Diffusion with a heterogeneous chemical reaction

Input(s)

$\boldsymbol{D}_{\boldsymbol{A} \boldsymbol{B}}$: Diffusivity $\left(\mathrm{ft}^{2} / \mathrm{s}\right)$

$\boldsymbol{\delta}$: Position of Catalytic Film $(\mathrm{cm})$

$\boldsymbol{x}_{\boldsymbol{a}}$: Main Stream Concentration $\left(\mathrm{mol} / \mathrm{ft}^{3}\right)$

c: Total Molar Concentration $\left(\mathrm{mol} / \mathrm{ft}^{3}\right)$

Output(s)

N: Molar Flux (mol/ft $\left.\mathrm{ft}^{2} \mathrm{~s}\right)$

Formula(s)

$$ \mathrm{N}=\left(\frac{2 * \mathrm{c} * \mathrm{D}_{\mathrm{AB}}}{\delta}\right) * \ln \left(\frac{1}{1-0.5 * \mathrm{x}_{\mathrm{a}}}\right) $$

Reference(s)

Bird, R.B., Stewart, W.E. and Lightfoot, E.N. (2002). Transport Phenomena (Second Ed.). John Wiley \& Sons, Chapter: 18, Page: 553.