Chapter 8: Multiple Reactions

Gas Phase PFR

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POLYMATH report table showing calculated values of differential equation (DEQ) variables. It includes columns for Initial, Minimal, Maximal, and Final values for variables such as Ca, Cb, Cc, Cd, Cto, Fa, Fb, Fc, Fd, Ft, k1a, k2c, reaction rates (r1a, r1b, r1c, r2a, r2c, r2d, ra, rb, rc, rd), Scd, v, V, and y.

List of differential equations: 1) d(Fa)/d(V) = ra, 2) d(Fb)/d(V) = rb, 3) d(Fc)/d(V) = rc, 4) d(Fd)/d(V) = rd.

Explicit equations: 1) Ft = Fa + Fb + Fc + Fd, 2) k1a = 100, 3) Cto = 0.2, 4) y = 1, 5) Cc = Cto*(Fc/Ft)*y, 6) Ca = Cto*(Fa/Ft)*y, 7) Cb = Cto*(Fb/Ft)*y, 8) r1a = -k1a*Ca*Cb^2, 9) r1b = 2*r1a, 10) k2c = 1500, 11) r2c = -k2c*Ca^2*Cc^3, 12) r2a = 2/3*r2c, 13) rb = r1b, 14) r2d = -1/3*r2c, 15) r1c = -r1a, 16) ra = r1a + r2a, 17) rd = r2d, 18) v = 1000, 19) rc = r1c + r2c, 20) Cd = Cto*(Fd/Ft)*y, 21) Scd = if(V > 0.0001) then (Fc/Fd) else (0).

Graph showing gas phase multiple reactions in a plug flow reactor (PFR) with no pressure drop. The x-axis represents reactor volume (V), and the y-axis represents molar flow rates of components Fa, Fb, Fc, and Fd. Fa decreases sharply, Fb peaks and then declines, while Fc and Fd gradually increase.


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