Laboratory Manual CHEM4005FACULTY OF ENGINEERING - SOHAR UNIVERSITY REACTION ENGINEERING(CHEM4005) Course Coordinator: Dr. Ahmed Jawad Ali Teaching Assistant : Mrs. Saud Mrs. Fatma Abdel Ameer Reaction Engineering CHEM4005 1 Laboratory Manual CHEM4005 FACULTY OF ENGINEERING - SOHAR UNIVERSITY Table of Contents Table of Contents 1. Introduction 2. General Instructions 3. Report Preparation Guidelines 4. Laboratory Safety Rules 5. Experiment 1 6. Experiment 2 7. Experiment 3 8. Experiment 4 BATCH REACTOR CONTINUOUS STIRRED TANK REACTOR STIRRED TANK REACTORS IN SERIES TUBULAR REACTOR Page 3 3 4 7 9 15 22 27 Reaction Engineering CHEM4005 2 Laboratory Manual CHEM4005 FACULTY OF ENGINEERING - SOHAR UNIVERSITY Introduction: This lab is one of the most important labs in the chemical engineering study. In this lab, student will perform experiments to support their theoretical study of Batch, CSTR and PFR reactors. Objectives: 1- To familiarize students with main type of chemical reactors. 2- To analyze the experimental data to obtain the reaction rate expression (reaction order and specific reaction rate constant). 3- Compare results obtained using different concentration measurement techniques. 4- Compare the conversion of reactants during a specification reaction in various types of reactor. 5- Observe batch mixing under different operating conditions. Contents: 4 existing Lab experiments, which are: 1. BATCH REACTOR 2. CONTINUOUS STIRRED TANK REACTOR 3. STIRRED TANK REACTORS IN SERIES 4. TUBULAR REACTOR General Instructions Comments ALL STUDENTS ARE REQUESTED TO ATTEND ALL EXPERIMENTS. One formal repot should be submitted by each group. Final exam will be written exam Grading: • • • Attendance & participation: 10 points Reports: 70 points Exam or presentation: 20 points The above grading guideline is subject to change according to the instructor approach. Reaction Engineering CHEM4005 3 Hand-written reports are accepted.SOHAR UNIVERSITY All students are expected to abide with the following requirements: • • • • • • • • • Respecting all lab safety regulations Reading the experiment handout before performing the experiment.Laboratory Manual CHEM4005 Lab and Report Rules: FACULTY OF ENGINEERING . points will be deducted for unprepared students Delayed reports will not be accepted. Figures should be very well labeled and scaled. typed is preferable. grade will be diminished by 10% daily. however. if accepted under special reasons. Report Preparation Guidelines CHE4005 lab report must contain the following items in the order listed: • • • • • • • • • • Title Summary Objective Theory Procedure Results & discussion Conclusions Literature cited Nomenclature Appendices Reaction Engineering CHEM4005 4 . bad-looking and unorganized reports may be subjected to grade deduction. clear and precise that reflects the work of an Engineer. The text should be written in the past tens or passive voice and avoid using the pronouns I and/or We. The layout and organization of the reports are very important. The results whether in form of tables or figures should be very informative. Reports quality should meet the specification outlined in the report guidelines discussed in the next section. Theory must be pertaining to the experiment in hand. The objective is not necessarily the same as the title. Procedure In this section. The student should use his own wording or at least rephrase the procedure given in the handouts. Numerical values of key results and findings. Theoretical background Theory section should be no less than a page and no more than 3 pages. Objective Objective section should be 2-3 lines paragraph outlining the main objectives of the experiment. Summary Summary section should be no more than one paragraph and it should summarize theMajor results of the experiment. Reaction Engineering CHEM4005 5 . It can include the following items: • • • Introduction to the subject of the specific experiment. the necessary equations and derivations should be presented. the student should list the actual step-by-step used to carry out the experiment.Laboratory Manual CHEM4005 FACULTY OF ENGINEERING .SOHAR UNIVERSITY The following regulations should be taken care of while preparing a report. Brief description of the work done. which define the purpose of each item for the report contents: Title page The title page should be in a separate page and it must consists of the following: • • • • • The name of the experiment The course number The name of students and their ID numbers The date when the experiment was run and the date of submission. In the section. The instructor name. variables and abbreviations used in the report should be given in this section. used in preparing the report and analyzing the results. Any additional data or information should also be attached to the appendix.Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . Literature cited In this section. abnormal or contradictory results and/or of experimental design or procedure deficiencies. Nomenclature An alphabetical list of all symbols. etc. Discussion should contain your engineering analysis of unexpected. Reaction Engineering CHEM4005 6 . Conclusions Conclusion should be no more than paragraph addressing the conclusive results of the experiment. Proper units should be given whenever applicable. calculations. special recommendations may be expressed if any. the student should list all books. etc. analyzed data. Appendices Appendix section can be added to include the raw experimental data. It should also highlight some of the interesting findings or problems encountered.SOHAR UNIVERSITY Results and Discussion The collected data and calculated results can be outlined in the form of neat Tables and Figures for best demonstration. Interpretation of false results or mismatch between theoretical and experimental values can be addressed in this section. References must be arranged alphabetically by author’s name. Journal’s articles. Similarly. Conclusions and recommendation should be written in an itemized format. eating or drinking is not allowed. i. Professor. and Students.e.. Similarly. Students are requested to remain within their experiment vicinity and should not wander around. must abide with the safety rules posted around the labs. These items must not be carried on during experiments.SOHAR UNIVERSITY The laboratory rules apply to everyone using the lab. Technician). students are requested to clean the equipment and its surrounding and return all apparatus to its normal places. in particularly students. • Remove all trash and place it in the receptacle. Reaction Engineering CHEM4005 7 . Report any injuries regardless of its intensity. note books. waste of water. or waste of energy. In case of getting exposed to chemical spill. must be placed in the assigned areas. Turn off the equipment and disconnect the power supply. Report any equipment faults or safety hazards to lab personnel. run to the emergency shower available in the labs. Technicians. Avoid inhalation of gases and vapors of any kind. Avoid unnecessary fluid leakage. • • • • • • • • • • • • • Anyone running an experiment. All personal belongings such as books.Laboratory Manual CHEM4005 Laboratory Safety Rules FACULTY OF ENGINEERING . Students should not manipulate the laboratory equipment or their accessories unless under the supervision of Lab personnel (Instructors.. Mingling with other groups is not recommended. Laboratory Lab coat must be on at all times during experimentation sessions. At the end of the experiment. Teaching assistant.. Protective eye-glasses and gloves must be worn especially when handling chemicals. Smoking is strictly prohibited inside the laboratories. etc. Instructors. Laboratory Manual CHEM4005 FACULTY OF ENGINEERING .SOHAR UNIVERSITY If any emergency arises call on the following numbers EMERGENCY TELEPHONE NUMBERS: Emergency Help: Fire Department: Campus Security: STUDENT NAME : ____________________________ STUDENT ID NUMBER: _______________________ SEMESTER AND YEAR: ____________________ Reaction Engineering CHEM4005 8 . Laboratory Manual CHEM4005 FACULTY OF ENGINEERING .g. DILUTION OF ETHYL ACETATE FOR USE WITH CEB MKII BATCH REACTOR Armfield recommends the use of a 0. for advice. This involves the use of glacial acetic acid and sulphuric acid as well as acetic anhydride.1M) cannot be applied when using Ethyl Acetate. as it can be carried out under safe conditions of temperature and pressure and is well documented. 1M) then further diluting this to the required concentration (e. as well as the effects of varying process conditions such as reaction temperature. Reaction Engineering CHEM4005 9 . Shake the mixture vigorously until the two liquids have mixed. 0. Before carrying out reactions involving any other reagents please refer to Armfield Ltd.1M solution of Ethyl Acetate in the CEB MkII reactor. Although it may be possible to carry out demonstrations using other chemicals. This should be made by diluting concentrated Ethyl Acetate as follows: Therefore add 9.g. Note: The practice of making a strong solution (e. The reaction chosen for the adiabatic demonstration is the hydrolysis of acetic anhydride.SOHAR UNIVERSITY Experiment #1 BATCH REACTOR EXPERIMENTAL PROCEDURES The Armfield batch reactor is designed to demonstrate the mechanism of a chemical reaction in a reactor. Add further water to make up the final volume to 1000 ml. reagent concentrations etc. The required dilution should be made directly as stated above. it is not advisable as the materials of construction of the reactor may not be compatible. The reaction chosen for the isothermal demonstration is the saponification of ethyl acetate by sodium hydroxide.79 ml of concentrated Ethyl Acetate to 900 ml of deionised or distilled water. 1M sodium hydroxide and 0.1M solution of Sodium Hydroxide in the CEB MkII reactor. This may be made by adding 4. IMPORTANT: It is essential when handling these chemicals to wear protective clothing. . To find the reaction rate constant in a stirred batch reactor The reaction:- 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: From the kinetic analysis of a general second order reaction it can be shown that: where k is the reaction rate constant and t is the time of reaction.1M ethyl acetate. EXPERIMENT (A) ISOTHERMAL OPERATION Note: This experiment requires the use of the Armfield Chilled Water Circulator accessory.0g of NaOH to 960ml of deionised water then making up the solution to 1000ml. . gloves and safety spectacles.Laboratory Manual CHEM4005 FACULTY OF ENGINEERING .SOHAR UNIVERSITY DILUTION OF SODIUM HYDROXIDE FOR USE WITH CEB MKII BATCH REACTOR Armfield recommends the use of a 0.5 litre batches of 0. Reaction Engineering CHEM4005 10 .Set up the Chilled Water Circulator as detailed in the CW-16 manual. Using notation from the nomenclature: substituting for X in equation (1) above gives: METHOD Make up 0.Adjust the set point of the temperature controller to 15°C. By recording the conductivity with respect to time. Charge the batch reactor with 0. The conductivity of a sodium hydroxide solution at a given concentration and temperature however. Switch on the chilled water circulator. Carefully add to the reactor 0. Reaction Engineering CHEM4005 11 . 45 minutes.Laboratory Manual CHEM4005 - FACULTY OF ENGINEERING . Both sodium hydroxide and sodium acetate contribute conductance to the reaction solution whilst ethyl acetate and ethyl alcohol do not.5 litres of the sodium hydroxide solution. say. On conclusion of the experiment. The temperature of the sodium hydroxide in the reactor vessel will begin to fall and will be automatically maintained at the desired setpoint (150C in this instance) by the action of the chilled water circulating in the submerged coil. the amount of conversion can be calculated. It has been determined that the degree of conversion of the reagents affects the conductivity of the reactor contents. Ensure use of correct units.0'. It is advisable to set the data collection period to. is not the same as that of a sodium acetate solution at the same molarity and temperature and a relationship has been established allowing conversion to be inferred from conductivity:The calculations are best carried out using a spreadsheet such as Microsoft™ Excel so that the results can be displayed in tabular and graphical form. Now enter the following known constants from the experiment using the Nomenclature list on last page. either manually or using the Armfield Data Logger. As the experiment involves the collection and storage of conductivity data. the data output port in the console must be connected to the Armfield IFD data logger and the computer (as detailed in the instruction leaflet supplied with the interface). the conductivity measurements must now be translated into degree of conversion of the constituents. This will enable data logging of the conductivity at selected time intervals over a selected period. the set of readings of conductivity with time will need to be transferred to the computer as two columns of data. Switch on the reactor agitator and adjust the speed setting to '7. If a computer is not available then the conductivity can be recorded manually at half minute intervals by reading the value directly from the conductivity meter in the console.SOHAR UNIVERSITY - - - Switch the Heat/Chill switch on the CEX console to CHILL.5 litres of the ethyl acetate solution and instigate the data logger program (or begin taking readings if no computer is being used). INTERPRETATION OF RESULTS Having recorded the conductivity of the contents of the reactor over the period of the reaction. Collection of data will be until a stable condition is reached in the reactor and this takes approximately 30 minutes. Ensure the conductivity probe and temperature sensor have both been installed in accordance with the section CONNECTION TO SERVICES. SOHAR UNIVERSITY Reaction Engineering CHEM4005 12 .Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . SOHAR UNIVERSITY Reaction Engineering CHEM4005 13 .Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . Laboratory Manual CHEM4005 5. NOMENCLATURE FACULTY OF ENGINEERING .SOHAR UNIVERSITY Reaction Engineering CHEM4005 14 . Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . The reactor volume can be varied by adjusting the height of the internal standpipe. Calibration of the feed pumps is achieved by pumping water from the reagent tanks to a measuring cylinder over a timed period for a range of pump speeds. The reaction chosen is the saponification of ethyl acetate by sodium hydroxide as it can be carried out under safe conditions of temperature and pressure and is well documented. flowrate (ml/min) can then be drawn. reactor volume. The actual volume must be checked by filling the reactor with water to the overflow then draining the reactor contents into a measuring cylinder.for advice. This will enable data logging of the conductivity at selected time intervals over a selected period of time. If a computer is not available then the conductivity can be recorded manually at half minute intervals by reading the value directly from the conductivity meter in the console. Reaction Engineering CHEM4005 15 . it is not advisable as the materials of construction of the reactor may not be compatible. Before carrying out reactions involving any other reagents please refer to ArmfieldLtd. The data output port in the console must be connected to the Armfield IFD data logger and the computer as detailed in the instruction leaflet supplied with the interface. 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 either manually or by computer. The experiments involve the collection and storage of conductivity data. feed rate etc. A calibration graph for each pump of % speed vs. stirring rate.SOHAR UNIVERSITY Experiment #2 CONTINUOUS STIRRED TANK REACTOR EXPERIMENTAL PROCEDURES The Armfield continuous stirred tank reactor is designed to demonstrate the mechanism of a chemical reaction in this type of reactor as well as the effects of varying the process conditions such as reaction temperature. Although it may be possible to carry out demonstrations using other chemicals. Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . Any small offset in the actual temperature of the reactor contents can be compensated by changing the set point on the controller by a corresponding amount. This may be made by adding 4. 1M) then further diluting this to the required concentration (e. This should be made by diluting concentrated Ethyl Acetate as follows: Therefore add 9.1M solution of Sodium Hydroxide in the CEM MkII reactor. Shake the mixture vigorously until the two liquids have mixed. The required dilution should be made directly as stated above.SOHAR UNIVERSITY DILUTION OF ETHYL ACETATE Armfield recommends the use of a 0.0g of NaOH to 960ml of deionised water then making up the solution to 1000ml. 0.1M) cannot be applied when using Ethyl Acetate. If it is required to operate in batch mode with the temperature elevated above ambient then the temperature sensor should be removed from the gland in the top of the reactor and placed in the vessel on the side of the hot water circulator.g. As the standard reaction is exothermic the heat generated by the reaction will result in a rise in temperature of the vessel contents that is unavoidable. OPERATION AS A BATCH REACTOR If the unit is operated as a batch reactor (no continuous feed to the reactor) then temperature control of the vessel contents will not be possible using the standard arrangement. Note: The practice of making a strong solution (e. preventing overshoot and maintaining the vessel contents at a steady value. If it is required to maintain the reaction at a more precise temperature then it will be necessary to perform the trial at a temperature below the ambient temperature using the optional chilled water circulator CW-16 (not supplied) connected to the coil in the reactor vessel.1M solution of Ethyl Acetate in the CEM MkII reactor.g. EXPERIMENT A To find the reaction rate constant in a Continuous Stirred Tank Reactor THEORY The reaction:Reaction Engineering CHEM4005 16 . DILUTION OF SODIUM HYDROXIDE Armfield recommends the use of a 0. Add further water to make up the final volume to 1000 ml. The temperature controller will then regulate the temperature of the water flowing through the heating coil.79 ml of concentrated Ethyl Acetate to 900 ml of deionised or distilled water. The actual temperature of the vessel contents can be monitored using a spirit filled glass thermometer (not supplied) through the vacant gland in the lid. It is advisable to set the data collection period to.1M) and temperature (20 . is not the same as that of a sodium acetate solution at the same molarity and temperature and a relationship has been established allowing conversion to be inferred from conductivity. say. however.1M sodium hydroxide and 0. It has been determined that the degree of conversion of the reagents affects 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.0. Set the agitator speed controller to 7. Adjust the set point of the temperature controller to 30°C. within the limits of concentration (0 . gloves and safety spectacles. Collection of conductivity data will be until a steady state condition is reached in the reactor and this takes approximately 30 minutes. Refit the lids. 45 minutes. Using the calibration graph for each of the feed pumps. Remove the lids of the reagent vessels and carefully fill with the reagents to a level approximately 50mm from the top.e.0.0 litre batches of 0. volume of reactor and temperature of reaction. Reaction Engineering CHEM4005 17 . second order overall. After a few minutes the temperature sensor tip will be covered (about 25mm of liquid in reactor) – switch on the hot water circulator. Having recorded the conductivity of the contents of the reactor over the period of the reaction. the conductivity measurements must now be translated into degree of conversion of the constituents. INTERPRETATION OF RESULTS. IMPORTANT: It is essential when handling these chemicals to wear protective clothing.1M ethyl acetate. METHOD Make up 5.SOHAR UNIVERSITY can be considered equi-molar and first order with respect to both sodium hydroxide and ethyl acetate.40°C) studied.Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . and instigate the data logger program (or begin taking readings if no computer is being used). flowrate. The calculations are best carried out using a spreadsheet such as EXCEL so that the results can be displayed in tabular and graphical form. The conductivity of a sodium hydroxide solution at a given concentration and temperature. Both sodium hydroxide and sodium acetate contribute conductance to the reaction solution whilst ethyl acetate and ethyl alcohol do not. The steady state conditions will vary depending on concentration of reagents. set the pump speed control to give 40 ml/min flowrate. i. The reaction carried out in a Continuous Stirred Tank Reactor or Tubular Reactor eventually reaches steady state when a certain amount of conversion of the starting reagents has taken place. Switch on both feed pumps and the agitator motor. At this point. Start the spreadsheet program. this data can be transferred onto the spreadsheet. Now enter the following known constants from the experiment using the Nomenclature list on last page. Ensure use of correct units. Reaction Engineering CHEM4005 18 .Laboratory Manual CHEM4005 FACULTY OF ENGINEERING .SOHAR UNIVERSITY On conclusion of the experiment using the Armfield data logger. a set of readings of conductivity with time will be stored in the computer. SOHAR UNIVERSITY Reaction Engineering CHEM4005 19 .Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . Laboratory Manual CHEM4005 FACULTY OF ENGINEERING .SOHAR UNIVERSITY Reaction Engineering CHEM4005 20 . SOHAR UNIVERSITY 5.7 Nomenclature Reaction Engineering CHEM4005 21 .Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . 40°C) studied. volume of reactor and temperature of reaction.0 litre batches of 0. flowrate. It is advisable to set the data collection period to. Set the agitator speed controller to 7. The reaction carried out in a Continuous Stirred Tank Reactor eventually reaches steady state when a certain amount of conversion of the starting reagents has taken place. Collection of conductivity data will be until a steady state condition is reached in the reactor and this takes approximately 45 minutes. say.Laboratory Manual CHEM4005 FACULTY OF ENGINEERING .05M ethyl acetate. The steady state conditions will vary depending on concentration of reagents. Reaction Engineering CHEM4005 22 . Remove the lids of the reagent vessels and carefully fill with the reagents to a level approximately 50mm from the top. 60 minutes. IMPORTANT: It is essential when handling these chemicals to wear protective clothing. gloves and safety spectacles.e. Using the calibration graph for each of the feed pumps.1M) and temperature (20 .05M sodium hydroxide and 0.0. second order overall. within the limits of concentration (0 . METHOD Make up 5.SOHAR UNIVERSITY Experiment 3: STIRRED TANK REACTORS IN SERIES EXPERIMENT E Demonstration of the progress of a second order chemical reaction through three continuous stirred tank reactors connected in series THEORY The reaction:- can be considered equi-molar and first order with respect to both sodium hydroxide and ethyl acetate i. set the pump speed controls to give 60 ml/min flowrate. Refit the lids.0. the conductivity measurements are automatically translated into degree of conversion of the constituents. Comment upon the results obtained. Ensure use of correct units. If readings have been obtained manually then the necessary calculations are best carried out using a spreadsheet such as EXCEL so that the results can be displayed in tabular and graphical form. The conductivity of a sodium hydroxide solution at a given concentration and temperature however. Both sodium hydroxide and sodium acetate contribute conductance to the reaction solution whilst ethyl acetate and ethyl alcohol do not. Reaction Engineering CHEM4005 23 . INTERPRETATION OF RESULTS Having used the Armfield data logger CEX-304IFD to record the conductivity of the contents of the reactors over the period of the reaction. Enter the following known constants from the experiment using the Nomenclature list on page E-6.SOHAR UNIVERSITY Switch on both feed pumps and agitator motor. On conclusion of the experiment the recorded data can be transferred into the spreadsheet. and instigate the data logger program (or begin taking readings if no computer is being used). is not the same as that of a sodium acetate solution at the same molarity and temperature and a relationship has been established allowing conversion to be inferred from conductivity. It has been determined that the degree of conversion of the reagents affects 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.Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . the spreadsheet can be used to calculate values of sodium hydroxide concentration (a1) and sodium acetate concentration (c1) and the degree of conversion (Xa) and (Xc) for each of the samples of conductivity taken over the period of the experiment.SOHAR UNIVERSITY For the values of each of the above.Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . These can be calculated and listed in columns (use spreadsheet COPY facility) alongside the readings of conductivity using the following equations:- Reaction Engineering CHEM4005 24 . Laboratory Manual CHEM4005 FACULTY OF ENGINEERING .SOHAR UNIVERSITY Reaction Engineering CHEM4005 25 . Laboratory Manual CHEM4005 NOMENCLATURE FACULTY OF ENGINEERING .SOHAR UNIVERSITY Reaction Engineering CHEM4005 26 . 79 ml of concentrated Ethyl Acetate to 900 ml of deionised or distilled water. Before carrying out reactions involving any other reagents please refer to ArmfieldLtd.Laboratory Manual CHEM4005 FACULTY OF ENGINEERING .1M solution of Ethyl Acetate in the CET MkII reactor. feed rate etc.for advice. The reaction chosen is the saponification of ethyl acetate by sodium hydroxide as it can be carried out under safe conditions of temperature and pressure and is well documented.g. DILUTION OF SODIUM HYDROXIDE FOR USE WITH CET MKII REACTOR Reaction Engineering CHEM4005 27 . The required dilution should be made directly as stated above. Add further water to make up the final volume to 1000 ml. 1M) then further diluting this to the required concentration (e. Note: The practice of making a strong solution (e. Although it may be possible to carry out demonstrations using other chemicals it is not advisable as the materials of construction of the reactor may not be compatible. Shake the mixture vigorously until the two liquids have mixed. DILUTION OF ETHYL ACETATE FOR USE WITH CET MKII REACTOR Armfield recommends the use of a 0.g. reactant concentration.SOHAR UNIVERSITY Experiment 4 TUBULAR REACTOR EXPERIMENTAL PROCEDURES The Armfield Continuous Tubular Flow Reactor is designed to demonstrate the mechanism of a chemical reaction in such a reactor as well as the effects of varying the process conditions such as reaction temperature. This should be made by diluting concentrated Ethyl Acetate as follows: Therefore add 9. 0.1M) cannot be applied when using Ethyl Acetate. 1M sodium hydroxide and 0. Reaction Engineering CHEM4005 28 . EXPERIMENT A To determine the rate constant using a tubular reactor THEORY can be considered equi-molar and first order with respect to both sodium hydroxide and ethyl acetate i. The steady state conditions will vary depending on concentration of reagents. second order overall.40°C) studied. volume of reactor and temperature of reaction.1M ethyl acetate. The reaction carried out in a Continuous Stirred Tank Reactor or Tubular Reactor eventually reaches steady state when a certain amount of conversion of the starting reagents has taken place.1M) and temperature (20 .SOHAR UNIVERSITY Armfield recommends the use of a 0. flowrate. within the limits of concentration (0 . This may be made by adding 4.Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . METHOD Make up 5.1M solution of Sodium Hydroxide in the CET MkII reactor.0g of NaOH to 960ml of deionised water then making up the solution to 1000ml.e.0.0 litre batches of 0. 45 minutes. gloves and safety spectacles. It is advisable to set the data collection period to. say. set the pump speed controls to give 80 ml/min flowrate for each reactant (Fa = Fb = 80ml/min = 1. Reaction Engineering CHEM4005 29 . Adjust the set point of the temperature controller to 25°C. This will enable data logging of the conductivity at selected time intervals over a selected period.SOHAR UNIVERSITY IMPORTANT: It is essential when handling these chemicals to wear protective clothing. Each reactant passes through pre-heat coils submerged in the water in which they are individually brought up to the reaction temperature. It has been determined that the degree of conversion of the reagents affects 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. by reading the value directly from the conductivity meter in the console.33 x 10-3 dm3/sec. using a suitable hose from a domestic supply through the temperature sensor gland (8) in the lid.) Prior to priming the hot water circulating pump. Ensure the temperature sensor is re-fitted and the gland tightened securely by hand before releasing the outlet tubing. Switch on the hot water circulator. A non-return valve (11) prevents water flowing out of the reactor via the inlet. Using the calibration graph for each of the feed pumps. the data output port in the console must be connected to the Armfield IFD data logger and the computer as detailed in the instruction leaflet supplied with the interface. If a computer is not available then the conductivity can be recorded manually at half minute intervals. it is necessary to pinch together the walls of the tubing connecting the overflow to the hot water circulator. just below the reactor lid. The temperature of the water in the reactor vessel will begin to rise and will be automatically maintained at the desired set-point (250C in this instance). Fill the vessel to a level above the overflow (return to the circulator). At the base of the tubular reactor coil. Refit the lids. As the experiment involves the collection and storage of conductivity data. The reacting solution will emerge from the coil through connector (16) in the lid where a probe senses continuously the conductivity which is related to degree of conversion. Collection of data will be until a steady state condition is reached in the reactor and this takes approximately 30 minutes. fill the reactor with cold water. Prime the pump as detailed in the OPERATIONAL PROCEDURES section of the CEX manual. To fill the vessel. Switch on both feed pumps and instigate the data logger program (or begin taking readings if no computer is being used). Ensure the conductivity probe and temperature sensor have been installed in accordance with the section CONNECTION TO SERVICES. the reactants are mixed together in a "T" connection and begin to pass through the coil.Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . Remove the lids of the reagent vessels and carefully fill with the reagents to a level approximately 50mm from the top. either manually by bending and holding the tube or using a suitable clip (ensuring that any clip used will not cause damage to the tubing). Reactants will flow from both feed vessels and enter the reactor through the connections in the lid. is not the same as that of a sodium acetate solution at the same molarity and temperature and a relationship has been established allowing conversion to be inferred from conductivity:The calculations are best carried out using a spreadsheet such as EXCEL so that the results can be displayed in tabular and graphical form. this data can be transferred onto the spreadsheet. Both sodium hydroxide and sodium acetate contribute conductance to the reaction solution whilst ethyl acetate and ethyl alcohol do not.SOHAR UNIVERSITY INTERPRETATION OF RESULTS The conductivity measurements must now be translated into degree of conversion of the constituents. On conclusion of the experiment using the Armfield data logger. a set of readings of conductivity with time will be stored in the computer. Start the spreadsheet program. Now enter the following known constants from the experiment using the Nomenclature list on page C2. At this point. Reaction Engineering CHEM4005 30 . Ensure use of correct units. The conductivity of a sodium hydroxide solution at a given concentration and temperature however.Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . SOHAR UNIVERSITY Reaction Engineering CHEM4005 31 .Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . Reaction Engineering CHEM4005 32 . When removing the CET reactor from the service unit always drain using the drain valve under the baseplate first. It is further recommended that the experiment be repeated using dissimilar flow rates for the caustic soda and ethyl acetate solutions to investigate the effect that this will have upon the saponification process.SOHAR UNIVERSITY Comment upon the results obtained. The reactor can be left with water in the coil ready for the next experiment.Laboratory Manual CHEM4005 FACULTY OF ENGINEERING . 2. It is recommended that this experiment should be repeated at various other temperatures to investigate the relationship between the specific rate constant (k) and the temperature of reaction. Rinse the feed tanks with demineralised water and pump the water through the reactor to rinse out the chemicals. Notes: 1. NOMENCLATURE FACULTY OF ENGINEERING .Laboratory Manual CHEM4005 6.SOHAR UNIVERSITY Reaction Engineering CHEM4005 33 .