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Research on Chemical Intermediates

, Volume 28, Issue 7–9, pp 857–870 | Cite as

Fundamental photochemical approach to the concepts of fluence (UV dose) and electrical energy efficiency in photochemical degradation reactions

  • James R. Bolton
  • Mihaela I. Stefan
Article

Abstract

For photochemical reactions in a quasi collimated beam, derivations are presented that introduce 'rate constants' based on the fluence (UV dose) received within the irradiated solution. These fluence-based 'rate constants' are shown to be fundamental and depend only on the quantum yield and the molar absorption coefficient at the irradiation wavelength. An experimental example is given, where the quantum yield for the photolysis of atrazine is determined to be 0.033. The new concepts are developed further to analyze the Figure-of-Merit Electrical Energy per Order (EEO), and it is shown that the EEO depends on the same fundamental photochemical parameters. An example of the photolysis of N-nitrosodimethylamine (NDMA) is presented, and it is shown that the EEO should decrease (increased electrical energy efficiency) as the radius of the UV reactor increases (increased path length), and should increase as the percent transmittance of the water decreases.

Keywords

Energy Efficiency Quantum Yield Photolysis Atrazine Photochemical Reaction 
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.

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REFERENCES

  1. 1.
    R. P. Schwarzenbach, P. M. Gschwend and D. M. Imboden, Environmental Organic Chemistry, Chapter 13. JohnWiley & Sons, Inc., New York (1993).Google Scholar
  2. 2.
    A. Leifer, The Kinetics of Environmental Aquatic Photochemistry. ACS Professional Reference Book (1988).Google Scholar
  3. 3.
    R. G. Zepp, Environ. Sci. Technol. 12 (3), 327-329 (1978).Google Scholar
  4. 4.
    R. G. Zepp, Experimental approaches to environmental photochemistry, in: The Handbook of Environmental Chemistry, O. Hutzinger (Ed.), Vol. 2, Part B. Springer, Berlin (1982).Google Scholar
  5. 5.
    R. G. Zepp and D. M. Cline, Environ. Sci. Technol. 11, 359-366 (1977).Google Scholar
  6. 6.
    W. R. Haag and T. Mill, Environ. Toxicol. Chem. 6, 359-369 (1987).Google Scholar
  7. 7.
    K. Nick, H. F. Schoeler, G. Mark, T. Söylemez, M. S. Akhlaq, H.-P. Schuchmann and C. von Sonntag, J. Water SRT-Aqua 41, 82-87 (1992).Google Scholar
  8. 8.
    J. R. Bolton, Terms and de. nitions in ultraviolet disinfection, in: Proceedings, Disinfection 2000: Disinfection of Wastes in the New Millennium. New Orleans, LA, Water Environment Federation, 601Wythe St., Alexandria,VA, 22314 (2000).Google Scholar
  9. 9.
    J. W. Verhoeven, Pure Appl. Chem. 68, 2223-2286 (1996) (available on the Web at http://www.unibas.ch/epa/welcome.html).Google Scholar
  10. 10.
    J. R. Bolton and R. G. Linden, J. Environ. Engng. (2002) (in press).Google Scholar
  11. 11.
    H. J. Morowitz, Science 111, 229-230 (1950).Google Scholar
  12. 12.
    D. P. Hessler, V. Gorenflo and F. H. Frimmel, Acta Hydrochim. Hydrobiol. 21, 209-214 (1993).Google Scholar
  13. 13.
    D. P. Hessler, V. Gorenflo and F. H. Frimmel, Aqua (London) 42, 8-12 (1993).Google Scholar
  14. 14.
    F. J. Beltran, G. Ovejero and B. Acedo, Wat. Res. 27, 1013-1021 (1993).Google Scholar
  15. 15.
    J. R. Bolton, K. G. Bircher, W. Tumas and C. A. Tolman, Pure Appl. Chem. 73 (4), 627-637 (2001).Google Scholar
  16. 16.
    J. R. Bolton, Wat. Res. 34, 3315-3324 (2000).Google Scholar
  17. 17.
    L. R. Koller, in: Ultraviolet Radiation, S. S. Ballard (Ed.), 2nd edn, Chapter 6, p. 200. Wiley & Sons, Inc., New York (1965).Google Scholar
  18. 18.
    C. M. Sharpless, C. I. Chou, A. A. Mo. di and K. G. Linden, N-nitrosodimethylamine removal from drinking water by UV-treatment: a direct comparison of different UV technologies, in: Proceedings of Water Quality and Technology Conference, Nashville, TN (2001).Google Scholar

Copyright information

© VSP 2002 2002

Authors and Affiliations

  • James R. Bolton
  • Mihaela I. Stefan

There are no affiliations available

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