Hi there.

I am trying to use MATLAB to make a plot of PA vs time for the problem ( see picture #1)

I am able to get a component balance in terms of conversion, but when I integrate and use MATLAB to plot the conversion vs time I get the result = infinity for conversion. I do not know what is going wrong with my code.

I have attached the problem statement, my work on how I arrived at the equations, and my MATLAB code.

I am really really stuck here and would appreciate any help...

The code is here

clear all

clc

k = 1*10^-3;

KA = 10;

W = 0.1;

T = 400;

P = 100;

yA0 = 0.5;

yB0 = 0.5;

NA0 = .5 % Assuming a basis of 1 mol to start

Ptot = 100;

PA0 = 50;

V = 100,000; %cm3

R = 8.314*10^3 %units cm3 kPA K-1mol-1

i = 1; % initial array index

x(i) = 0; % dimensionless, initial conversion

t(i) = 0; % s, initial time

dt = 0.5; % s, step size

trxn = 5000; % s, final time

while t(i) <= trxn

dxdt = W*k*((PA0*(1-x)).^2)/(1+KA*(PA0*(1-x))*(PA0*V/R*T));

x(i+1) = x(i) + dxdt * dt

t(i+1) = t(i) + dt;

i = i+1; % increment array index

end

plot(t,x)

tt = sprintf('Conversion vs. time, X is %4.4f at trxn = %4.2f', max(x),trxn)

title(tt)

ylabel('X'), xlabel('time (s)')

axis([0 ceil(max(t)) 0 1])

max(x)