Advertisement

Sulfur Forms Determination in Coal Using Microwave Discharge Activated Oxygen and Mössbauer Spectroscopy

  • James L. Giulianelli
  • D. L. Williamson

Abstract

The use of a microwave discharge to activate oxygen for the low temperature ashing of coal is being tested. The effect of low temperature ashing (LTA) by the normal radiofrequency procedure and this new microwave procedure upon the Fe-S compounds is monitored by the use of 57Fe Mössbauer spectroscopy. Results show that the microwave technique, like the normal LTA procedure, effectively ashes the coal without the oxidation of pyritic sulfur. Dehydration of iron sulfates and oxidation of Fe2+ to Fe3+ in sulfates occurs in both ashing procedures under the conditions tested. Separate experiments show that dehydration is caused by sample heating rather than by reaction with the activated oxygen. The Mossbauer recoilless fractions of the Fe-sulfates observed in this study are found to be only about half that of pyrite.

Keywords

Mossbauer Spectroscopy Coal Sample Organic Sulfur Coal Product Microwave Discharge 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Frazer, F.W. and Belcher, C.B., 1973, Quantitative determination of the mineral-matter content of coal by a radiofrequency-oxidation technique, Fuel, 52: 41.CrossRefGoogle Scholar
  2. Given, P.H. and Yarzab, R.F., 1978, Analysis of the organic substance of coals: problems posed by the presence of mineral matter, in: “Analytical Methods for Coal and Coal Products,” Vol. 11, C. Karr, Jr., ed., Academic Press, New York.Google Scholar
  3. Gladfelter, W.L. and Dickerhoof, D.W., 1976, Determination of sulfur forms in hydrodesulfurized coal, Fuel, 55: 360.CrossRefGoogle Scholar
  4. Gluskoter, H., 1965, Electronic low-temperature ashing of bituminous coal, Fuel, 44: 285.Google Scholar
  5. Hamersma, J.W. and Kraft, M.L., 1979, Coal Sulfur Measurements, EPA-600/7-79-150.Google Scholar
  6. Huffman, G.P. and Huggins, F.E., 1978, Mossbauer studies of coal and coke: quantitative phase identification and direct determination of pyritic and sulphide sulphur content, Fuel, 57: 592.CrossRefGoogle Scholar
  7. Huggins, F.E. and Huffman, G.P., 1979, Mossbauer analysis of iron-Google Scholar
  8. bearing phases in coal, coke, and ash, in: “Analytical Methods for Coal and Coal Products,” Vol. Ill, C. Karr, Jr., ed., Academic Press, New York.Google Scholar
  9. Jacobs, T.S. and Levinson, L.M., 1979, Enhancement of magnetic separability in coal liquefaction residual solids, J. Appl. Phys., 50: 2422.CrossRefGoogle Scholar
  10. Jenkins, R.G. and Walker, P.L., Jr., 1978, Analysis of mineral matter in coal, in: “Analytical Methods for Coal and Coal Products,” Vol. II, C. Karr, Jr., ed., Academic Press, New York.Google Scholar
  11. Miller, R.N., Yarzab, R.F., and Given, P.H., 1979, Determination of the mineral-matter contents of coals by low-temperature ashing, Fuel, 58: 4.CrossRefGoogle Scholar
  12. Montano, P., 1979, Characterization of iron bearing minerals in coal, in: “Preprints Amer. Chem. Soc.-Div. Fuel Chem.,” 24: 218.Google Scholar
  13. Montano, P.A., 1980, Application of Mossbauer spectroscopy to coal characterization and utilization, in: “Recent Chemical Applications of Mossbauer Spectroscopy,” A.C.S. Symposium Series, C.K. Shenoy and V.G. Stevens, ed., American Chemical Society, Washington, D.C., in press.Google Scholar
  14. Palache, C., Berman, H., Frondel, C., 1951, “Dana’s System of Minerology,” Vol. II, John Wiley and Sons, New York.Google Scholar
  15. Paris, B., 1977, The direct determination of organic sulfur in raw coals, in: “Coal Desulfurization, Chemical and Physical Methods,” A.C.S. Symposium Series 64, T.D. Wheelock, ed., American Chemical Society, Washington, D.C.Google Scholar
  16. Saporoschenko, Mykola, Hinckley, C.C., Smith, G.V., Twardowska, H., Shiley, R.H., Griffin, R.A., and Russell, S.J., 1980, Mossbauer spectroscopic studies of the mineralogical changes in coal as a function of cleaning, pyrolysis, combustion and coal-conversion processes, Fuel, 59: 567.CrossRefGoogle Scholar
  17. Weast, Robert C., ed., 1977–78, “CRC Handbook of Chemistry and Physics,” 58th edition, CRC Press, Inc., Florida.Google Scholar
  18. Williamson, D.L., Guettinger, T.W., and Dickerhoof, D., Quantitative investigations of coal, in: “Recent Chemical Applications of Mössbauer Spectroscopy,” A.C.S. Symposium Series, C.K. Shenoy and V.G. Stevens, ed., American Chemical Society, Washington, D.C., in press.Google Scholar

Copyright information

© Plenum Press, New York 1982

Authors and Affiliations

  • James L. Giulianelli
    • 1
    • 2
  • D. L. Williamson
    • 1
    • 2
  1. 1.Department of Chemistry/GeochemistryColorado School of MinesGoldenUSA
  2. 2.Department of PhysicsColorado School of MinesGoldenUSA

Personalised recommendations