Isothermal Continuous Stirred Tank Reactor (CSTRs) : Example Problems

Try to solve these problems before watching the solutions in the screencasts.

Example Problem 1

The hydrolysis of acetic anhydride to form acetic acid is carried out in a 1250-L CSTR. The feed is 2.5 mol/L acetic anhydride and 50. mol/L of water. The reaction:
(CH3CO)2O + H2O ⇋ 2CH3COOH
is first order in (CH3CO)2O and first order in H2O. At the reactor temperature, the rate constant is 0.075 L/(mol s). The feed flow rate is 15 L/s. What is the conversion of acetic anhydride?

Example Problem 2

The liquid-phase, reversible reaction A + B ⇋ 2C occurs in an isothermal CSTR. The feed contains equimolar amounts of A and B in a solvent, and the conversion of A is measured to be 60.%. The equilibrium conversion of A under the same feed conditions is 80.%. When the volumetric flow rate is increased by 50.%, with the same feed concentrations and reactor temperature, what is the new conversion of A? The forward reaction is first order in A and first order in B, and the reverse reaction is second order in C.