Journal of Polymers and the Environment

, Volume 26, Issue 8, pp 3283–3293 | Cite as

Photochemical Kinetic Modeling of Degradation of Aqueous Polyvinyl Alcohol in a UV/H2O2 Photoreactor

  • Dina Hamad
  • Mehrab Mehrvar
  • Ramdhane DhibEmail author
Original Paper


This study presents a photochemical kinetics model to describe the degradation of water-soluble PVA (Polyvinyl Alcohol) polymer in a UV/H2O2 batch reactor. Under the effect of UV light, the photolysis of hydrogen peroxide into hydroxyl radicals can generate a series of polymer scission reactions. For a better understanding and analysis of the UV/H2O2 process in the cracking of the PVA macromolecules, a chemical reaction mechanism of the degradation process and a relevant photochemical kinetics model are developed to describe the disintegration of the polymer chains. Taking into account the probabilistic fragmentation of the polymer, the statistical moment approach is used to model the molar population balance of live and dead polymer chains. The model predicts the PVA molecular weight reduction, the acidity of the solution, and hydrogen peroxide residual. In addition to previously published data collected in this laboratory, a new set of experiments were conducted using a 500 mg/L PVA aqueous for different hydrogen peroxide/PVA ratios for model validation. Measurements of average molecular weights of the polymer, hydrogen peroxide concentrations and pH of the PVA solution were determinant factors in constructing a reliable photochemical model of the UV/H2O2 process. Experimental data showed a decrease in the PVA molecular weight and a buildup of the solution acidity. The experimental data also served to determine the kinetics rate constants of the PVA photochemical degradation and validate the model whose predictions are in good agreement with data. The model can provide a comprehensive understanding of the impact of the design and operational variables.


Modeling of photodegradation Population balance PVA molecular weight Free radical-induced degradation UV/H2O2 process 



The financial support of the Natural Sciences and Engineering Research Council of Canada (NSERC) and Ryerson University is greatly appreciated.


  1. 1.
    Aarthi T, Shaama M, Madras G (2007) Ind Eng Chem Res 46:6204–6210CrossRefGoogle Scholar
  2. 2.
    Tayal A, Khan S (2000) Macromol 33:9488–9493CrossRefGoogle Scholar
  3. 3.
    Swift G (1997) Polym Degrad Stab 59:19–24CrossRefGoogle Scholar
  4. 4.
    Alfano O, Cassano A (2009) Scaling-up of photoreactors: applications to advanced oxidation processes. INTRC Publishers, Massachusetts, 229–286Google Scholar
  5. 5.
    Mohajerani M, Mehrvar M, Ein-Mozaffari F (2009) Int J Eng 3:120–146Google Scholar
  6. 6.
    Hamad D, Dhib R, Mehrvar M (2016) J Polym Environ 24:72–83CrossRefGoogle Scholar
  7. 7.
    Ghafoori S, Mehrvar M, Chan PS (2012) Ind Eng Chem Res 51:14980–14993CrossRefGoogle Scholar
  8. 8.
    Santos L, Poli A, Cavalheiro C, Neumann M (2009) J Braz Chem Soc 20:1467–1472CrossRefGoogle Scholar
  9. 9.
    McCoy B, Madras G (2001) Chem Eng Sci 56:2831–2836CrossRefGoogle Scholar
  10. 10.
    Solaro A, Corti A, Chillini E (2000) Polym Adv Technol 11:873–878CrossRefGoogle Scholar
  11. 11.
    Ghafoori S, Mehrvar M, Chan P (2011) Chem Eng J 245:133–142CrossRefGoogle Scholar
  12. 12.
    Hamad D, Mehrvar M, Dhib R (2014) Polym Degrad Stab 103:75–82CrossRefGoogle Scholar
  13. 13.
    Hamad D, Dhib R, Mehrvar M (2016) Environ Technol 37(21):2731–2742CrossRefPubMedGoogle Scholar
  14. 14.
    Christensen H, Sehested K, Corfitzen H (1982) J Phys Chem 86:1588–1590CrossRefGoogle Scholar
  15. 15.
    Buxton G, Greenstock C, Helman W, Ross A (1988) Phys Chem Ref Data 17:513–886CrossRefGoogle Scholar
  16. 16.
    Liao C, Gurol M (1995) Environ Sci Technol 29:3007–3014CrossRefPubMedGoogle Scholar
  17. 17.
    Crittenden JC, Hu S, Hand DW, Green SA (1999) Water Res 33:2315–2328CrossRefGoogle Scholar
  18. 18.
    Weinstein J, Bielski B (1979) Am Chem Soc 101:58–62CrossRefGoogle Scholar
  19. 19.
    Bielski B, Cabelli D (1991) Int J Radiat Bio 59:291–319CrossRefGoogle Scholar
  20. 20.
    Elliot A, Buxton G (1992) Chem Soc 88:2465–2470Google Scholar
  21. 21.
    Linden K, Sharpless C, Andrews S, Atasi K, Korategere V, Stefan M, Suffet I (2005) Innovative UV technologies to oxidize organic and organoleptic chemicals. IWA Publishing, LondonGoogle Scholar
  22. 22.
    Whittmann G, Horvath I, Dombi A (2002) Ozone Sci Eng 24:281–291CrossRefGoogle Scholar
  23. 23.
    Kodera Y, McCoy B (1997) AIChE J 3205–3214Google Scholar
  24. 24.
    Metha K, Madras G (2001) Am Inst Chem Eng J47:2539–2545Google Scholar
  25. 25.
    Smagala T, McCoy B (2003) Ind Eng Chem Res 42:2461–2469CrossRefGoogle Scholar
  26. 26.
    Peng Z, Kong LX (2007) Polym Degrad Stab 92:1061–1071CrossRefGoogle Scholar
  27. 27.
    Taghizadeh MT, Yeganeh N, Rezaei M (2015) J Appl Polym Sci 32(25):42117–42129Google Scholar
  28. 28.
    Romero R, Alfano O, Cassano A (1997) Ind Eng Chem Res 36:3094–3109CrossRefGoogle Scholar
  29. 29.
    Sterling J, McCoy B (2001) AIChE J 47:2289–2303CrossRefGoogle Scholar
  30. 30.
    Hulburt H, Katz S (1964) Chem Eng Sci 19:555–574CrossRefGoogle Scholar

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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Chemical EngineeringRyerson UniversityTorontoCanada

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