✦ LIBER ✦

Effects of unequal diffusivities on enhancement factors for reversible and irreversible reaction

✍ Scribed by W.J. DeCoursey; R.W. Thring

Publisher: Elsevier Science
Year: 1989
Tongue: English
Weight: 583 KB
Volume: 44
Category: Article
ISSN: 0009-2509
DOI: 10.1016/0009-2509(89)80013-2

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✦ Synopsis

The effects of unequal diffusivities of the reactants on enhancement factors for mass transfer with reversible and irreversible second-order chemical reactions are examined, based on the Danckwerts model of mass transfer. A more accurate explicit approximation is obtained for mass transfer with instantaneous irreversible reactions. A new method of calculating approximate enhancement factors for mass transfer with reversible reactions when diffusivities are unequal is developed. Results from the new method agree with limiting relations for equal diffusivities, for second-order irreversible reactions, for instantaneous reactions, and for pseudo-first-order reactions. Accuracies are probably within about 10% over all practical ranges of the parameters, but further comparisons with numerical solutions and experimental data are required.

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