATM®)
Center Director: Groenewold, Gerald
Title: Development of Mercury Sampling and Analytical Techniques
Investigators: Pavlish, John H. , Benson, Steven A. , Galbreath, Kevin C. , Timpe, Ronald C. , Zygarlicke, Christopher J. , Hassett, David J. , Holmes, Michael J. , Miller, Stanley J. , Laudal, Dennis L. , Olson, Edwin S. , Thompson, Jeffrey S. , Heebink, Loreal V. , Ralston, Nicholas V.C. , Mibeck, Blaise , Kong, Lingbu
Institution: University of North Dakota
EPA Project Officer: Chung, Serena
Project Period: October 15, 1999 through October 14, 2004
RFA: Center for Air Toxic Metals (CATM) (1998) RFA Text |  Recipients Lists
Research Category: Targeted Research

Objective:

The objective of this research project was to address air toxic trace element emissions, which have become a matter of worldwide concern as well as a regulatory issue in the United States. The specific objective of this research project was to develop and disseminate critical information on air toxic metal compounds to support development and implementation of pollution prevention and control strategies that will reduce effectively air toxic metal emissions and releases to the environment.

Summary/Accomplishments (Outputs/Outcomes):

Development of novel identification and quantification methods for inorganic mercuric (Hg2+) compounds in coal combustion flue gas was attempted using cryogenic, resin, and solvent trapping of certain volatile Hg2+ compounds, as well as their analysis by mass spectrometry. Efforts were focused on HgCl2 and HG(NO3)2. Development of a special method was required to make the difficult transfer from the cryotrap to the mass spectrometer. The analysis of HgCl2 was improved by derivatizing cryo-trapped HgCl2 with diazomethane to form bischloromethylmercury, whose peak shape is very sharp in contrast to the very broad elution of HgCl2. The high reactivity of Hg(NO3)2 resulted in loss of material on the trapping surfaces and spurious gas chromatography-mass spectometry spectra resulting from on-column reactions. Novel derivatization methods still are needed to resolve this problem.

The effectiveness of using high-altitude weather balloons to sample atmospheric reactive gas Hg was evaluated. The total amounts of Hg collected during three flights were extremely small. The mission durations were less than 3 hours, and the maximum altitude sampled was 75,400 feet. The distribution of atmospheric Hg concentrations ranged from 0.03 to 1.4 ng/m3. Concentrations were highest nearer the ground surface and decreased with altitude to less than 0.2ng/m3.

A new method to measure accurately Cl in coals possessing less than 200 ppm Cl was developed because conventional methods lack sensitivity. In addition, Cl species (Cl, HCl, and Cl2) generally are assumed to be the dominant Hg0 reactants in coal combustion flue gas.

Improved methods for sampling and analyzing halogen species in coal combustion flue gas were investigated. U.S. Environmental Protection Agency Method 26A was shown to be biased toward a high measurement of HCl and a low value for Cl2 because of a reaction between SO2 and Cl2 in the impinger solution. Laboratory evaluation of instruments for detecting F2 in flue gas indicated that either a colorimetric method or a specific-ion electrode method could be used, but that the latter would be recommended based on cost, sensitivity, and interferences. The measurement of F2 in the combustion zone would have to be accomplished by in situ measurement using laser spectroscopy because of the rapid reaction of elemental F with water vapor and other flue gas components at lower temperatures.

Supplemental Keywords:

air, air quality, analysis, control, emissions, environment, hazardous, measurement, mercury, metals, modeling, pollutants, pollution, sampling, species, toxic, transformations,, RFA, Scientific Discipline, Toxics, Air, Waste, Chemical Engineering, air toxics, Environmental Chemistry, HAPS, Incineration/Combustion, 33/50, Engineering, Chemistry, & Physics, Environmental Engineering, monitoring, flue gas , mercury , mercury, selective catalytic reduction, coal fired utility boiler , sampling tools, gas chromatography, mercury speciation, mercury speciation and sampling, speciation tools, mercury & mercury compounds, Mercury Compounds, flue gas emissions

Relevant Websites:

http://www.undeerc.org Exit
http://www.undeerc.org/catm/index.html Exit

Progress and Final Reports:

Original Abstract
  • 2000
  • 2001
  • 2002
  • 2003 Progress Report

  • Main Center Abstract and Reports:

    R827649    Center for Air Toxic Metals® (CATM®)

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R827649C001 Development And Demonstration Of Trace Metals Database
    R827649C002 Nickel Speciation Of Residual Oil Ash
    R827649C003 Atmospheric Deposition: Air Toxics At Lake Superior
    R827649C004 Novel Approaches For Prevention And Control For Trace Metals
    R827649C005 Wet Scrubber System
    R827649C006 Technology Commercialization And Education
    R827649C007 Development Of Speciation And Sampling Tools For Mercury In Flue Gas
    R827649C008 Process Impacts On Trace Element Speciation
    R827649C009 Mercury Transformations in Coal Combustion Flue Gas
    R827649C010 Nickel, Chromium, and Arsenic Speciation of Ambient Particulate Matter in the Vicinity of an Oil-Fired Utility Boiler
    R827649C011 Transition Metal Speciation of Fossil Fuel Combustion Flue Gases
    R827649C012 Fundamental Study of the Impact of SCR on Mercury Speciation
    R827649C013 Development of Mercury Sampling and Analytical Techniques
    R827649C014 Longer-Term Testing of Continuous Mercury Monitors
    R827649C015 Long-Term Mercury Monitoring at North Dakota Power Plants
    R827649C016 Development of a Laser Absorption Continuous Mercury Monitor
    R827649C017 Development of Mercury Control Technologies
    R827649C018 Developing SCR Technology Options for Mercury Oxidation in Western Fuels
    R827649C019 Modeling Mercury Speciation in Coal Combustion Systems
    R827649C020 Stability of Mercury in Coal Combustion By-Products and Sorbents
    R827649C021 Mercury in Alternative Fuels
    R827649C022 Studies of Mercury Metabolism and Selenium Physiology