1. Chemical Reaction Engineering (CRE) is the field that studies the rates and mechanisms of chemical reactions and the design of the reactors in which they take place. Lecture 24 (Ch. 13)

2. Web Lecture 24 Class Lecture 22-Thursday 3/24/2011 Review of Multiple Steady States Blowout Velocity CSTR Explosion Batch Reactor Explosion 2

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5. R(T) T Variation of heat removal line with inlet temperature. Increasing T 0 5

6. R(T) T0T0 TaTa T κ =∞ κ =0 Increase κ Variation of heat removal line with κ ( κ =UA/C P0 F A0) 6

7. Variation of heat generation curve with space-time. 7

8. Finding Multiple Steady States with T 0 varied 8

9. Temperature ignition-extinction curve 9

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13. 13 UA = 73,520 UA = 0

14. Example: PBR A ↔ B 14

15. Example: PBR A ↔ B 15 Exothermic Case: XeXe T KCKC T KCKC T T XeXe ~1 Endothermic Case:

16. Conversion on Temperature Exothermic Δ H is negative Adiabatic Equilibrium temperature (T adia ) and conversion (Xe adia ) X X e adia T adia T 16

17. T X Adiabatic T and X e T0T0 exothermic T X T0T0 endothermic Trends: -Adiabatic: 17

18. 18 T X eadia X

19. Adiabatic: 19 Effect of adding inerts on adiabatic equilibrium conversion X T T0T0 Adiabatic Equilibrium Conversion

20. X2X2 F A0 F A1 F A2 F A3 T0T0 X1X1 X3X3 T0T0 T0T0 Q1Q1 Q2Q2 20

21. X T X3X3 X2X2 X1X1 T0T0 XeXe X EB 21

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25. What happens when we add Inerts, i.e., vary Theta I??? It all depends what you change and what you hold constant!!! 25 \ Effect of Adding Inerts to an Endothermic Adiabatic Reaction

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29. Nomenclature note: Sub I with Inerts I and reactant A fed Sub A with only reactant A fed F TI = Total inlet molar flow rate of inert, I, plus reactant A, F TI = F A0 + F I0 F TA = Total inlet molar flow rate when no Inerts are fed, i.e., F TA = F A0 P I, T I = Inlet temperature and pressure for the case when both Inerts (I) and A are fed P A, T A = Inlet temperature and pressure when only A is fed C A0 = Concentration of A entering when no inerts are presents C TA = Total concentration when no inerts are present C TI = Total concentration when both I and A are present C A0I = Concentration of A entering when inerts A are entering  I = Entering volumetric flow rate with both Inerts (I) and reactant (A) 29

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32. That is the term in brackets, [ ], would be 1 which would keep  0 constant with  I =  A =  0. Returning to our combined mole balance, rate law and stoichiometry 32

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36. For the same temperature and pressures for the cases with and without inerts, i.e., P I = P A and T I = T A, then 36

37. Mole Balance Rate Laws Stoichiometry Isothermal Design Heat Effects 37

38. Mole Balance Rate Laws Stoichiometry Isothermal Design Heat Effects 38

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