Polychromatic radiation field model for a honeycomb monolith photocatalytic reactor

Md Moazzem Hossain, Gregory Raupp

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

In this paper we extend our radiation field model previously developed to predict the monochromatic light intensity profile inside a photocatalytic square-channeled monolith reactor to predict the integral average polychromatic light intensity profile. In this extended polychromatic formulation, the mathematical representation of the model accounts for a source that emits a distribution of wavelengths and for wavelength-dependent optical properties (reflectivity) of the active photocatalytic thin film coated on the inner walls of the monolith channels. In the sense that these wavelength dependent properties of a given photocatalytic reactor system can be independently measured, the polychromatic radiation field model contains no adjustable parameters. Model predictions for the integral average light intensity transported through square monolith channels of varying length are in excellent quantitative agreement with experimental measurements employing Degussa P25 titania-coated monolith channels and near ultraviolet lamps emitting light primarily in the 300-400 nm range. The model reveals that axial light intensity gradients are severe, with the light intensity in the portion of the monolith channel beyond about 3-4 aspect ratios in length falling to below 1% of the incident light intensity. At a given axial distance down the monolith channel, the effective light flux that reaches the catalytic wall is approximately a factor of two lower than the total light flux through the channel cross section near the channel entrance, and an order of magnitude lower than the total cross section light flux near the channel exit.

Original languageEnglish (US)
Pages (from-to)3027-3034
Number of pages8
JournalChemical Engineering Science
Volume54
Issue number15-16
DOIs
StatePublished - Jul 1999

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Radiation
Fluxes
Wavelength
Ultraviolet lamps
Aspect ratio
Optical properties
Titanium
Thin films

Keywords

  • Indoor air quality
  • Monolith reactor
  • Photocatalytic oxidation
  • Polychromatic radiation
  • Reactor modeling
  • Titania photocatalysts

ASJC Scopus subject areas

  • Chemical Engineering(all)

Cite this

Polychromatic radiation field model for a honeycomb monolith photocatalytic reactor. / Hossain, Md Moazzem; Raupp, Gregory.

In: Chemical Engineering Science, Vol. 54, No. 15-16, 07.1999, p. 3027-3034.

Research output: Contribution to journalArticle

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