Multiple Reactions Assignment Problems 2 to 5
2) The parallel first order reactions A → B, A → C, have activation energies of 8
and 10 kcal /mol., respectively. In a 1 liter batch reactor at 1000C the selectivity
to B is 50% the conversion is 50% in a reaction time of 10 min with CA0 =
1mole/liter. The solvent is water and the reactor can be pressurized as needed
to maintain liquids at any temperature.
(a) What temperature and reactor volume are required to produce 90%
selectivity to B at 90% conversion in a CSTR using a feed of 2 molar A at a flow
rate of 10liters/min.
(b) What temperature and reactor volume are required to produce 90%
selectivity to C at 90% conversion in a CSTR using a feed of 2 molar A at a flow
rate of 10liters/min.
(c) What temperature and reactor volume are required to produce 90%
selectivity to B at 90% conversion in a PFR using a feed of 2 molar A at a flow
rate of 10liters/min.
(d) What temperature and reactor volume are required to produce 90%
selectivity to C at 90% conversion in a PFR using a feed of 2 molar A at a flow
rate of 10liters/min.
3) Reactant A decomposes in an isothermal batch reactor (CAo = 100 ) to
produce wanted R and unwanted S, and the following progressive
concentration readings are recorded:
Additional runs show that adding R or S does not affect the distribution of
products formed and that only A does. Also, it is noted that the total number
of moles of A, R, and S is constant.
(a) Find the φ versus CA curve for this reaction.
With a feed of CAo = 100 and CAf = 10, find CR
(b) from a mixed flow reactor,
(c) from a plug flow reactor,
(d) and (e): Repeat parts (b) and (c) with the modification that CAo = 70.
4) When aqueous A and aqueous B (CA0 = CBo) are brought together they
react in two possible ways:
A + B → R + T, rR = 50 CA mol / m3. h
A + B → S + U, rs = 100 CA mol / m3. h
to give a mixture whose concentration of active components (A, B, R, S,
T, U) is Ctotal = CA0 + CB0 = 60 mol/m3. Find the size of reactor needed
and the R/S ratio produced for 90% conversion of an equimolar feed of
FA0 = FBo = 300 mol/h:
(a) in a mixed flow reactor;
(b) in a plug flow reactor;
5) The Series first order reactions A → B, B → C, have activation energies of 8
and 10 kcal /mol., respectively. In a 1 liter batch reactor at 1000C the selectivity
to B is 50% the conversion is 50% in a reaction time of 10 min with CA0 =
1mole/liter. The solvent is water and the reactor can be pressurized as needed
to maintain liquids at any temperature.
(a) What temperature and reactor volume are required to produce 90%
selectivity to B at 90% conversion in a CSTR using a feed of 2 molar A at a flow
rate of 10liters/min.
(b) What temperature and reactor volume are required to produce 90%
selectivity to C at 90% conversion in a CSTR using a feed of 2 molar A at a flow
rate of 10liters/min.
(c) What temperature and reactor volume are required to produce 90%
selectivity to B at 90% conversion in a PFR using a feed of 2 molar A at a flow
rate of 10liters/min.
(d) What temperature and reactor volume are required to produce 90%
selectivity to C at 90% conversion in a PFR using a feed of 2 molar A at a flow
rate of 10liters/min.