ISSN:
0001-1541
Keywords:
Chemistry
;
Chemical Engineering
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
A frequency domain analysis of reversible molecular diffusion in a granule or relatively stagnant drop of fluid reveals that for the larger values of time the rate equation reduces to \documentclass{article}\pagestyle{empty}\begin{document}$$ \frac{{dW}}{{dt}} = \frac{{15D}}{{R^2}}\left({W^* - W} \right) $$\end{document}Compared with an earlier time domain result \documentclass{article}\pagestyle{empty}\begin{document}$$ \frac{{dW}}{{dt}} = \frac{{\pi ^2 D}}{{R^2}}\left({W^* - W} \right) $$\end{document} the rate predicted is 15/π2 = 1.516 greater and this has been confirmed by results of experiment. An analysis of time constants shows that the dimensionless group relation \documentclass{article}\pagestyle{empty}\begin{document}$$ \frac{{Dt}}{{R^2}} \ge 0.101 $$\end{document} defines mathematically that which is meant by the larger value of time limitation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/aic.690130617
