For an ultrafiltration cell the data in Table $1$ have been collected. The feed solution is

a $150kD$ starch solution at $3\mathrm{.}2\frac{g}{L}$ concentration. The membrane rejects the starch

completely. Determine the membrane resistance, $Rm.$ The mass transfer coefficient is

$4\mathrm{.}2{10}^{-5}\frac{m}{s}.$ Assuming that the decrease in flux with solute present is due to osmotic

pressure effects only and that the osmotic pressure follows the relationship $,=a$

$C_w+$

then, estimate $$ and $$ from the data given. You may assume that $R_{cp}$ and $R_g$ are

negligible.

Table $1.$ Pure water and Solution Flux for Starch Solutions in UF$.$

Given that the diffusivity of the starch is estimated as $1\mathrm{.}2{10}^{-11}\frac{m^2}{s},$ then estimate the

thickness of the concentration polarization boundary layer.