Chemical Reaction Engineering Lab Manual.pdf PDF

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Summary

Chemical Reaction Engineering Lab (Ch. E-303L) This file includes 1. List of possible hazards in lab 2. Lab Rubrics 3. Equipment / Item Status List 4. List of consumables 5. List of glass wares 6. Equipment Detail manuals 7. Lab Manuals (16 experiments) 8. Lab flexes 9. Material safety data sheets f...

Description

Chemical Reaction Engineering Lab (Ch. E-303L) This file includes 1. List of possible hazards in lab 2. Lab Rubrics 3. Equipment / Item Status List 4. List of consumables 5. List of glass wares 6. Equipment Detail manuals 7. Lab Manuals (16 experiments) 8. Lab flexes 9. Material safety data sheets for chemicals

List of possible hazards in CRE Lab Following are the potential hazards and their remedies S. No.

Potential hazard

Mitigation

Electrical hazard 1

2

3

Circuit breakers are installed with chemical reactor service units to avoid any personnel or equipment damage Chemical hazard 1. Latex gloves and lab coat is 1. Alkali solutions are strongly corrosive recommended to avoid any 2. Acid/alkali solutions are strongly corrosive contact with these chemicals 3. Acid may splash vigorously 2. Slow addition of acid drops in 4. Ethyl acetate is an irritant water is recommended Biological hazard Immediate draining of chemical reactor 1. Retained water in chemical reactor service units service units is recommended may allow the growth of legionella Pneumophila and other water borne microbes Injury from sharp glass objects First aid kit is recommended for lab

4 Fire 5

6

7

CO2 type Fire extinguisher is 1. Ethyl acetate can cause chemical fire (class B recommended fire) 2. Electrical short circuiting (class C fire) Accidental acid or alkali release 1. Immediate evacuation of lab is recommended if release is severe 2. Acid/ alkali must be neutralized with its counterpart 3. Spillage must be confined in affected area only Accidental contact of non-compatible chemicals 1. Ethyl acetate should not be kept near hot plate 2. Acid should not come into contact with pure metals 3. HCl should not be placed with sucrose in lab

The COSHH Regulations The Control of Substances Hazardous to Health Regulations (1988) The COSHH regulations impose a duty on employers to protect employees and others from substances used to work which may be hazardous to health. The regulations require you to make an assessment of all operations which are liable to expose any person to hazardous solids, liquids, dusts, vapors, gases or micro-organisms. You are also required to introduce suitable procedures for handling these substances and keep appropriate records. Since the equipment supplied by Armfield Limited may involve the use of substances which can be hazardous (for example, cleaning fluids used for maintenance or chemicals used for particular demonstrations) it is essential that the laboratory supervisor or some other person in authority is responsible for implementing the COSHH regulations. Part of the above regulations are to ensure that the relevant Health and Safety Data Sheets are available for all hazardous substances used in the laboratory. Any person using a hazardous substance must be informed of the following: Physical data about the substance Any hazard from fire or explosion Any hazard to health Appropriate First Aid treatment. Any hazard from reaction with other substances. How to clean/dispose of spillage. Appropriate protective measures. Appropriate storage and handling. Although these regulations may not be applicable in your country, it is strongly recommended that a similar approach is adopted for the protection of the students operating the equipment. Local regulations must be considered.

Note Book Rubric (10) Excellent (2)

Completion

Timely Response

Comments / Suggestions

Sources of Errors

Organization / presentation of contents

Satisfactory (1)

1. All experiments are written completely and All experiments are results interpreted. written completely 2. Graphs, tables and and results suggestions are interpreted. mentioned Copy is submitted at the end of the Copy is submitted atleast one day semester within before Oral evaluation (viva) given timeline from lab instructor Atleast All All experiments are concluded experiments are with correct interpretation of concluded with results and any discrepancy in correct procedure or equipment is pointed interpretation of out and correction proposed results 1. Sources of error are correctly identified 2. Proper tools e.g. Atleast procedural/ regression analysis is used equipment errors to quantify the are identified magnitudes of errors 3. Effect of errors on results is correctly interpreted 1. A standard format is followed for writing all experiments 2. Index of performing all experiments is available at the start of the notebook Overall neat look is along with the date of maintained performing the experiment 3. Graphs, tables are captioned properly and attached

Unsatisfactory (0)

Experiments incomplete.

are

Submission do not comply with the given time domain

Objective of performing experiment is not clear

Errors are not identified and reasons are unknown

Haphazard presentation lacking any co-ordination between contents

Total Scores

Score

Experiment Performance (40) Excellent (4)

Attendance

100 %

Punctuality

Always on time in 95% labs atleast

Preexperiment activities

Participati on

Post experiment activities

1. Calibration checks of equipment 2. Rinsing and washing of apparatus 3. Clear Procedural understanding 4. Preparation of solutions/ chemicals/ accessories for experiment Active participation in 1. Keeping workplace clean 2. Collection of data 3. Proper handling of equipment / chemicals 4. Cooperating with team members 1. Proper cleaning/washi ng of items 2. Safekeeping of items and accessories 3. Proper Waste disposal of chemical

Good (3)

Satisfactory (2)

Below average (1)

Unsatisfactory (0)

1. Below 1. 75% atleast 1. 90% atleast 1. 80% atleast 75% 2. In case of 2. In case of 2. In case of 2. In case of leaves, lab leaves, lab leaves, lab leaves, lab work is work is work is work is not compensat compensat compensated compensated ed ed Always on time in 90% labs atleast

Always on time in 80% labs atleast

Always on time in 75% labs atleast

On time in less than 75% labs atleast

1. Calibration checks of equipment 2. Rinsing and washing of apparatus 3. Clear Procedural understanding

1. Rinsing and washing of apparatus 2. Clear Procedural understanding

Clear Procedural understanding

No understanding of any experimental activities

Active participation in 1. Keeping Active workplace participation in Active clean 1. Keeping participation in 2. Collection of workplace 1. Collection data clean of data 3. Proper 2. Collection of handling of data equipment / chemicals

1. Proper cleaning/washi ng of items 2. Safekeeping of items and accessories 3. Proper Waste disposal of chemical

1. Proper cleaning/washi ng of items 2. Safekeeping of items and accessories

Proper cleaning/washi ng of items

No active participation in lab activities

No participation in post experiment activities

Scor e

4. Proper shut down of equipment

Safety

Result calculation

Discussion on results

Graph / statistical analysis of data

Analytical thinking

1. All possible hazards are evaluated 2. Proper functioning of safety interlocks is evaluated 3. PPE’s are used properly 4. MSDS are consulted and Lab safety form is filled countersigned by lab instructor 1. Proper data is collected from experiment 2. Erroneous readings/trend s in data are identified 3. All results are calculated 4. Unit consistency is maintained Results are 1. accurate 2. precise 3. reproducible 4. presentable Data/results are presented in 1. graphical form 2. statistically analyzed e.g. trend lines regression coefficients added 3. errors marked graphically 4. graphs properly captioned

1. All possible hazards are evaluated 2. Proper functioning of safety interlocks is evaluated 3. PPE’s are used

1. Proper data is collected from experiment 2. Erroneous readings/trend s in data are identified 3. All results are calculated

Results are 1. accurate 2. precise 3. reproducible

Data/results are presented in 1. graphical form 2. statistically analyzed e.g. trend lines regression coefficients added 3. errors marked graphically

1. All possible hazards are evaluated 2. Proper functioning of safety interlocks is evaluated

All possible hazards are evaluated

No possible hazard evaluation is done

1. Erroneous readings/trend s in data are identified 2. All results are calculated

All results are calculated

No results calculated

Results are 1. accurate 2. precise

Results accurate

are

No idea has been built from data and results

Data/results are presented in 1. graphical form Data/results are No graphical/ 2. statistically presented in statistical analyzed e.g. graphical form manipulation trend lines of data regression coefficients added

1. Objectives of 1. Objectives of 1. Objectives of Objectives of No idea is built experiment are experiment are experiment are experiment are from fully grasped fully grasped fully grasped fully grasped experiment

2. Idea from 2. Idea from 2. Idea from experiment can experiment can experiment can be applied to be applied to be applied to other physical other physical other physical situations situations situations 3. Any 3. Any betterment to betterment to current current procedure is procedure is proposed proposed 4. One has developed theoretical understanding of concept Total Scores

Equipment status in Chemical Reaction Engineering Lab

S. No. 1

2

Equipment

Quantity

Status

Remarks

Chemical Reactor service Unit (CEX MKII) for single Reactors

2

Repairing needed

1. Hot water circulator is malfunctioned 2. Potentiometers for peristaltic pumps and agitator malfunctioning 3. Built-in conductivity probes are damaged and purchased external conductivity meters may not be compatible for online monitoring 4. RCCB at rear of CEX doesn’t work properly 5. Toggle switch for manual/remote positions for peristaltic pumps and agitators malfunctioned

Chemical Reactor service Unit (CEP MK II) for Reactors in series

1

Repairing needed

1. Potentiometers for peristaltic pumps and agitator malfunctioned 2. Toggle switch for manual /remote positions for peristaltic pumps and

Recommendation

agitators malfunctioned 3

Batch Reactor (CEB MKII)

1

Repairing needed

1. Purchased external conductivity meters is not compatible for online measurement (Because of short length, conductivity probe does not properly dips in solution) 2. Connectors for hot water coil damaged 1. Purchased external conductivity meters is not compatible for online measurement 1. Purchased external conductivity meters is not compatible for online measurement

4

Tubular Reactor (CET MKII)

1

5

Continuous stirred tank reactor (CEM MKII)

1

6

Stirred Tank reactors in series

1

Repairing needed

Water bath 6 holes digital

1

Repairing needed

Conductivity meter

3

Quantity not sufficient

1. Built in conductivity probes are heavily scaled and out of order. Purchased external conductivity meters is not compatible for online measurement 1. Temperature overshoots 2. Gasket starts smelling at high temperatures 1 conductivity meter is out of order

7

8

Equipment Details

BATCH REACTOR CEB MK II

Water-Borne Infections The equipment described in this instruction manual involves the use of water which under certain conditions can create a health hazard due to infection by harmful micro-organisms. For example, the microscopic bacterium called Legionella pneumophila will feed on any scale, rust, algae or sludge in water and will breed rapidly if the temperature of water is between 20 and 45°C. Any water containing this bacterium which is sprayed or splashed creating air borne droplets can produce a form of pneumonia called Legionaries Disease which is potentially fatal. Legionella is not the only harmful micro-organism which can infect water but it serves as a useful example of the need for cleanliness. Under the COSHH regulations, the following precautions must be observed. Any water contained within the product must not be allowed to stagnate, i.e. the water must be changed regularly. Any rust, sludge, scale or algae on which micro-organisms can feed must be removed regularly, i.e. the equipment must be cleaned regularly. Where practicable the water should be maintained at a temperature below 20°C or above 45°C. If this is not practicable then the water should be disinfected if it is safe and appropriate to do so. Note that other hazards may exist in the handling of biocides used to disinfect the water. A scheme should be prepared for preventing or controlling the risk incorporating all of the actions listed above. Further details on preventing infection are contained in the publication “The Control of Legionellosis including Legionnaries Disease”- Health and Safety Series booklet HS (G) 70.

INTRODUCTION The Armfield CEB Mk II Batch reactor is specially designed to allow detailed study of this important process. It is one of three reactor types which are interchangeable on the reactor service unit (CEX), the others being CEM Mk II – Continuous stirred tank reactor and CET Mk II-Tubular reactor. It is possible to demonstrate both adiabatic and isothermal reactions due to the excellent insulation properties and the inclusion of an automatic temperature control system. Isothermal reactions can be carried out both below and above ambient temperature. The adiabatic study involves the monitoring of the temperature increase of an exothermic reaction and computer algorithm which relates this to degree of conversion of the reactants.

DESCRIPTION PARTS OF EQUIPMENT

1) Reactor Vessel 2) Base Plate 3) Thumb Nuts 4) Springs 5) Transfer Coil 6) Outer Gland 7) Inner Gland 8) Propeller Agitator 9) Electric Motor 10) Temperature Sensing Probe 11) Inner Gland 12) Conductivity Probe 13) Outer Gland 14) Access Hole

BRIEF DESCRIPTION

The reactor vessel which is in the form of a vacuum insulated flask is set on base plate which is designed to be located on four sports on the service unit and secured by the thumb nuts. The positioning of the reactor on the service unit is illustrated. Springs are used to secure the reactor on the baseplate.

The reactor is equipped with a stainless-steel heat transfer coil to which the hot water circulator of the CEX service unit can be attached. Alternatively, for reaction demonstrations below ambient temperature, chilled water circulator can be connected. The coil is supported by glands in the lid of the reactor.

To assist the heat transfer and also to provide good mixing of the reactants, a propeller agitator driven by an electric motor is also mounted in the lid. The motor speed can be varied from the service unit.

FOR ISOTHERMAL OPERATION (T = To or dT = 0)

In Order to maintain a constant operating temperature within the reactor the coil contains chilled water, the flow of which is automatically adjusted by the temperature controller in the console. The actual temperature is relayed to the controller by sensing probe which is held in the gland in the lid. The controller then opens or closes the solenoid valve in the chilled water circulator to maintain automatically the desired set point. See information on the temperature controller.

During the reaction, the conductivity of the reactants changes as they are converted to products and this conversion is monitored using a conductivity probe.

FOR ADIABATIC OPERATION (dQ = 0)

An efficient vacuum insulation surrounding the reactor allows negligible heat to be removed or added to the system during the course of reaction. This allows the progress of an exothermic reaction to be monitored simply by observing the rise in temperature over a period of time. A temperature probe and transmitted are supplied, the probe being inserted in the gland in the place of the sensor supplied with the CEX service unit. The intention is that the probe then connected to the Armfield Interface Unit (CEX - 90 IFD3) and the software supplied used to monitor the progress of the reaction and diagnose the results.

More information on the use of the interface can be found in the instruction leaflet supplied with it. An access hole in the lid is used as a vent and also as a means of charging the reactor initially with reagents.

When not in use, the reactor can be drained by carefully removing the lid complete with appendages and removing the reactor from the service unit to a suitable waste drain.

CONNECTION TO SERVICES When installed on the service unit, the following connections must be made to make the equipment operable.

ISOTHERMAL OPERATION

Conductivity Probe Place the glass conductivity probe in the reactor through the gland provided. The gland may need to be loosened by hand before the probe can be inserted and can be tightened, again by hand, after insertion. The probe must be inserted until a length of about 40 mm remains protruding from the gland.

Temperature Sensor Place the temperature probe in the reactor through the gland provided in the lid in the same way as the conductivity probe. The probe must be inserted until a length of about 15 mm remains protruding from the gland.

Variable Speed Agitator The contents of the reactor are stirred by a propeller agitator which is driven by an electric motor and gearbox mounted in the lid. The motor is connected to the electrical supply by a jack plug which is plugged into the socket provided on the mains plate of the service unit.

Reaction Temperature As the reaction described in the experiment section is exothermic, the chilled water circulator accessory must be used to operate the batch reactor at temperatures of ambient or less (down to 5o C).

Chilled Water Circulator If it is required to operate the reactor at temperatures below and including ambient it is necessary to provide the reactor at temperatures below and including ambient it is necessary to provide cooling water circulation in the reactor in the place of heating water. In this case the feed and return hoses of the chilled water circulator are connected to the submerged heat transfer coil

in the reactor. The solenoid valve which controls the flow of chilled water to the coil is connected electrically to the CEX control console as described in the CEX manual. See the CW-16 instruction manual for further details.

ADIABATIC OPERATION

The reactor requires no heating, chilling, conductivity or temperature control when used in this mode. The special temperature sensor and transmitter unit supplied with the reactor is installed by insertion into the gland in the lid of the reactor after removing the temperature sensor previously used to maintain the reactor temperature. The transmitter is connected through the interface to a computer so that data logging of the temperature is possible. Refer to the instructional leaflet supplied with the computer interface (CEX-90 IDF3...