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 10

2. Lecture 10 – Tuesday 2/8/2011 2

3. SelectivityYield Instantaneous S D/U = r D /r U Overall Ŝ D/U = F D /F U 3 Keep C A high and C B low.

4. Semi Batch reactors can be very effective in maximizing selectivity in liquid phase reactions. The reactant that starts in the reactor is always the limiting reactant. 4

5. Semibatch reactors A + B → C + D 5 A B, v 0 Initial V Liquid level and volume increase

6. 6 Mass Balance:

7. 7 1)Mole balances: Species A: [in] – [out] + [gen] = [acc]

8. 8 1)Mole balances: Species B:

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13. Everything is the same as for the irreversible case, except for the rate law: Consider the following reaction: 13

14. Where: At equilibrium, then 14 X e changes with time.

15. Soldium Bicarbonate+Ethylene Chrolohydrin  Ethylen Glycol+NaCl+CO 2  NaCHO 3 + CH 2 OHCH 2 Cl  (CH 2 OH) 2 + NaCl + CO 2  A + B  C + D + CO 2  P6-6 B

16. 16 Semibatch Balance in Terms of Moles A + B  C + D + CO 2

17. 17 Rest of the Polymath Statements Similar to Concentration Program

18. P6-6 Semibatch: Moles, N a, N b, etc.

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22. P6-6 Semibatch: Concentrations C A, C B, C C

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25. Three Forms of the Mole Balance applied to Semi Batch Reactors: 1.Molar Basis 2.Concentration Basis 3.Conversion 25

26. Consider the following elementary reaction: A+B  C+D -r A =kC A C B The combined Mole Balance, Rate Law, and Stoichiometry may be written in terms of number of moles, conversion, and/or concentration: ConversionConcentrationNo. of Moles 26

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28. End of Lecture 10 28