1. Lecture 21 Tuesday 3/25/08 CSTR With Heat Effects Multiple Steady States. Ignition and Extiction Temperatures

2. CSTR with Heat Effects Energy Balance for CSTRs Equation (8-9) (page 476)

3. Energy Balance for CSTRs Equation (8-9) (page 476) Using We obtain after some manipulation (page 593)

5. At Steady State Solving for X Solving for T

6. In general

10. Mole Balance Rate Law Stoichiometry Combine

17. Generating G(T) and R(T) Need to solve for X after combining mole balance rate law and stoichiometry. For a first order irreversible reaction Parameters Then plot G and R as a function of T

18. CSTR Heat Effects F io T a2 T a1 FiFi mcmc V Neglect stirring

19. TCTC T R(T) T0T0 T C =T a T R(T) k k=0 (adiabatic) k=∞

20. G T T R,G X,G @ Steady state, G(T)=R(T) T 0 T C T S T 01 T C1 T S1 T 02 T C2 T S2,T S3 T TSTS T0T0 Ignition temp Extinction temp stable unstable T 01 2 3 4 5 T S3 T S1 T S2