SECTION $2$

QUESTION $5$

leactant A decomposes by three simultaneous reactions to form $B($desired$),x$ and $Y($undesired$)$ in the ollowing reactions:

A $x$

AlongrightarrowB $r_x=K_1=0\mathrm{.}0001mo\frac{l}{d}{m}^3.s$

$($Zero order$)$

A $q,r_B=K_2{C}_A=(0\mathrm{.}0015s^{-1})C_A$

$($First order$)$

$r_Y=K_3{C}_A^2=(0\mathrm{.}008d\frac{m^3}{m}ol.s)C_A^2($Second order$)$

The specific reaction rates are given at $300K$ and the Activation Energies for the reactions $1,2$ and $3$ are $E_1=10,000$Kca$\frac{l}{m}ol,E_2=15,000$Kca$\frac{l}{m}ol$ and $E_3=20,000$Kca$\frac{l}{m}ol$ respectively. How and under what conditions should the reaction be carried out to maximize the selectivity of species B for an entering concentration of species $A$ of $0\mathrm{.}4M$ and a volumetric flow rate of $2\mathrm{.}0d\frac{m^3}{s}?$

$14$ Marks