MSc
Pharmaceutical and Chemical Process Technology
LABORATORY MANUAL
September 2008
CONTENTS
1.
Filtration at constant pressure.
2.
Aspen Plus tutorials (version 11):
Separation Processes (I and II)
3.
Drying of solids – (i) tray drying
(ii) spray drying
(iii) fluid bed drying
4.
Heat Transfer – double tube and shell and tube heat exchangers.
5.
Reactor experiments: Batch reactor
6.
Distillation: Vapour – liquid equilibrium curve and application.
7.
Fluid flow: Flowmeter demonstration
Energy losses in pipes
8.
9.
10.
11.
12.
Continuous column extraction
GMP 1/2
PID control
Membrane separation - pervaporation
Pharmaceutical Plant visit.
Introduction
Students are required to complete practicals from the list provided.
Ensure that you read through each experiment prior to commencement and discuss with
the laboratory supervisor.
Laboratory reports must be written following the completion of each experiment and
handed into the laboratory supervisor for assessment.
Laboratory reports should be written using the following format:

Title

Introduction (statement of objectives, theory, background)

Experimental methods (a concise account of all experimental methods used including
equipment, materials)

Results (tabulation of results, figures, calculations etc)

Discussion (of results)

Conclusions

References
Reports should be contained in plastic envelopes and folders.
All reports must be written using Microsoft Word/Excel.
Filtration at Constant Pressure
Safety information
Refer to CRA and MSDS
Hazard identification and risk assessment
Chemical
Hazard class
Calcium carbonate
Xi
Hazard
identification and
risks
Xi
Risk phrases
R 37/38, 41
Precautions
 Avoid inhalation of dust
Waste
 Calcium carbonate must be dried and reused.
Spillage
 Clear up and dispose of as non-hazardous waste
1. Introduction
The integrated form of the filtration equation for constant pressure filtration (assuming an
incompressible filter cake) gives:
V2 + AVL = A2 Pt
2
v
rv
i.e.
V = 2A2 Pt - 2AL
r v V
v
(V is linear with t/v)
where
V=
volume of filtrate (m3)
A=
filter area (m2)
r=
specific resistance of filter cake
=
filtrate viscosity (Nsm-2)
v=
Volume of cake
Volume of filtrate
L=
filter cake equivalent thickness to cloth or paper (m)
P =
pressure drop (Nm-2)
t=
filtration time (s)
The terms L and rv are termed the filtration constants and may be determined by
v
obtaining values for V and t, plotting V versus t and
V
obtaining slope and intercept. Having obtained these, the values can be used to scale-up
a filtration. If the viscosity of the filtrate is known and a value for v obtained, then
values for r and L may be obtained also. The viscosity at any temperature may be
obtained by using the attached nomograph.
Another parameter of interest is the fractional porosity of the cake, e, and this may be
obtained from measuring cake volume and calculating particle volume from specific
gravity. In summary, the objective of the experiment is to operate a laboratory scale
filtration at constant pressure, estimate the filtration constants, calculate r, L and use the
filtration constants to carry out a preliminary design for a filter press.
2.
Experimental Procedure
2.1
Equipment
As assembled.
2.2
Method
Make up a suspension of 5%w/w CaCO3 (or CaSO4. 2H2O as available) in water and
place in reservoir. Start the stirrer motor. Start the vacuum pump with stopcock A closed
and using stopcock B obtain a steady pressure reading of between 50 and 60 cm Hg (i.e.
between 67,763 and 78,947 Nm-2) to give a steady filtrate flowrate. Use safety screen
provided. Maintain this pressure at a steady reading. Fill the funnel about half-way, at
the same time opening A fully. Adjust B to obtain a steady pressure reading as before.
Maintain the level in the funnel as constant as possible and take filtrate volume readings
at suitable time intervals i.e. try and include at least five readings for each run. Do not
exceed the capacity of the filtrate vessel. Record final filtrate volume. Repeat the
experiment twice more, for each run changing the P to give sensible filtrate flowrates.
Record P values Dry filter cakes in drying oven to constant weight. Record weight,
diameter and thickness of each filter cake.
Retain filter cakes for further use.
3.
Calculations
3.1
Plot V against t/V for the separate P runs and
calculate
rv, L, r and L. Compare values.
v
Use the rv, and L average values obtained to carry out design calculation in 3.2
v
3.2
Filter Design
A filter press consisting of 12 frames is to be operated on a 15 minute cycle using the
slurry above. It is required that the volume of filtrate processed on each cycle should be
80.0 litres. If the pressure drop across the filter is maintained at 4.0 X 105 Nm-2, what is
the required area of each frame? (Note: A filter frame contains two filtration areas).
4.
Report
The following should be included:
4.1
Comments on control of process, appearance of filter cake etc.
4.2
Tabulation of r v and L results.
v
4.3
r and L values.
4.4
4.5
e values for each filtration.
The calculated filter-frame area in scale-up.
Note: (i)
(ii)
All calculations and units of measurement are to be clearly shown.
S.I. units are to be used throughout.
Modelling of Chemical Processes – Separation Processes (I)
Introduction
This practical is concerned with the use of Aspen Plus as a modeling tool for the
operation of continuous fractional distillation.
Objectives
1.
To obtain operating results for a continuous fractional distillation system.
2.
To perform a sensitivity analysis for a continuous fractional distillation system.
3.
To develop a process flowsheet.
4.
To meet a process design specification.
Method
Complete the tutorials in ‘Building and running a process model version 11’ as follows:
Ch.1 Aspen plus basics (20 min.)
Ch.2 Building and running a process simulation model (50 min.)
Ch. 3 Performing a sensitivity analysis (20 min.)
Ch.4 Meeting process design specifications (20 min.)
Ch.5 Creating a process flow diagram (20 min.)
When the tutorials have been completed build and run a process simulation model using
the following process parameters/system specification:
Feed: 10 kmol h-1 benzene/toluene
Feed composition: 60 mol %toluene/40 mol % benzene (xf = 0.4)
Reflux ratio (R): 4
Feed temperature: 95oC
Theoretical plates: 7 (N)
Distillate flow: 3.75 kmol h-1
Feed stage: 4
Pressure: 1 atm.
Obtain operating results for the above system. Choose ‘Template’/’Metric units’ for your
model. Use the RadFrac unit operation model and the UNIFAC activity coefficient
model or IDEAL model. Obtain operating results for a system with 12 stages instead of
7 (N = 12).
Perform a sensitivity analysis on the above system (variation of xd, distillate composition,
with R)
Develop the process flowsheet as described in the tutorial.
Meet a process design specification (say xd = 0.90).
Save results on disc. Print results and include with your report.
Reference
Building and Running a Process Model Version 11.
Modeling of Industrial Chemical Processes – Separation Processes (II)
Introduction
This practical is concerned with the use of Aspen Plus as a modeling tool for the
operation of liquid-liquid extraction.
Objectives:
To obtain operating results for a liquid-liquid extraction system.
1
3
L2
48 kmol s-1 water
4
2
7.69 kmol s-1 benzene
2.31 kmol s-1 acetone
Method
Complete the tutorials in ‘Building and running a process model version 11’ as follows:
Ch.1 Aspen plus basics (20 min.)
Ch.2 Building and running a process simulation model (50 min.)
Ch.3 Performing a sensitivity analysis (20 min.)
Ch.4 Meeting process design specifications (20 min.)
Ch.5 Creating a process flow diagram (20 min.)
When the tutorials have been completed build and run a process simulation model using
the following process parameters/system specification:
Continuous counter-current liquid – liquid extraction
Use Type-Column and Model-EXTRACT. Use UNIQUAC activity coefficient model.
System specifications.
solvent:
48 kmol s-1 water.
feed:
7.69kmol s-1 benzene/2.31kmol s-1 acetone.
T:
298 K
P:
101325 Pa. (1 atm)
N (stages):
3
Vary N (say N = 2, 4, 5, 6) and examine the effect on the raffinate composition.
Print results.
Reference
Building and Running a Process Model Version 11.
Drying of solids – tray drying
Safety information
Hazard identification and risk assessment
Precautions
 sand is used in this experiment
 oven and contents are hot!
Waste
 Sand must be dried and reused.
Spillage
 Sweep up and dispose of as non-hazardous waste
Oven
 Avoid direct contact with any hot item, use tong to manipulate hot apparatus or
use special gloves.
Objectives
Experimental determination of the rate of drying curve for solid, at constant drying
conditions (constant air flow, temperature and humidity).The experiment is carried out in
a batch dryer and heat is supplied by direct contact with heated air at atmospheric
pressure. The drying oven is operated at three temperatures – 100, 110 and 120 deg. cent.
Important Definitions

Humidity of an air-water vapor mixture (H):
H = Mass of Water (kg)  Mass of Dry Air (kg)

Moisture content of a solid (X):
X = Mass of Water (kg)  Mass of Dry Solid (kg)

Equilibrium Moisture Content of a Solid (Xe): Is the final moisture content of a
solid after being brought into contact with a stream of air (having humidity “H”
and temperature “T”) long enough, for equilibrium to be reached. Is expressed in
the same way as X.

Free Moisture Content of a solid: Is the moisture above the equilibrium moisture
content. Is the only moisture that can be removed by drying under the given
drying conditions.

Critical Moisture Content of a solid (Xc): Is the solid moisture content attained,
during the drying process, when the entire surface of the solid is no longer wetted.
Experimental Determination of the Rate of Drying Curve
The rate of drying “R” is defined as the mass of liquid evaporated by unit time and by
unit of exposed surface area for drying. It can be mathematically expressed by
S
dX
R =   
A
(1)
dt
Where
R = drying rate (kg H2O/sm2)
S = weight of dry solid (kg)
A = exposed surface area for drying (m2)
X = solid moisture content (kg H2O/kg dry solid)
t = time (s)
To experimentally determine the rate of drying for a given material (case study sand), a
sample is placed in a dryer and under constant drying conditions, the loss in weight of
moisture during the drying process is determined at constant time intervals.
With the data obtained from the batch experiment, a plot of the solid moisture content
“X” versus time can be made (Figure 1). From this plot, the rate of drying curve can be
obtained by measuring the slopes of the tangents drawn to the curve, which give the
values of dX/dt at given values of t. The drying rate “R” is calculated for each point using
equation (1). The drying rate curve is obtained by plotting R versus the solid moisture
content “X” as in figure 2.
The plot of the rate of drying curve can presents several shapes but generally the two
major points – constant and falling rate period – are present. At time zero the initial
moisture content of the solid is shown at point A or A’ depending on the solid
temperature. At point B the surface temperature as attained its equilibrium value and the
constant rate period starts. This period continues as long as the water is supplied to the
surface as fast as it evaporates. At point C, the solid critical moisture content “Xc” is
attained. At this point there is no insufficient water on the surface to maintain a
continuous film of water and the first falling rate period starts. The wetted area of the
solid continually decreases until the surface is totally dry at point D. At this point begins
the second falling rate period, that continues until the equilibrium moisture content of the
solid is reached, at point E.
Figure1: solid moisture content “X” versus time for constant drying conditions
Figure2: drying rate “R“ versus solid moisture content “X” for constant drying
conditions
Date : ………/………./
Weight of dry solid …………………………………..
kg
Weight of added water………………………………..
kg
Initial moisture content………………………………..
%
Total sample weight (tray + solid + water)…………….
kg
Air temperature…………………………………………
o
Air velocity……………………………………………..
m/s
Surface area……………………………………………..
m2
Time (s)
C
Weight of solid (kg)
Time
(s)
.
X
(kg H2O/kg dry solid)
.
dX/dt
.
R
(kg/s m2)
Calculations

Plot experimental X versus time t

Plot experimental R versus experimental X
Practical Formulas
W  Ws
X = 
Ws
I
Ws dX
R =   
A
dt
II
where
W = weight of total solid
Ws = weight of dry solid
(kg)
(kg)
References
Geankoplis, Christie, J (1983). Transport Processes and Unit Operations, 2nd ed.
Massachusetts, Allyn and Bacon. Inc., pg 508-552
Spray drying
The aims of this experiment are:
 To investigate the performance of the spray drier
 To investigate parameters that control the spray drying process
 To examine and study spray dried product properties e.g. particle size and shape
See operating manual for experimental details.
Drying of solids – fluid bed drying
Introduction: When a stream of gas is passed upwards through a bed of material at a
certain velocity the bed will first expand, then become suspended and agitated by the gas
stream to form a fluidised bed. This has the appearance of boiling liquid due to the
formation of many small bubbles-the so-called ‘bubbling fluidisation’.
At higher gas velocity, larger bubbles and plugs of material are formed resulting in a
more violent type of fluidisation called slugging or spouting. The optimum operating gas
velocity for bubbling fluidisation lies above the minimum fluidising velocity but below
the velocity of entrainment of the material.
If a bed of wet material is fluidised by a heated air stream, as in the laboratory batch
dryer, the conditions are ideal for drying. The very efficient contact between gas and
solid particles results in heat transfer rate causing evaporation (mass transfer) of moisture
which is carried away with the exit air.
The same principles apply for industrial fluid bed dryers-both batch and continuous
types, therefore the laboratory fluid bed dryer can be used to assess the feasibility of
different materials for large scale fluidised drying.
Operating method:
1- Determine the optimum bed depth
The optimum bed depth is that which can be fluidised at the required temperature by
relative high air velocity. The optimum bed depth will vary appreciably with the
material-an initial bed depth of about 75mm is typical.
1- Remove any excess water from the solid sample by decanting and / or using a
filter pump.
2- Place the sample of material in the tub to an appropriate bed depth. Weigh the tub
alone then with the material.
3- Locating the sealing ring into the groove.
4- Switch on the mains supply and select the drying temperature required (select
three temperatures).
5- Note the wet and dry bulb temperatures of the inlet air to the fan and outlet air
from the fluidised bed.
6- Weigh the tub with material at 2 minutes intervals for about 15 minutes (or as
long as it takes to attain constant weight) recording the wet and dry temperature
before removing the tub for weighing. Then weigh at 5 minutes intervals until
constant weigh is achieved indicating that the equilibrium moisture content has
been reached. Record the drying time and moisture content.
From these results plot drying curves of moisture content vs time and drying rate vs
moisture content.
Calculation of Heat Transfer Coefficient
Heat transfer coefficient could be calculated as follows;
Heat lost by entering gas = heat transferred to solids to vaporise the liquid
Therefore (dw/dt) = -h A (Ta – Ts)log mean .1/L
This equation can be integrated to give
h = (Wo – Wc).L /t.A (Ta – Ts)log mean
where
dw/ dt = constant drying rate,
kg.s -1
L = latent heat of vaporisation,
J.kg -1
H = heat transfer coefficient,
W.m -2. oC-1
A = surface area,
m2
o
Ta = dry bulb air temperature,
C
o
Ts = wet bulb air temperature,
C
Wo = initial moisture content,
kg water/kg dry solid
Wc = critical moisture content at end of constant rate period, kg water/kg dry solid
t = constant rate drying time,
s
Heat transfer/Heat exchangers
This aim of this practical is to examine the performance of a double tube heat exchanger
and a shell and tube heat exchanger. Hot and cold water flow rates, hot water temperature
and mode of operation are varied and comparisons are made between the two types of
heat exchanger.
(see operating manual for details of procedures, observations and calculations)
Reactor experiments
Safety information
Refer to CRA and MSDS sheets
Hazard identification and risk assessment
Chemical
Hazard class
Sodium hydroxide
solution
Ethyl acetate
C
Sodium acetate
Ethanol
none
F
F, Xi
Hazard
identification and
risks
Causes severe burns
Risk phrases
Highly flammable.
Irritating to eyes.
none
Highly flammable
R11, 36, 66, 67
R35
none
R11
Precautions
 Avoid contact with sodium hydroxide solution. Wash with water.
 Avoid contact with ethyl acetate. Wash with water.
 Use sodium hydroxide solution and ethyl acetate solution in sealed containers.
 No ignition sources.
Waste
 Reactor contents may be diluted with water and washed down the laboratory sink
at the end of the experiment.
Spill
 No ignition sources
 Wear appropriate PPE
 For ethyl acetate solution use spill kit
 For sodium hydroxide solution dilute with water and clean up with suitable
absorbent material
Further information: see MSDS’s and chemical risk assessment
Isothermal batch reactor
Safety Information
Refer to CRA and MSDS sheets
Hazard identification and risk assessment
Chemical
Hazard Class
Hazard Identification &
Risks
Risk Phrases
Sodium hydroxide
solution
Ethyl acetate
C
Causes severe burns
R35
F, Xi
R11, 36, 66, 67
Sodium acetate
Ethanol
None
F
Highly flammable.
Irritating to eyes
None
Highly flammable
none
R11
Precautions




Avoid contact with sodium hydroxide solution. Wash with water.
Avoid contact with ethyl acetate. Wash with water.
Use sodium hydroxide solution and ethyl acetate solution in sealed containers.
No ignition sources.
Waste

Reactor contents may be diluted with water and washed down the laboratory sink
at the end of the experiment.
Spill




No ignition sources
Wear appropriate PPE
For ethyl acetate solution use spill kit
For sodium hydroxide solution dilute with water and clean up with suitable
absorbent material
Further information: see MSDS’s and chemical risk assessment.
Introduction
Aim
To find the reaction rate constant in a stirred batch reactor under isothermal operating
conditions
The reaction which takes place in the reactor is the alkaline hydrolysis of ethyl acetate.
The following equation shows this reaction:
NaOH
+
CH3COOC2H5
Sodium Hydroxide
 CH3COONa
Ethyl Acetate
+
C2H5OH
Sodium Acetate
Ethyl Alcohol
This reaction is first order with respect to both sodium hydroxide and ethyl acetate, i.e.
the overall reaction order is second order. This reaction is carried out isothermally in a
batch reactor using equal concentrations and volumes of both reactants.
Assuming that the initial concentrations are equal and that the amount of reagent used up
after time (t) is (x) then the concentrations at time (t) are:
NaOH
at time= 0
a
+ CH3COOC2H5 
CH3COONa
a
0
+
C2H5OH
0
at time=t
a–x
a–x
x
x
From the kinetic analysis of a general second order reaction it can be shown that:
k.t = x / a (a – x )
(1)
Where k is the reaction rate constant and t is the time of reaction. Using notation from the
nomenclature at the end of procedure:
x = ao – a1
Substituting for x in equation (1) above gives:
k.t = (ao – a1 ) / ao . a1
(2)
Hence a plot of (ao – a1 ) / ao . a1 against t gives straight line of gradient (slope) equal to
k.
Both sodium hydroxide and sodium acetate contribute conductance to the reaction
solutions. The conductivity of the reacting solution in the reactor changes with the degree
of conversion and this provides a convenient method for monitoring the progress of the
reaction.
Note: definition of all symbols and units are presented later on page i at the end.
Method
1. Check the actual volume of the reactor, since the reactor volume can be varied.
The reactor volume is now set for 1100 cm3.
2. Set up water circulator if you need to circulate cold or hot water. Adjust the set
point of the temperature controller to 15 oC (or to any other required
temperature(s)). Switch the heat switch on if heating is required. Perform this
experiment at two temperatures (say 15 and 25 oC or other).
3. As the experiment involves the collection and storage of conductivity data, the
data output port in the console must be connected to the CEX-330 IFD (data
logger) interface and the computer as detailed in the instruction leaflet. Ensure
the conductivity probe and temperature sensor have been installed.
4. As the reactor volume is set at 1100 cm3, carefully add to the reactor 550cm3 (or
other volume - see step 1 above) of 0.025M sodium hydroxide solution (or
other concentration) and 550cm3 0.025M ethyl acetate solution (always same
concentration and volume of sodium hydroxide). Cover the reactor with its cover.
Use 0.025M of both reactants.
5. Set the agitator speed controller to 7.0.
6.
For collection of conductivity data, it is advisable to set the data collection period
to, say, 45 minutes.
7. All data and results will be presented on the PC directly by the use of Armfield
soft ware supplied for this unit.
NOTE:
Sometimes either the PC or the Armfield Data Logger CEX-330 IFD in the
laboratory may not be working; in this case you need to measure the
conductivity directly from the reactor service unit in time intervals of say 1
minute. In this case you need to perform the calculations by yourself to find the
value of k by using the relationships presented above.
It has been determined that the degree of conversion of the reagents affect the
conductivity of the reactor contents so that recording the conductivity with respect to
time using the Armfield Data Logger can be used to calculate the amount of conversion.
Interpretation of results
Having used the Armfield Data Logger CEX-303 IFD to record the conductivity of the
contents of the reactor over a period of the reaction, the conductivity measurements must
now be translated into degree of conversion of the constituents.
Both sodium hydroxide and sodium acetate contribute conductance to the reaction
solution whilst ethyl acetate and ethyl alcohol do not. The conductivity of a sodium
Page i
Exercises
1. If a batch reactor capable of processing a 2.0m 3 volume of solution at constant
density is available and the interbatch time is 0.5h, calculate the output of ethanol
per day assuming 24h per day operation using the k value obtained from your
practical work. The concentration of the charge to the reactor is 0.5M for each
reactant and the reaction is allowed to go to 90% completion.
2. Find the conversion that maximizes the output from the reactor and determine
what this is per annum assuming plant availability is 8,000h per annum.
Vapour – liquid equilibrium curve and its application
Safety information
For further information refer to CRA and MSDS sheets
Hazard identification and risk assessment
Chemical
methanol
Hazard
class
F, T
isopropanol F, Xi
Hazard identification and risks
Highly flammable. Toxic by inhalation, in contact
with skin and if swallowed. Toxic: danger of very
serious irreversible effects through inhalation, in
contact with skin and if swallowed.
Highly flammable. Irritating to eyes. Vapours may
cause drowsiness and diziness.
Risk
phrases
R11, 23,
24, 25, 39
R11, 36,
37
Precautions
 Handling of methanol is carried out in the fume cupboard. All glassware, sample
bottles and other containers containing methanol must be sealed.
 No ignition sources
 Handling of isopropanol is carried out in the fume cupboard. All glassware,
sample bottles and other containers containing isopropanol must be sealed.
 Avoid contact of methanol with skin. Use gloves if necessary.
 All glassware contaminated with traces of methanol and isopropanol must be
washed in the fume cupboard.
 Any skin contact with methanol or isopropanol should be washed with water.
Waste
 Methanol and isopropanol waste must be put into the solvent waste container in
the fume cupboard.
Spills
 Use spill kit and appropriate PPE to deal with large spillages.
 Small spillages may be dealt with using gloves and a suitable absorbent material
which must then sealed in a suitable container and disposed of as hazardous
waste.
Further information: see MSDS’s and chemical risk assessment.
Objective
To construct a vapour-liquid equilibrium curve for methanol-water
and use it for a distillation problem.
Procedure
Carry out in a fume cupboard. Make-up a 50% v/v CH3OH/H20
mixture (150cm3).
Place the mixture in a 250cm3 2-necked round-bottomed flask set
up for simple distillation using a heating mantle. Place a few antibump granules in the flask and heat until steady boiling occurs.
Collect ~2cm3 of distillate and place in stoppered sample bottle.
Label sample vapour condensate 1. Take sample ( ~ 2 cm3) of
residual liquid from flask similarly and label liquid 1.
Record still head temperature.
Continue distillation and take 5 more samples of distillate and
liquid in still as before. You should aim to take samples when the
still head temperature is 65, 72, 79, 86, 93, 100 deg cent. Record
stillhead temperature each time. Label samples
condensate/distillate 2 and still liquid 2 etc.
Ensure that samples are taken over the full distillation temperature
range (65oC to 100oC)
Analyse the samples using gas chromatography. Isopropanol can
be used as an internal standard and peak area ratio CH3OH/(CH3)2
CHOH is plotted versus % v/v CH3OH.
Analysis
All samples for GC analysis should be prepared as follows:
1.0cm3 of sample + 1.0cm3 of isopropanol diluted to 10ml with
water in a 10 ml volumetric flask. (1µL injection in duplicate).
Measure peak area ratios (methanol/IPA) and read off % v/v
CH3OH from calibration graph.
A calibration graph of peak area ratio versus % v/v CH3OH should
be obtained by preparing the following standard solutions and
analyzing them as above.
Volumes to be made up are as follows (volumetrically, 100 ml).
mole fraction CH3OH
~0.2
~0.4
~0.6
~0.8
~0.9
cm3CH3OH
35
60
75
90
95
cm3H2O
65
40
25
10
5
Calculate exact mole fraction CH3OH in each case and analyse as
for samples above (1.0cm3 sample + 1.0 cm3 IPA diluted to 10 ml
with water in a 10 ml volumetric flask).
Results
1. Calculate vapour/liquid equilibrium data on a mole fraction CH3OH basis.
2. Draw vapour-liquid equilibrium curve. (x-y curve)(mole fraction methanol)
3. Assuming 40 mol% methanol/H20 is fed to a column with three theoretical
plates above the feed and a required product specification of 95 mol%
CH 3OH, calculate the required reflux ratio.
4. If the bottom product is to contain 80 mol% H20/20mol% methanol, how
many theoretical plates are required below the feed point? Assume liquid feed at
boiling point.
Note: all chromatograms must be submitted with your report.
GC settings (suggested)
INJ/DET
120
Initial
80
Final
80
Prograte
4
Range
102
Attenuation
24
Primary
2 kg cm-2
Carrier gas 1
0
Carrier gas 2
2
Hydrogen 1
0
Hydrogen 2
0.5
Air
0.5
Parameters (Para/enter)
WIDTH
5
DRIFT
0
T.DBL
0
ATTEN.
10
METHOD
2421
SPL.WT.
100
SLOPE
1000
MIN.AREA
1000
STOP.TM
655
SPEED
5
FORMAT
0
IS.WT
1
Fluid flow experiments
The aims of this experiment are: (1) to investigate the performance of various flow
measuring devices and (2) to investigate the flow through a pipe at high and low flow
rates.
(see operating manual for details)
Continuous column extraction (UOP 5)
Safety information
Refer to CRA and MSDS sheets
Hazard identification and risk assessment
Chemical
Hazard
Hazard identification and
Risk
class
risks
phrases
111 - trichloroethane
Xn, N
Harmful by inhalation.
R20, R59
propanoic acid
C
Causes burns
R34
‘Leksol’ (n-propyl
Xn
Harmful by inhalation
R20
bromide)
Precautions

Avoid skin contact with propanoic acid. Wash with water if contact.

111-trichloroethane must only be handled in a fume cupboard. Sample bottles and
other containers must be sealed. No open glassware containing 111trichloroethane must be left in the laboratory.

Avoid contact with Leksol. Do not breathe in vapours. Handle in a fume
cupboard.

Seal all containers containing Leksol.
Waste procedure

All 111-trichloroethane waste must be separated from water (lower layer) and
collected in the 111-trichloroethane waste container in the fume cupboard for
recovery.

Propanoic acid solutions may be diluted with water and washed down a laboratory
sink.

Leksol waste should be collected in a separate waste container, separated from
water and recovered.
Spill procedure

Spills of propanoic acid solutions may be neutralised with soda ash and
diluted with water and wiped up with absorbent paper or cloth. Rubber gloves
must be worn.

Spills of 111-trichloroethane must be dealt with by the laboratory technician
using a spill kit and respiratory protection. The laboratory should be
evacuated. Any solid waste resulting from the spill clean-up procedure must
be put in a sealed container and disposed of as hazardous waste.

Spills of Leksol must be dealt with by the laboratory technician using a spill
kit and respiratory protection. The laboratory should be evacuated. Any solid
waste resulting from the spill clean-up procedure must be put in a sealed
container and disposed of as hazardous waste.
Further information: MSDS’s and chemical risk assessment available in the laboratory.
The aim of this experiment is to investigate the extraction performance of a packed
column under different operating conditions.
See operating manual for details. Consult with laboratory supervisor before commencing
this experiment
GMP 1/2 software (computer room 346)
Students are required to complete the tasks given. Marks are allocated on the basis of
work submitted.
PID control
(see Gavin Duffy for details)
Membrane separation – pervaporation
Safety information
Refer to CRA and MSDS
Hazard identification and risk assessment
Chemical
Hazard class
Ethanol
F
Hazard identification
and risks
Highly flammable
Risk phrases
R11
Precautions
 No ignition sources
 Avoid contact with skin. Wash off with water.
Waste procedures
 Waste ethanol should be put into the solvent waste container in the laboratory
 Ethanol/water mixtures should be diluted with water and washed down the
laboratory sink
Spills
 Large spillages should be dealt with using a spill kit and appropriate PPE
For further information see MSDS
Students are required to separate an ethanol/water mixture by pervaporation using a
specified membrane. Permeate flux and membrane selectivity at indicated temperature,
crossflow rate and feed concentration will be determined.
2 litres of an ethanol/water mixture containing 10 % v/v water is separated by
pervaporation at 80 deg. cent. using a hydrophilic membrane which preferentially
permeates water. The active membrane area is 0.0198 m2 . The arrangement of equipment
is shown in the attached diagram. Samples of feed are taken at regular intervals and the %
v/v water in samples measured by Karl-Fischer analysis. Permeate is collected, weighed
and the flux (kg h-1 m-2) calculated (see Table 5, Fig. 5 & 6 provided for details).
Permeate is analysed by GC (see Table 15 provided for details). Fig. 16 (provided) is a
plot of %v/v water in permeate against %v/v water in feed.
Comment on the experimental results.
Calculate the ethanol (containing 0.2%v/v water) rate (kg m-2 h-1) for this membrane
under the experimental conditions.
Calculate a mass balance for this batch.
Calculate selectivity values and comment on your values. Selectivity in binary
pervaporation can be defined as:
α 2,1 = (100 – w1)p/(w1)p
(100 – w1)f/(w1)f
, where w1 is the weight fraction of ethanol. (density of ethanol is 0.79g cm-3)
Visit to a pharmaceutical plant
A visit to a pharmaceutical plant will take place.
All students are required to attend. Details will be provided.
Each student is required to write up a report on the visit which should include the
following:

Process details ,

reactor operation and other process operations including equipment details
and operating conditions,

simple flowsheet showing sequence of main operations and material
flows,

materials, material handling and material quantitites,

environmental aspects (liquid effluents, emissions to air, hazardous waste,
solid waste etc)

plant support services,

product quality

batch record sheet

etc