• Home
  • Textbooks
  • Separation Process Principles
  • Enhanced Distillation and Supercritical Extraction

Separation Process Principles

J. D. Seader, Ernest J. Henley

Chapter 11

Enhanced Distillation and Supercritical Extraction - all with Video Answers

Educators

Chapter Questions

00:58

Problem 1

For the ternary system, normal hexane-methanol-methyl acetate at $1 \mathrm{~atm}$ find, in suitable references, all the binary and ternary azeotropes, sketch an approximate residue-curve map on a right-triangular diagram, and indicate the distillation boundaries. Determine for each azeotrope and pure component whether it is a stable node, an unstable node, or a saddle.

ES
Eugene Schneider
University of Minnesota - Twin Cities
03:44

Problem 2

For the same ternary system as in Exercise 11.1, use a process-simulation program with the UNIFAC equation to calculate a portion of a residue curve at $1 \mathrm{~atm}$ starting from a bubble-point liquid with a composition of 20 mol\% normal hexane, $60 \mathrm{~mol} \%$ methanol, and $20 \mathrm{~mol} \%$ methyl acetate.

Lottie Adams
Lottie Adams
Numerade Educator
05:34

Problem 3

For the same conditions as Exercise 11.2, use a processsimulation program with the UNIFAC equation to calculate a portion of a distillation curve at $1 \mathrm{~atm}$.

Noah Barguez-Arias
Noah Barguez-Arias
Numerade Educator
01:15

Problem 4

For the ternary system acetone, benzene, and $n$-heptane at 1 atm find, in suitable references, all the binary and ternary azeotropes, and sketch an approximate distillation-curve map on an equilateral-triangle diagram, and indicate the distillation boundaries. Determine for each azeotrope and pure component whether it is a stable node, an unstable node, or a saddle.

David Collins
David Collins
Numerade Educator
03:44

Problem 5

For the same ternary system as in Exercise 11.4, use a process-simulation program with the UNIFAC equation to calculate a portion of a residue curve at $1 \mathrm{~atm}$ starting from a bubblepoint liquid with a composition of $20 \mathrm{~mol} \%$ acetone, $60 \mathrm{~mol} \%$ benzene, and $20 \mathrm{~mol} \%$-heptane.

Lottie Adams
Lottie Adams
Numerade Educator
05:34

Problem 6

For the same conditions as Exercise 11.5, use a processsimulation program with the UNIFAC equation to calculate a portion of a distillation curve at 1 atm.

Noah Barguez-Arias
Noah Barguez-Arias
Numerade Educator
03:08

Problem 7

Develop the feasible product-composition regions for the system of Figure 11.13, using Feed $F_{1}$.

Leon Druch
Leon Druch
Numerade Educator
01:06

Problem 8

Develop the feasible product composition regions for the system of Figure $11.10$ if the feed composition is $50 \mathrm{~mol} \%$ chloroform, $25 \mathrm{~mol} \%$ methanol, and $25 \mathrm{~mol} \%$ acetone.

Vasu Makani
Vasu Makani
Numerade Educator
01:39

Problem 9

Repeat Example 11.3 but with ethanol as the solvent.

Zafar Haider
Zafar Haider
Numerade Educator
01:48

Problem 10

Repeat Example 11.3, but with MEK as the solvent.

Adalynn Griesser
Adalynn Griesser
Numerade Educator
01:48

Problem 11

Repeat Example 11.4, but with toluene as the solvent.

Adalynn Griesser
Adalynn Griesser
Numerade Educator
00:00

Problem 12

An equimolar mixture of $n$-heptane and toluene at $200^{\circ} \mathrm{F}$, $20 \mathrm{psia}$, and a flow rate of $400 \mathrm{lbmol} / \mathrm{h}$ is to be separated by extractive distillation at $20 \mathrm{psia}$, using phenol at $220^{\circ} \mathrm{F}$ as the solvent, at a flow rate of $1200 \mathrm{lbmol} / \mathrm{h}$. Design a suitable two-column system, obtaining reasonable product purities, with only a small loss of solvent.

Jennifer Stoner
Jennifer Stoner
Numerade Educator
View

Problem 13

Repeat Example 11.5, but with a feed of $100 \mathrm{~mol} / \mathrm{s}$ of $55 \mathrm{~mol} \%$ ethanol and $45 \mathrm{~mol} \%$ benzene.

Angela Williamson
Angela Williamson
Numerade Educator
02:27

Problem 14

Determine the feasibility of separating $100 \mathrm{~mol} / \mathrm{s}$ of a mixture of $20 \mathrm{~mol} \%$ ethanol and $80 \mathrm{~mol} \%$ benzene by pressure-swing distillation. If feasible, design such a system.

Nicole Smina
Nicole Smina
Numerade Educator
02:27

Problem 15

Design a pressure-swing distillation system to produce $99.8 \mathrm{~mol} \%$ ethanol for $100 \mathrm{~mol} / \mathrm{s}$ of an aqueous feed containing $30 \mathrm{~mol}$ \% ethanol.

Nicole Smina
Nicole Smina
Numerade Educator
03:18

Problem 16

In Example 11.6, a mixture of benzene and cyclohexane is separated in a separation sequence that begins with homogeneous azeotropic distillation using acetone as the entrainer. Can the same separation be achieved using methanol as the entrainer? If not, why not? [Ref.: Ratliff, R.A., and W.B. Strobel, Petro. Refiner, 33 (5), $151(1954)]$.

Nikhil Choudhary
Nikhil Choudhary
Numerade Educator
02:00

Problem 17

Devise a separation sequence to separate $100 \mathrm{~mol} / \mathrm{s}$ of an equimolar mixture of toluene and 2,5 -dimethylhexane into nearly pure products. Include in the sequence a homogeneous azeotropic distillation column using methanol as the entrainer and determine a feasible design for that column. [Ref.: Benedict, M., and L.C. Rubin, Trans. AIChE, 41, 353-392 (1945)].

James Irizarry
James Irizarry
Numerade Educator
05:07

Problem 18

A mixture of $55 \mathrm{wt} \%$ methyl acetate and $45 \mathrm{wt} \%$ methanol at a flow rate of $16,500 \mathrm{~kg} / \mathrm{h}$ is to be separated into one product of $99.5 \mathrm{wt} \%$ methyl acetate and another product of $99 \mathrm{wt} \%$ methanol. It has been suggested that such a separation might be possible by using a sequence of one homogeneous azeotropic distillation column and one ordinary distillation column. Possible entrainers are $n$-hexane, cyclohexane, and toluene. Determine the feasibility of such a sequence. If feasible, prepare a process design. If not feasible, suggest an alternative process and prove its feasibility.

Ronald Prasad
Ronald Prasad
Numerade Educator
01:47

Problem 19

Design a three-column distillation sequence to separate $150 \mathrm{~mol} / \mathrm{s}$ of an azeotropic mixture of ethanol and water at $1 \mathrm{~atm}$ into nearly pure ethanol and nearly pure water using heterogeneous azeotropic distillation with benzene as the entrainer.

Catherine Lemar
Catherine Lemar
Numerade Educator
06:20

Problem 20

Design a three-column distillation sequence to separate $120 \mathrm{~mol} / \mathrm{s}$ of an azeotropic mixture of isopropanol and water at $\mathrm{I}$ atm into nearly pure isopropanol and nearly pure water using heterogeneous azeotropic distillation with benzene as the entrainer. [Ref.: Pham, H.N., P.J. Ryan, and M.F. Doherty, AlChE J., 35, 1585-1591 (1989)].

Chareen Guzman
Chareen Guzman
Numerade Educator
13:10

Problem 21

Design a two-column distillation sequence to separate $1,000 \mathrm{kmol} / \mathrm{h}$ of $20 \mathrm{~mol} \%$ aqueous acetic acid into nearly pure acetic acid and nearly pure water. The first column should use heterogeneous azeotropic distillation with $n$-propyl acetate as the entrainer.

Jennifer Stoner
Jennifer Stoner
Numerade Educator
01:01

Problem 22

Repeat Example 11.9, with the entire range of methanol feed-stage locations. Compare your results for isobutene conversion with the values shown in Figure 11.39.

Lizabeth Tumminello
Lizabeth Tumminello
Numerade Educator
02:17

Problem 23

Repeat Exercise 11.22, but with activities, instead of mole fractions, in the reaction rate expressions. How do the results differ? Explain.

Anatole Borisov
Anatole Borisov
Numerade Educator
06:17

Problem 24

Repeat Exercise $11.22$, but with the assumption of chemi cal equilibrium on stages where catalyst is employed. How do th results differ from Figure $11.39$ ? Explain.

Kyle Angle
Kyle Angle
Numerade Educator
02:19

Problem 25

Repeat Example $11.10$, but with 10 equilibrium stages instead of 5 . What is the effect of this change?

Steven Swee
Steven Swee
Numerade Educator
01:52

Problem 26

An important application of supercritical extraction is the removal of solutes from particles of porous natural materials. Such applications include the extraction of caffeine from coffee beans and the extraction of ginger oil from ginger root. When $\mathrm{CO}_{2}$ is used as the solvent, the rate of extraction is found to be independent of the flow rate of $\mathrm{CO}_{2}$ past the particles, but dependent upon the particle size. Develop a suitable mathematical model for the rate of extraction that is consistent with these observations. What parameter in the model would have to be determined by experiment?

Anna Miller
Anna Miller
Numerade Educator
01:58

Problem 27

Cygnarowicz and Seider [Biotechnol. Prog., 6, 82-91 (1990)] present a process design for the supercritical extraction of $\beta$-carotene from water with carbon dioxide using the GC-EOS method of Skjold-Jørgensen to estimate phase equilibria. Repeat the calculations for the conditions of their design using the Peng-Robinson EOS with the Wong-Sandler mixing rules. How do the two designs compare?

Manik Pulyani
Manik Pulyani
Numerade Educator
01:58

Problem 28

Cygnarowicz and Seider [Ind. Eng. Chem. Res., 28 , 1497-1503 (1989)] present a process design for the supercritical extraction of acetone from water with carbon dioxide using the GC-EOS method of Skjold-Jørgensen to estimate phase equilibria. Repeat the calculations for the conditions of their design using the Peng-Robinson EOS with the Wong-Sandler mixing rules. How do the two designs compare?

Manik Pulyani
Manik Pulyani
Numerade Educator