Page 115 - Process simulation and control using Aspen

ASPEN PLUS SIMULATION OK REACTOR MODELS 105

2 .5 A feed stream, consisting of di-tert-buty\ peroxide, ethane and acetone, enters a
RYield model at 10 atm and 1250C. The reactor operates at 10 atm and 50oC.
Use the SYSOP0 property method and assume the following component-wise
flow rates in the feed and product streams (see Table 2.3).

TABLE 2.3
Component Feed flow rate (kg/hr) Product flow rate (kg/hr)
di-tert-hntyl peroxide 26.321 1 .949
ethane 0 .301 5 . 314
acetone 0 . 581 19.94

Simulate the RYield reactor and compare the results (mole fractions in the
product) with those obtained for Problem 2.4.
2 .6 As stated in Problem 2.1, the reaction between acetic acid and ethanol gives
ethyl acetate and water.
CH3COOH + C2H5OH (-> CH3COOC2H5 + H20
The inlet stream, consisting of 50 mole% acetic acid, 45 mole% ethanol and
5 mole% water, is fed to a REquil model with a flow rate of 400 kmol/hr at 750C
and 1.1 atm. The reactor operates at 80oC and 1 atm. Using the NRTL property
method, simulate the reactor model and report the compositions of the product
streams.
2 .7 Ethylene is produced by cracking of ethane in a plug flow reactor. The irreversible
elementary vapour-phase reaction is given as:
C2H6 - C2H4 + Hg
ethane ethylene hydrogen
Pure ethane feed is introduced with a flow rate of 750 kmol/hr at 800CC and
5 .5 atm. The reactor is operated isothermally at inlet temperature. The kinetic
data for the LHHW model are given below (Fogler, 2005).
k = 0.072 s"1

£ = 82 x 103 cal/mol
Tq = 1000 K
|C,] basis = Molarity
The reactor length is 3 m and diameter is 0.8 m. Using the SYSOP0
thermodynamic model, simulate the reactor.
2 .8 Repeat the above problem replacing the PFR by a stoichiometric reactor with
80% conversion of ethane. If require, make the necessary assumptions.
2 .9 In acetic anhydride manufacturing, the cracking of acetone occurs and produces
ketene and methane according to the following irreversible vapour-phase reaction:
CH3COCH3 i CHoCO + CH3