UNIVERSITI MALAYSIA PERLIS

Pusat Pengajian Kejuruteraan Bioproses

ERT 316

Problem Based Learning (PBL)

DEADLINE: 2

Group Members:

Please select the question according to the assigned group as labelled in the question

Group 1

1. AFIFAH FADHILAH BINTI ROSLI

2. HEMAVATHI KRISHNAN

3. LOH YIN CHYUAN

4. NORULAKMAL BINTI REZLI

5. NURUL ASYIQIN BINTI ABDUL HALIM

6. SITI KAMILAH BINTI ABDUL RAHMAN

Group 3

1. CHIN LEE ZHEN

2. LAU KOK CHUN

3. MUHAMAD FITRI BIN MOHD ALI

MUSTAWI

4. NUR FARDIHAH BINTI AWANG

5. OW CHOON LIN

6. SYAZWANI BINTI SALEHUDIN

Group 5

1. EE CHEAK THENG

2. LIAO SWEE YUN

3. NG AI PHENG

4. NUR HAZWANI RAWIAH BINTI HASSAN

5. PARAMESWARY A/P SUBRAMANIAM

6. TAN WAN TING

7. WAN NURUL HIDAYAH BINTI WAN

OTHMAN

UNIVERSITI MALAYSIA PERLIS

Pusat Pengajian Kejuruteraan Bioproses

ERT 316: Reaction Engineering

roblem Based Learning (PBL)

DEADLINE: 21 DECEMBER 2012

the question according to the assigned group as labelled in the question

AFIFAH FADHILAH BINTI ROSLI

NURUL ASYIQIN BINTI ABDUL HALIM

SITI KAMILAH BINTI ABDUL RAHMAN

Group 2

1. NG MUI TENG

2. KHAW LING YEE

3. MOGANESWARI A/P ARUMUGAM

4. NUR AMIRAH BINTI AJID

5. NURUL FARHANA BINTI MAT ZAID

6. SITI NOORBANI EREKA BINTI MOHD

ROSLI

MUHAMAD FITRI BIN MOHD ALI

NUR FARDIHAH BINTI AWANG

SYAZWANI BINTI SALEHUDIN

Group 4

1. CHUAY JIE QI

2. LEE LAY PEI

3. NABILAH BINTI MOHD SALLEH

4. NUR FASIHAH BINTI ROSLAN

5. OWI WEI TIENG

6. TAN BOON YEE

NUR HAZWANI RAWIAH BINTI HASSAN

PARAMESWARY A/P SUBRAMANIAM

NURUL HIDAYAH BINTI WAN

Group 6

1. GANESAN A/L KRISHNAN

2. LOH YENG YEW

3. NOOR SHAFIKA BINTI SHAHARUDDIN

4. NURSYAZALINA BINTI IDRIS

5. SHARMILLA A/P MOGAN

6. WAN MUNIRAH BINTI WAN MAT ZIN

7. NAJEEB BIN ABDUL KHALID

the question according to the assigned group as labelled in the questions.

MOGANESWARI A/P ARUMUGAM

NURUL FARHANA BINTI MAT ZAID

SITI NOORBANI EREKA BINTI MOHD

NABILAH BINTI MOHD SALLEH

NUR FASIHAH BINTI ROSLAN

NOOR SHAFIKA BINTI SHAHARUDDIN

NURSYAZALINA BINTI IDRIS

WAN MUNIRAH BINTI WAN MAT ZIN

NAJEEB BIN ABDUL KHALID

QUESTION 1: PRODUCTION OF ACETALDEHYDE (GROUP 1)

Acetaldehyde (systematically ethanal) is a colorless liquid with a pungent, fruity odor. It is

primarily used as a chemical intermediate, principally for the production of acetic acid,

pyridine and pyridine bases, peracetic acid, pentaeythritol, butylene glycol, and chloral.The

production of Acetaldehyde by the catalytic dehydrogenation of ethanol occurs according to

the following formula;

[eq. 1.1]

a) Construct a stoichiometric table for a flow system, identify the reaction phase, hence

calculate the concentration of each species leaving the system, given that the initial flowrate

of ethanol and the conversion of acetaldehyde is 1 kmol/hr and 0.7 respectively.

b) The mechanism of the pyrolysis of acetaldehyde at 520 °C and 0.2 bar is;

By using Pseudo steady state hypothesis (PSSH),derive the rate law for the rate of

dissappearance of acetaldehyde and sketch the reaction pathway for this reaction.

623

233

4333

33

4

3

2

1

2

2

HCCH

HCOCHCHOCHCHO

CHCOCHCHOCHCH

CHOCHCHOCH

k

k

k

k

→•

++•→+•

++•→+•

•+•→

QUESTION 2: PRODUCTION OF ACETONE (GROUP 2)

The reaction to form acetone from isopropyl alcohol is endothermic with a standard heat of

reaction of 62.9kJ/mol. The reaction is kinetically controlled and occurs in the vapor phase

over a catalyst, zinc oxide promoted by zirconium oxide at 350°C & 1 atm.

[eq. 2.1]

a) Construct a stoichiometric table for the above reaction, given that the initial flowrate of

isopropyl alcohol is 800 mol/hr, assuming the flow system is used. Identify the reaction

phase, hence calculate the concentration of each species leaving the reactor if the

conversion of acetone is 0.8.

b) Acetone-butanol-ethanol (ABE) fermentation is to be carried out in chemostat (CSTR)

using an organism such as Clostridium acetobutylicum. To increase the cell concentration

and production rate, most of the cells in the reactor outlet are recycled to the CSTR, such that

the cell concentration in the product stream is 5% of cell concentration in the reactor. Find the

optimum dilution rate that will maximize the rate of lactic acid production in the reactor.How

does this optimum dilution rate change if the exit cell concentration fraction is changed?

Given; Rate of production, rp = (αµ+β) Cc

Where;

QUESTION 3: PRODUCTION OF ETHYLENE OXIDE

Ethylene oxide can be produced by the oxidation of ethylene

reaction in eq.3.1.

The flowsheet of the commercial

consist of two system, a reaction system and a separation system.

Figure

a) Construct a stoichiometric table for the above reaction, taking ethyl

calculation, given that 0.5 lb mol/s of

reactor. Identify the reaction phase and the reaction system, hence calculate the

concentration of each species leaving the reactor

b) When ethylene oxide is heated to about 2

it isomerizes into acetaldehyde

This reaction is carried out isotherm

a first order decay law and is independent of the concentration of both ethylene

acetaldehyde.Derive an equation for conversion as a function of time.

PRODUCTION OF ETHYLENE OXIDE (GROUP 3)

Ethylene oxide can be produced by the oxidation of ethylene (EO) as given in t

[eq. 3.1]

The flowsheet of the commercial production of EO is shown in Figure 3.1. The process

consist of two system, a reaction system and a separation system.

Figure 3.1: Ethylene oxide production

Construct a stoichiometric table for the above reaction, taking ethylene as the basis of

ulation, given that 0.5 lb mol/s of ethylene and 0.25 lb mol/s of oxygen enter the

Identify the reaction phase and the reaction system, hence calculate the

concentration of each species leaving the reactor if the conversion of ethylene oxide is 0.6

is heated to about 200 °C in the presence of a catalyst (

acetaldehyde:

This reaction is carried out isothermically in a batch reactor.The catalyst deactivation follows

a first order decay law and is independent of the concentration of both ethylene

acetaldehyde.Derive an equation for conversion as a function of time.

as given in the chemical

1. The process

ene as the basis of

ethylene and 0.25 lb mol/s of oxygen enter the

Identify the reaction phase and the reaction system, hence calculate the

if the conversion of ethylene oxide is 0.6.

°C in the presence of a catalyst (Al2O3),

ically in a batch reactor.The catalyst deactivation follows

a first order decay law and is independent of the concentration of both ethylene oxide and

QUESTION 4: PRODUCTION OF ETHYLENE GLYCOL

Ethylene glycol is to be produced from a feedstock of 402 million pounds per year of ethane.

The flowsheet for the arrangement of the reactors together with the molar flow rate is shown

in Figure 4.1.

0.4 lb mol/s of ethane is fed to p

reaction mixture is then fed to a separation unit where 0.04 lb/mols of ethane is lost in the

separation process in the ethane and hydrogen streams that exit the separator. 0.3 lb mol/s

enters the packed-bed catalytic reactor toge

oxide. The effluent stream of packed

lb mol/s of ethylene oxide is lost. The ethylene oxide stream is then contacted with water in a

gas absorber to produce 1-lb mol/ft

solution is fed to a continuous stirred tank reactor together with a stream of 0.

to produce ethylene glycol.

Figure

(a) Construct a stoichiometric table for the ethylene glycol reaction. Identify the reaction

phase and the reaction system, hence calculate the concentration of each species

leaving the continuous stirred tank reactor (CSTR).

PRODUCTION OF ETHYLENE GLYCOL (GROUP 4)

thylene glycol is to be produced from a feedstock of 402 million pounds per year of ethane.

The flowsheet for the arrangement of the reactors together with the molar flow rate is shown

hane is fed to plug flow reactor to produce 0.3 lb/mols of ethylene. The

reaction mixture is then fed to a separation unit where 0.04 lb/mols of ethane is lost in the

separation process in the ethane and hydrogen streams that exit the separator. 0.3 lb mol/s

bed catalytic reactor together with oxygen and nitrogen to produce ethylene

oxide. The effluent stream of packed-bed catalytic reactor is passed to a separator where 0.03

lb mol/s of ethylene oxide is lost. The ethylene oxide stream is then contacted with water in a

lb mol/ft3 solution of ethylene oxide in water. The ethylene oxide

solution is fed to a continuous stirred tank reactor together with a stream of 0.4 lb mol/s water

Figure 4.1: Production of ethylene glycol

ct a stoichiometric table for the ethylene glycol reaction. Identify the reaction

phase and the reaction system, hence calculate the concentration of each species

leaving the continuous stirred tank reactor (CSTR).

thylene glycol is to be produced from a feedstock of 402 million pounds per year of ethane.

The flowsheet for the arrangement of the reactors together with the molar flow rate is shown

lb/mols of ethylene. The

reaction mixture is then fed to a separation unit where 0.04 lb/mols of ethane is lost in the

separation process in the ethane and hydrogen streams that exit the separator. 0.3 lb mol/s

ther with oxygen and nitrogen to produce ethylene

bed catalytic reactor is passed to a separator where 0.03

lb mol/s of ethylene oxide is lost. The ethylene oxide stream is then contacted with water in a

solution of ethylene oxide in water. The ethylene oxide

lb mol/s water

ct a stoichiometric table for the ethylene glycol reaction. Identify the reaction

phase and the reaction system, hence calculate the concentration of each species

(b) The rate law for the hydrogenation (H) of ethylene (E) to form ethane (A) over a

cobaIt-molybdenum catalyst is;

Suggest a mechanism and rate limiting step consistent with the rate law.

QUESTION 5: PRODUCTION OF FRENCH FRIES (GROUP 5 & 6)

In your restaurant the french frieas are made by filling a basket with potatoes and dipping

them in hot vegetable fat for 4 minute and then draining them for another 4 minute. Every

hour, the small pieces that fell out of the basket are scooped out because they burn and give a

bad taste. At the end of 16 hour day, the fat is drained and sent out for disposal because at

longer times the oil has decomposed sufficiently to give a bad taste. Approximately 2 pounds

of potatoes are used in 10 gallons of oil.

a) Why is a batch process usually preferred in a restaurant?

b) Design a continuous process to make 1 ton/ day of french fries, keeping exactly the

same conditions as above so they will taste the same. Describe the residence times and

desired flow pattern in solid and liquid phase. Include the oil recycling loop.

c) How might you modify the process to double the production rate from that specified

for the same apparatus?

d) How would you design this continuous process to handle varying load demand?

Note: Creation of a continuous process such as this would eliminate jobs for a million

teenagers!!