Chemical/Polymer Reactor Design-3 Muhammad Zafar Iqbal
Leyes & Othmer studied the formation of butyl acetate in a batch operated reactor at 100 deg C, with sulfuric acid as a homogenous catalyst. The original feed contained 4.97 mole butanol/mole acetic acid, and the catalyst concentration was 0.032% by weight of sulfuric acid. The following rate equation was found to correlate the data when an excess of butanol was used: r A = -K C A 2
Where CA is the conc. Of acetic acid in gm/ml, and r is the rate of reaction in gm/mol.min. For a ratio of butanol to acid of 4.97 and a sulfuric acid conc. Of 0.032% by weight, the reaction velocity constant was:
K = 17.4 cm 3 / mol.min
Densities of the mixtures of acetic acid, butanol and butyl acetate are not known. Reported densities for each of three components at 100 deg C were:
Although the density of the reaction mixture varies with conversion, the excess of butanol reduces the magnitude of the change. Therefore as an approximation, the overall density of the mixture was assumed constant and equal to 0.75 g/cm 3 .
a) Calculate the time required to obtain a conversion of 50 %
Some important & Practical Consideration in Designing a Batch Reactor
Always estimate for shutdown time( cleaning time, refilling or recharging time).
Estimate for maximum production rate
Select the cooling or heating medium as per requirement
Perform energy balance calculations over the reactor and calculate the heat required or generated by the reaction.