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. Continuous column extraction 9. GMP 1/210. PID control11. Membrane separation - pervaporation12. Pharmaceutical Plant visit.

IntroductionStudents 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 informationRefer to CRA and MSDSHazard identification and risk assessmentChemical Hazard class Hazard

identification and risks

Risk phrases

Calcium carbonate Xi Xi 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. IntroductionThe integrated form of the filtration equation for constant pressure filtration (assuming an incompressible filter cake) gives:

V 2 + AVL = A 2 Pt 2 v rv

i.e. V = 2A 2 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 cakeVolume 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 rv 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 Procedure2.1 EquipmentAs 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 rv, L, r and L. Compare values. v

Use the rv, 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. ReportThe 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 e values for each filtration. 4.5 The calculated filter-frame area in scale-up.

Note: (i) All calculations and units of measurement are to be clearly shown.(ii) 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.

MethodComplete 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/tolueneFeed composition: 60 mol %toluene/40 mol % benzene (xf = 0.4)Reflux ratio (R): 4Feed temperature: 95oCTheoretical plates: 7 (N)Distillate flow: 3.75 kmol h-1

Feed stage: 4Pressure: 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.ReferenceBuilding and Running a Process Model Version 11.

Modeling of Industrial Chemical Processes – Separation Processes (II)

IntroductionThis 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 benzene2.31 kmol s-1 acetone

MethodComplete 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 extractionUse 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 KP: 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.ReferenceBuilding 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 dXR = (1)

A dtWhere

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………………………………………… oC

Air velocity…………………………………………….. m/s

Surface area…………………………………………….. m2

Time (s) 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 WsX = I

Ws

Ws dXR = II

A dt

whereW = weight of total solid (kg)Ws = weight of dry solid (kg)

References

Geankoplis, Christie, J (1983). Transport Processes and Unit Operations, 2nd ed. Massachusetts, Allyn and Bacon. Inc., pg 508-552

Spray dryingThe 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

wheredw/ 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

Ta = dry bulb air temperature, oCTs = wet bulb air temperature, oCWo = initial moisture content, kg water/kg dry solidWc = critical moisture content at end of constant rate period, kg water/kg dry solid t = constant rate drying time, s

Heat transfer/Heat exchangersThis 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 informationRefer to CRA and MSDS sheetsHazard identification and risk assessmentChemical Hazard class Hazard

identification and risks

Risk phrases

Sodium hydroxide solution

C Causes severe burns R35

Ethyl acetate F, Xi Highly flammable. Irritating to eyes.

R11, 36, 66, 67

Sodium acetate none none noneEthanol F Highly flammable 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 InformationRefer to CRA and MSDS sheets

Hazard identification and risk assessment

Chemical Hazard Class Hazard Identification & Risks

Risk Phrases

Sodium hydroxide solution

C Causes severe burns

R35

Ethyl acetate F, Xi Highly flammable. Irritating to eyes

R11, 36, 66, 67

Sodium acetate None None noneEthanol F Highly flammable 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.

IntroductionAimTo 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 CH3COONa + C2H5OH Sodium Hydroxide Ethyl Acetate 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 + CH3COOC2H5 CH3COONa + C2H5OH

at time= 0 a a 0 0

at time=t a – x a – x x xFrom 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 2.0m3 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 Hazard class

Hazard identification and risks Risk phrases

methanol F, T 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.

R11, 23, 24, 25, 39

isopropanol F, Xi Highly flammable. Irritating to eyes. Vapours may cause drowsiness and diziness.

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 anti-bump 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 cm3CH3OH cm3H2O~0.2 35 65~0.4 60 40~0.6 75 25~0.8 90 10~0.9 95 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).

Results1. 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 experimentsThe 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 sheetsHazard identification and risk assessment

Chemical Hazard

class

Hazard identification and

risks

Risk

phrases

111 - trichloroethane Xn, N Harmful by inhalation. R20, R59

propanoic acid C Causes burns R34

‘Leksol’ (n-propyl

bromide)

Xn Harmful by inhalation R20

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 111-

trichloroethane 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 informationRefer to CRA and MSDSHazard identification and risk assessmentChemical Hazard class Hazard identification

and risksRisk phrases

Ethanol F Highly flammable 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