[mazibugs]

You are given the following reaction in which A is a liquid hydrocarbon at standard conditions.

A¬ → B + 3C

It can be modeled as a first order irreversible reaction with a measured
k = 5x10 min-1 at 150 oC and a measured Ea = 85 kJ/mol

Pure A is injected into a reactor at 2.5 mol/min with the reactor operating at a temperature of 227oC.  At this temperature all components are in the gas phase.  The steady state pressure in the reactor is 10 atm.


(a) If the reactor is a CSTR, what reactor volume is required to achieve 90% conversion?

(b) If the reactor is a PFR and the pressure drop is negligible, what reactor volume is required to achieve 90% conversion?

(c) If you had a PFR half the volume you computed in part (b), and then fed its output into a CSTR half the volume you computed in part (a), what would the conversion be? What if you hooked them up the other way round: the half-size CSTR first and the half-size PFR afterwards?

Suppose the reaction is carried out in a batch reactor, by filling it with enough A and heating rapidly to 227 C, so that all of A vaporizes, but before any significant reaction has occurred, the initial pressure in the reactor will be 2.7 atm.

(d) What will the pressure be in the isothermal batch reactor when the reaction has run to 90% conversion?

(e) What would the batch reactor volume have to be if we were to process 3600 moles/day (= 2.5 moles/minute) of A this way? Assume that the batch reactor can be emptied and refilled very rapidly, and that it is not necessary to clean the reactor between batches.

(f) Which reactor (CSTR, PFR, batch) would you recommend be used for this process? Explain briefly.

[eugenedakin]

Hello mazibugs,

Could you please provide your work. I am sure that someone will be able to help you once you work through the questions.

Best wishes,

Eugene