a.

1. Find the critical value of KB at which fraction of vacant sites starts to increase with conversion for the initial settings. Repeat for KT. Vary only one parameter at a time.
2. Find the value KB where the curve for (CB⋅SCt) versus conversion X changes from convex to concave and explain why this shape change occurs.
3. Write a set of conclusions for your experiments (i) and (ii).

b.

Wolfram and Python
1. Describe how the partial pressure profiles change as you vary the sliders for α, KT, and k.
2. What if the molar flow rate were reduced by 50%; how would X and p change?
3. After reviewing Generating Ideas and Solutions on the Web site (http://www.umich.edu/~elements/6e/toc/SCPS,3rdEdBook(Ch07).pdf), choose one of the brainstorming techniques (e.g., lateral thinking) to suggest two questions that should be included in this problem.
4. Write two conclusions from your experiments with the sliders in this example. Polymath
5. What catalyst weight would be required for 60% conversion?
6. Which parameter will you vary so that PB = PH2 at the middle of the reactor (i.e., W = 5000 kg).

c.

1. Use Polymath to learn how your answers would change if the following data for run 10 were incorporated in your regression table.
−rE′=0.8 mol/kg-cat⋅s, PE=0.5 atm, PEA=15 atm, PH=2 atm
2. How do the rate laws (e) and (f)
(e)−rE′=kPEPH(1+KAPEA+KEPE)2(f)−rE′=kPHPH1+KAPEA compare with the nonlinear analysis with the other rate laws used to model the data?

d.

Wolfram and Python
1. What is the maximum conversion that can be achieved if there is no catalyst decay?
2. Vary k and kd and describe what you find. Can you explain why there is no effect of catalyst decay on conversion at a high value of k?
3. Vary E and kd and then write a few sentences and three conclusions describing the results of your experiments.
4. Explain why conversion with catalyst decay increases with increasing Ed and decreases with increasing E.
Polymath
5. Vary the ratio of (k/kd) and describe what you find.
6. Repeat this example (i.e., the plotting of X vs. t) for a second-order reaction with (CA0 = 1 mol/dm³) and first-order decay, and describe the differences from the base case.

7. Repeat this example for a first-order reaction and first-order decay and describe the differences from the base case.
8. Repeat this example for a second-order reaction (CA0 = 1 mol/dm³) and a second-order decay and describe the differences from the base case.

e.

Wolfram and Python
1. Suppose k_d and US are at their maximum values. What could you do to increase conversion?
2. Vary the parameters and write a set of conclusions. Polymath
3. Use Polymath to learn what the conversion would be if there is no catalyst decay.
4. What if the solids and reactants entered from opposite ends of the reactor? How would your answers change?
5. What if the decay in the moving bed were second order? By how much must the catalyst charge, US, be increased to obtain the same conversion?
6. What if ε = 2 (e.g., A → 3B) instead of zero. How would the results be affected?

f.

Wolfram and Python
1. What happens to a and X when T is varied?
2. What happens to a and X when U₀ is varied?
3. Vary the parameters and write a set of conclusions. Polymath
4. What if you varied the parameters P_A0, Ug, A, and k′ in the STTR? What parameter has the greatest effect on either increasing or decreasing the conversion?
5. Ask questions such as: What is the effect of varying the ratio of k to Ug or of k to A on the conversion? Make a plot of conversion versus distance as Ug is
varied between 0.5 and 50 m/s.
6. Sketch the activity and conversion profiles for Ug = 0.025, 0.25, 2.5, and 25 m/s.
7. What gas velocity do you suggest operating at?
8. What is the corresponding entering volumetric flow rate?
9. What concerns do you have operating at the velocity you selected? Would you like to choose another velocity? If so, what is it? Which parameter will you vary so that conversion increases but activity decreases? Explain, if you can, this unusual behavior.