Page 33 - The engineering of chemical reactions

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epoxy glue
urethane varnish
latex paint
polycarbonate plastics
Your instructor will specify the length of the writeup (<l page each is suggested) and the number
of items required. He or she may suggest additional topics or allow you to choose some that
interest you.

1.4 From the list of wholesale prices from Chemical Marketing Reporter, calculate the value of
the ingredients in a bottle of aspirin or iIbuprofen (whichever bottle you have in your medicine
cabinet). How much per bottle is costs in processing, packaging, distribution, retail markup,
and advertising? Which of these is largest?
1.5 From the list of wholesale prices from Table l-4 calculate the wholesale price differences per
mole of the following processes:
(a) propane to propylene;
(b) ethylene to polyethylene;
(c) cyclohexane to benzene;
(d) ethylbenzene to styrene;
(e) styrene to polystyrene;
(f) propane to acetone.
All costs in a process obviously have to be less than these differences.
1.6 Our ancestors made vinegar by aerobic bacterial fermentation of alcohol, which is derived from
sugar, while it is now made by carbonylation of methanol, which is derived by reaction of
synthesis gas, which is obtained by steam reforming of methane.
(a) Write out these reactions.
(b) Compare the industrial acetic acid price per pound with its price (in dilute water solution)
in the grocery store.
1.7 Our ancestors made alcohol by anaerobic fermentation of sugar, while industrial ethanol is
made by hydration of ethylene, which is obtained by dehydrogenation of ethane.
(a) Write out these reactions.
(b) Compare the industrial price per pound of ethanol with its price (in dilute water solution)
in the grocery store after subtracting taxes.
1.8 Ethane costs $O.O5/lb, and ethylene sells for $0.1 Mb. A typical ethylene plant produces 1 billion
pounds/year.
(a) What are the annual sales?
(b) If we had a perfect process, what must be the cost of producing ethylene if we want a profit
of 10% of sales?
(c) The actual process produces about 0.8 moles of ethylene per mole of ethane fed (the yield
of the process is 80%). What is the cash flow of the process? What must be the cost of
producing ethylene if we want a profit of 10% of sales?

1.9 What are price differences in manufacturing the following chemicals? Use prices in Table l-4
and assume that any 02, Ha, or CO reactants are free and any Ha produced has no value.