CHE 350
Homework 8
Due March 21, 2012
1. Prior to the production of polyethylene, acetylene contamination in the gaseous ethylene feed
stream is removed by absorption with DMF in a trayed tower at 15.6 C and 3 atm. The vapor
feed contains an acetylene mol
1
CHE 350 Homework 4
Consider a system consisting of the following components at 320 K and 30 kPa (30 000 Pa):
K-values
propane
40.0402
n-butane
13.5250
i-butane
18.0471
n-pentane
4.5850
i-pentane
5.8564
n-hexane
1.5881
All K-values are greater than 1. Th
CHE 350
Homework Set 3
Due: Feb 8, 2013
1. Consider the following T-x-y data for a benzene-ethanol system at 1 atm:
Temperature ( C)
78.4
77.5
75
72.5
70
68.5
67.7
68.5
72.5
75
Mole % benzene in vapor phase
0
7.5
28
42
54
60
68
73
82
89
Mole % benzene in
1. a. First plot the equilibrium data and the 450-
line. We will look at component A. The distillate
composition of A is 90%, so xD is 0.9. The rectifying section operating line (R.S. O.L.) must cross the 450-
line a
CHE 350
Homework 8
Due March 29, 2013
1. A mixture of components A and B is separated in a trayed tower distillation column. A is the
more volatile component. In a start-up test, the column is run with a saturated liquid feed that
contains 40 mol% A. As t
CHE 350
Homework 7
Due March 15, 2013
1. Prior to the production of polyethylene, acetylene contamination in the gaseous ethylene feed
stream is removed by absorption with DMF in a trayed tower at 15.6 C and 3 atm. The vapor
feed contains an acetylene mol
CHE 350
Homework 6
Solutions
See the attached spreadsheet for the calculations necessary to generate the X/Y plot.
a.
The entering gas has 15 mol% acetone, so, on a solute free basis, YN+1 = 15/85 = 0.176.
90% of the acetone is absorbed, so .9 * 15 = 13.5
First, we draw the diagram from the data given in the problem statement (dark blue dome). Here A is
acetone, C is water and S is solvent. We also draw in the tie-
lines (green).
a. The minimum solvent
CHE 350/ 2013/ HW Set 1
1) A) The liquid product flow rate is 1.5 times the vapor product flow rate:
L=1.5V
A material balance tells us that:
F=L+V
V=F-L
L=1.5F-1.5L
F=100 kmol/h
L+1.5L=150 kmol/h
L=150/2.5=60 kmol/h
V=40 kmol/h
Input enthalpy:
100,000 mo
1. Assume constant molar overflow.
The feed is a saturated liquid, meaning that the q-
line has an infinite slope, or is a vertical line at the
feed composition zF = 0.5.
The slope of the rectifying section oper
CHE 350
Homework Set 2
Solutions
1. a.
For a constant relative volatility, eqn. 4-8 applies:
! =
!,! !
1 + ! (!,! 1)
Plotting this over a range of x,y values for ! = 3.5, we get:
n"pentane'mole'fraction'in'the'vapor'phase'(y)'
1"
0.9"
0.8"
0.7"
0.6"
0.5"
CHE 350
Homework 5
Solutions
See the attached spreadsheet for the calculations necessary to generate the X/Y plot.
a.
The entering gas has 15 mol% acetone, so, on a solute free basis, Y = 15/85 = 0.176. 90%
of the acetone is absorbed, so .9 * 15 = 13.5; 1
Programming bubble point calculations
Assigned 2/7/14
Due 2/28/14
Consider a liquid stream of hydrocarbons with the following flow rates, in kmol/h:
propane:
n-butane:
i-butane:
n-pentane:
i-pentane:
n-hexane:
5.21
6.18
variable
8.96
4.30
3.11
Write a pro
CHE 350
Homework Set 3
Due: Feb 4, 2015
1. Consider the following T-x-y data for a benzene-ethanol system at 1 atm:
Temperature ( C)
78.4
77.5
75
72.5
70
68.5
67.7
68.5
72.5
75
Mole % benzene in vapor phase
0
7.5
28
42
54
60
68
73
82
89
Mole % benzene in
CHE 350
Exam 2
April 13, 2014
1. Consider a trayed tower distilling a binary mixture of n-butane and i-pentane. The equilibrium
curve for this process are provided on the next page of this exam. The feed enters the column
as a saturated liquid at a flow r
CHE 350
Homework 11
Due May 1, 2015
A water-acetone mixture (45 wt% acetone in the feed) is purified by liquid-liquid extraction in a
multistage system with a 1,1,2-trichloroethane solvent to produce a water-acetone raffinate that
contains only 10 wt% ace
CHE 350
Project 1
Aihan Yang 4575908875
This project has two parts. The first part is to calculate the results of an
isothermal flash and find the flow rates and the compositions of
product streams at the tem
CHE 350
Homework 8
Due March 26, 2014
1.
Consider a binary distillation of n-butane and i-pentane. The equilibrium x-y data for the
light key (n-butane) at distillation conditions is given on the next page. The feed is an
equilibrium mixture of equimolar
a.
Find the M point by finding where the feed compositions intersect. Draw a tie line through this point.
The two ends give youre the raffinate and extract points. Get the composition from the graph:
R: 85% A, 8%
CHE 350
Homework 10
Due April 12, 2013
A binary mixture of acetone and isopropanol (50 mol% of each) is distilled to a distillate
at 80 mol% acetone and a bottoms at 25 mol% acetone. The feed is a saturated liquid, the
reflux ratio is 0.5, and the column
CHE 350
Homework 7
Due Feb. 29, 2012
1. A stream of air containing 15 mol% acetone is contacted with water in a perforated tray
column. 90% of the acetone entering with the air is to be absorbed. The entering absorbent
stream is pure water. The column is
CHE 350
Homework 4
Solutions
1. Using pr.m to calculate fugacity coefficient values at 320 K and 30 kPa, we get the following
results:
Component
propane
n-butane
i-butane
n-pentane
i-pentane
n-hexane
!L
39.86
13.43
17.93
4.538
5.801
1.565
!V
0.9960
0.9933