Question

B) Consider the series reaction A R S that we studied in lecture, where both reactions are first order and irreversible. A batch reactor is loaded with Cao=4 mol/L and k1=0.25 min!. Plot CA, CR, and Cs as a function of time for a set of different ka's ranging from 0.025 to 2.5 min!. Comment on the dynamics that you observe for the different cases. Which rate constants and operating conditions are optimal if your goal is to maximize the yield of R with respect to A? Note: You do not need to re-derive the equations, just use the ones found in class. Also note that the profiles would be the same for a PFR plotted in terms of space time.

Answer 1

k1	k2	t	CR	CA	CS
0.25	0.025	0	0	4	0
0.25	0.225	5	1.52590682	1.14601919	1.32807399
0.25	0.425	10	0.38754723	0.32833999	3.28411278
0.25	0.625	15	0.06248781	0.09407098	3.84344121
0.25	0.825	20	0.01171805	0.02695179	3.96133016
0.25	1.025	25	0.00249091	0.00772182	3.98978727
0.25	1.225	30	0.00056727	0.00221234	3.9972204
0.25	1.425	35	0.00013486	0.00063385	3.99923129
0.25	1.625	40	3.3018E-05	0.0001816	3.99978538
0.25	1.825	45	8.2586E-06	5.2029E-05	3.99993971
0.25	2.025	50	2.0995E-06	1.4907E-05	3.99998299
0.25	2.225	55	5.4061E-07	4.2708E-06	3.99999519
0.25	2.425	60	1.4064E-07	1.2236E-06	3.99999864
0.25	2.5	65	3.8952E-08	3.5057E-07	3.99999961

CR vs k2 18 16 14 12 1 0.8 0.6 0.4 0.2 0 0 0.5 1 1,5 2.5 3 en

optimum k2 = 0.225 min^-1

45 3.5 3 2.5 CR CA 15 Cs 1 0.5 10 20 40 30 50 60 70 time, min Concentration

C_S=C_Ao-C_A-C_R

ARS CR (e-1k e14d -