Lab Report CSTR 40L

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TABLE OF CONTENT 1.0TABLE OF CONTENT 2.0 ABSTRACT 3.0 INTRODUCTION 4.0 AIMS/ OBJECTIVE 5.0 THEORY 6.0 APPARATUS 7.0 PROCEDURES 8.0 RESULTS 9.0 CALCULATION 10.0 DISCUSSION 11.0 CONCLUSION 12.0 RECOMMENDATIONS 13.0 REFERENCES

PAGE 2 3 4 5 5-7 8 9-11 12-13 14-23 24-25 25 25 226

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2.0 ABSTRACT In this experiment, we are using CSTR (model: BP143) is designed for experiment on chemical reaction in liquid phase which have isothermal and adiabatic conditions. This model of CSTR used consists of two tanks of solution (feed) and one reactor. More than that, it also has jacketed reaction fitted in the agitated and condenser in this model complete with vessels for raw materials and products, feed pump and thermostat. From this experiment, saponification between sodium hydroxide and ethyl acetate can produce sodium acetate in a batch and the CSTR will evaluate the rate data needed to design a bigger batch which is an industrial scale. To simplify this experiment, two solution sodium hydroxide (NaOH) and ethyl acetate Et(Ac) was put into its own feed tank and then reacted with each other in the CSTR. The product is then analysed by the titrating the sample produce with 0.1 M sodium hydroxide to determine how well the reaction go. Hence, the experiment was conducted and the results shows that the significant value of conversion between sodium hydroxide and ethyl acetate increases almost linearly with the increasing of residence of time. Further details of this experiment can be obtained in the results and discussion section.

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3.0 INTRODUCTION Continuous Stirrer-Tank Reactor (CSTR) usually runs under steady state condition with continuous flow of reactant from the feed tank into the reactor to mix the reactant and form a product. The inlet and outlet has the same significant value of composition as in the reactor. The inlet and outlet streams rate inside of the reactor must be more reachable than any other reactors. The inlet streams will bring all the reactants in at a particular rate and this stream will flow into a large container where there is a shaft with a stirrer attached in the reactor that rotates around continuously to mix the reactants. Hence, there is an outlet stream, which will let the solution to exit from the reactor. This CSTR (model: BP143) does not require much work to keep it running and due to its simplicity of the components involved in the reactor, the maintenance is easy and cheap. However, this reactor takes more space to mix the component compare to other reactor. In reactor design, we have the exact size and type of reactor as well as the method of operation that suitable for a given job. This may required the conditions in the reactor vary with the position and time. In industrial sector, this model BP:143 of CSTR is used when relatively small amount of material are to be treated and this can be calculated with a proper integration of the rate of equation for the operation. However, this may cause some difficulties due to the temperature and composition of the reacting fluid may varies from one point to another within the reactor. This depends on the endothermic or exothermic nature of the reaction where the rate of heat addition or removal from the system and the flow pattern of the fluid through the vessel. This can briefly indicates the particular features and the main areas of application of these reactor types.

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4.0AIM & OBJECTIVES The main purpose of conducting the experiment is:  To carry out saponification reaction between Sodium Hydroxide (NaOH) and Ethyl Acetate Et(Ac) by using continuous Stirred Tank Reactor (CSTR).  To determine the effect of residence time to the reactions extent of conversion.  To evaluate the reaction rate constant.

5.0THEORY 5.1 Reaction Rate The rate of reaction for a reactant and products in particular reactions can be defined as how long the reaction takes place. Considering the distinctive chemical reaction as aA+ bB →cC +dD

EQ 5.0

Where: (a, b, c, d): stoichiometric coefficient of the species (A, B): reactants (C, D): products The reaction rate, r for a chemical reaction occurring in a closed system under constant-volume conditions can be defined as r=

−1 d [ A ] −1 d [B ] 1 d [C ] 1 d [D] = = = EQ 5.0 .1 a dt b dt c dt d dt

Negative notation are used to denotes reactants as seen with the species A and B above and Positive notation are used to denotes product form as seen with the species C and D. The rate of reaction can be also be related to: −rA −rB rC rD = = = EQ 5.0 .2 a b c d

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5.2 Conversion For EQ 5.0 can be rearranged for convenience. A way to do rearranged the equation is to put the quantities on a “Per mole A” as basis as the following equation, b c d A + B → C+ D a a a As the species A becomes the basis calculation, the progression of reaction can be evaluate by observing quantity of moles of products that being formed for every mole of ‘A’ consumed and this can be called as Conversion. The conversion is number of moles ‘A’ that has reacted divided by Number of moles of ‘A’ originally exists at the beginning of the experiment such as: X A=

moles of A reacted moles of A fed

5.3 Continuous Stirred Tank Reactors (CSTR) Generally CSTR with continuous flow or reactants and products runs at steady state. The feed is assumed as a uniform composition throughout the reactor and the exit stream has the same composition as in the tank. When the CSTR is operated at steady state, the rate of reaction with respect to A as the following, dN A =0 dt v

∫ r A dV =V r A 0

F A 0−F A +V rA =0

V=

F A 0−F A −r A

Conversion increases with time as the reactant in feed decreases and product in reactor increases. Time will usually increase as the volume of reactor increases for a continuous flow 6

system. So the conversion X is a function of the volume of reactor. Molar flow rate of species A can be noted by FA0 is fed to the system operated at steady state while the molar flow rate of when species A is reacting within the whole system will be noted as (X*FA0). Molar flow rate of A to the system minus the reaction of A within the system will be equal to the molar flow rate of A leaving the system FA0 and this can be shown as the following, F A =F A 0−F A 0 X =F A 0 ( 1− X )

Where

F A 0=C A 0 v 0∧¿

F A 0 X=−r A V

V=

F A0 X (−r A ) exit

Since the exit composition for the reactor is identical to the composition inside the reactor, the rate of reaction is evaluated at the exit condition. 5.4 Residence of Time The reactor residence of time can be defined as the reactor volume divided by the total flow rates as the following shows, ResidenceTIme=

V CSTR F0

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6.0APPARATUS AND MATERIALS CHEMICAL USED:     

40 L of Sodium Hydroxide, NaOH (0.1 M) 40 L of Ethyl Acetate, Et(Ac) (0.1M) 1L of Hydrochloric Acid (0.25M) pH indicator De-ionised water

APPARATUS USED:      

Burette Filter funnel Beaker Conical flask Measuring cylinder Continuous Stirred Tank Reactor (model: BP143)

Figure 1: SOLTEQ-QVF Continuous Stirred Tank Reactor (model: BP143)

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7.0PROCEDURES GENERAL START-UP PROCEDURES 1. The following solution was prepared: I. 40L of Sodium Hydroxide, NaOH (0.1M) II. 40L of Ethyl Acetate, Et(Ac) (0.1M) III. 1L of Hydrochloric Acid, HCl (0.25M) for quenching 2. All the valves were initially closed. 3. The feed vessels were open as the following I. The vessel for tank B1 and tank B2 were fully opened. II. The NaOH solution was carefully poured into the tank B1 and Et(Ac) solution was poured into the tank B2. Then the vessel was closed. 4. The power for control panel was then turned on. 5. The overflow tube was adjusted to give a working volume of 10L in the reactor. 6. Valves V2, V3, V7, V8 and V11 was opened and the unit is ready for experiment GENERAL SUT DOWN PROCEDURES 1. The cooling water valve V13 was kept open to allow the cooling water to continuously flowing in. 2. Pump P1 and P2 were switched off as well as the Stirrer M1 and the Thermostat T1. 3. The liquid in the reactor was left to cool down to room temperature and after a while valve V13 was then closed. 4. Valves V2, V3, V7, V8 and V11 were opened to drain any liquid excess from the CSTR unit. 5. Lastly, the power for control panel was turned off.

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EXPERIMENTAL PROCEDURE EFFECT OF RESIDENCE TIME OF THE REACTION IN CSTR 1. Both pumps from tank 1 contain 0.1 M Sodium Hydroxide and tank 2 containing 0.1M Ethyl Acetate on the unit were opened to the fullest to let the feed flow into the 2. 3. 4. 5.

reactor. This is to obtain the highest possible flowrate. The reactor was filled up to 10L until both of the solution is about to overflow. Valve V5 and V10 is then tuned so that the flowrate of both solution is 0.1L/min. The stirrer M1 was switched on to the speed of 200rpm. The conductivity value was monitored until it was constant value and the data was

recorded. 6. 50mL of sample was collected from the exit stream and mixed with 10 ml of HCl with 3 drops of indicator. 7. The sample was then titrated with 0.25M of NaOH. 8. Step 3 to 7 was repeated with both solutions having flow rates of 0.15 L/min, 0.20 L/min, 0.25 L/min and 0.30 L/min. 9. The data was the record in the table in section 8.0.

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PREPARATION OF CALIBRATION CURVE FOR THE CONVERSION VS CONDUCTIVITY 1. The following solution were prepared : I. 1L of Sodium Hydroxide (0.1 M) II. 1L of Ethyl Acetate (0.1M) III. 1L of Deionised water, H2O 2. The conductivity and NaOH concentration for each value were determined by using the following solution with 100 mL of deionised water. I. 0% conversion : 100 mL of NaOH II. 25% conversion : 75 mL of NaOH + 25 mL of Et(Ac) III. 50% conversion : 50 mL of NaOH + 50 mL of Et(Ac) IV. 75% conversion : 25 mL of NaOH + 75 mL of Et(Ac) V. 100 % conversion : 100 mL of Et(Ac) BACK TITRATION FOR MANUAL CONVERSION DETERMINATION 1. A burette was filled up with 0.1 M NaOH solution 2. In a flask, 10 ml of 0.25 M of HCl was measured. 3. A 50 mL sample was obtained from the experiment and added to the flask that contained 10ml of 0.25 M of HCl. These steps are for quenching the saponification reaction. 4. A few drops of pH indicator were added to the mixture. 5. The mixture in the flask was titrated with NaOH solution from the burette until the mixture was neutralized which is the solution turned into pale pink colour. 6. The amount of NaOH titrated was recorded.

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8.0RESULTS AND DATA CONVERSIO N 0% 25% 50% 75% 100%

SOLUTION MIXTURES 0.1M 0.1 M H2O NaOH

Et(AC)

(mL)

100 mL 75mL 50mL 25mL -

25mL 50mL 75mL 100mL

100 100 100 100 100

CONCENTRATION

CONDUCTIVIT

OF NaOH (M)

Y

0.0500 0.0375 0.0250 0.0125 0.0000

(Ms/cm) 17.28 16.03 9.75 4.90 0.17

Conversion vs Conductivity 20 f(x) = - 0.18x + 18.7 15 R² = 0.97 conductivity 10

Linear ()

5 0 0

20

40

60

80

100 120

conversion

Figure 2: GRAPH CONVERSION VS CONDUCTIVITY

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EXPERIMENT 2 (TABLE 1)

REACTOR VOLUME

= 10 L

CONCENTRATION OF NaOH IN FEED VESSEL

= 0.1M

CONCENTRATION OF Et(Ac) IN FEED VESSEL

= 0.1M

Temperature (ºC) Flow rate of NaOH (mL/min) Flow rate of Et(Ac) (mL/min) Total Flow rate of Solution, F0 (mL/min) Volume of NaOH titrated (mL) Volume unreacted quenching HCl (mL) Volume of HCl reacted with NaOH (mL) Conductivity (mS/cm) Residence Time (min) Exit Concentration of NaOH (M) Conversion X (%) Rate Constant, k (M-1s-1) Rate of reaction, -rA (M/s)

27.6

27.6

27.8

27.9

27.9

0.10

0.15

0.20

0.25

0.30

0.10

0.15

0.20

0.25

0.30

0.2

0.3

0.4

0.5

0.6

24.7

23.8

23.0

22.5

21.9

9.88

9.52

9.20

9.0

8.76

0.12

0.48

0.80

1.00

1.24

2.53 50 0.0006

2.43 33.33 0.0024

2.23 25 0.004

2.11 20 0.005

1.99 16.67 0.0062

98.8 2744.44 9.880 x 10-4

95.2 247.94 9.880 x 10-3

92.0 115 1.840 x 10-3

90.0 90 2.250 x 10-3

87.6 68.35 2.627 x 10-3

Conversion vs Residence Time 60 50 40

f(x) = - 8x + 53 R² = 0.9

RESIDENCE TIME 30 20

Linear () 16.67

10 0 0

1

2

3

4

5

6

CONVERSION

Figure 3: GRAPH CONVERSION VS RESIDENCE TIME

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9.0CALCULATION SAMPLE CALCULATION 1 Volume of sample, Vs Concentration of NaOH in the feed vessel, CNaOH, f Volume of HCl for quenching, VHCl, S Concentration of HCl in standard solution, CHCl, S Volume of NaOH titrated, V1 Concentration of NaOH used for titration, CNaOH, S

50 mL 0.1 M 10 mL 0.25 M 24.7 mL 0.1 M

1. CONCENTRATION OF NaOH ENTERING THE REACTOR, CNaOH,O CNaOH,O = (1/2) CNaOH, S = (1/2) (0.1) = 0.05 mol/L 2. Volume of unreacted quenching HCl, V2 V2

= (CNaOH, S/CHCl, S) x V1 = (0.1/0.25) x 24.7 = 9.88 mL 3. Volume of HCl reacted with NaOH in sample, V3

V3

= VHCl, S – V2 = 10.0 – 9.88 mL = 0.12 mL 4. Moles of HCl reacted with NaOH in sample, n1

n1

= (CHCl, S x V3) / 1000 = (0.25 x 0.12) / 1000 = 0.00003 mol 5. Concentration of unreacated NaOH in the reactor, CNaOH

CNaOH

= n2/ Vs x 1000 = (0.00003/ 50) x 1000 = 0.0006 M

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6. Conversion of NaOH in the reactor, CNaOH X

= (1-

C NaOH ¿ x 100% CNaOH , 0

= (1-

0.0006 ¿ x 100% 0.05

= 98.8% 7. Residence Time, Ʈ Ʈ

= VCSTR / F0 = 10 L/ (0.1 + 0.1) L/min = 50 min 8. Reaction Rate constant, k c NaOH ,0 −c NaOH

K

=

Ʈ c NaOH 2

0.05−0.0006 = 50 ( 0.0006 )2 = 2744.44 M-1s-1 9. Rate of reaction, -rA rA

= kCA2 = (2744.44) (0.0006)2 =9.880 x 10-4 M/s

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SAMPLE CALCULATION 2 Volume of sample, Vs Concentration of NaOH in the feed vessel, CNaOH, f Volume of HCl for quenching, VHCl, S Concentration of HCl in standard solution, CHCl, S Volume of NaOH titrated, V1 Concentration of NaOH used for titration, CNaOH, S

50 mL 0.1 M 10 mL 0.25 M 23.8 mL 0.1 M

1. CONCENTRATION OF NaOH ENTERING THE REACTOR, CNaOH,O CNaOH,O = (1/2) CNaOH, S = (1/2) (0.1) = 0.05 mol/L 2. Volume of unreacted quenching HCl, V2 V2

= (CNaOH, S/CHCl, S) x V1 = (0.1/0.25) x 23.8 = 9.52 mL 3. Volume of HCl reacted with NaOH in sample, V3

V3

= VHCl, S – V2 = 10.0 – 9.52 mL = 0.48 mL 4. Moles of HCl reacted with NaOH in sample, n1

n1

= (CHCl, S x V3) / 1000 = (0.25 x 0.48) / 1000 = 0.00012 mol 5. Concentration of unreacated NaOH in the reactor, CNaOH

CNaOH

= n1/ Vs x 1000 = (0.00012/ 50) x 1000 = 0.0024 M

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6. Conversion of NaOH in the reactor, CNaOH X

= (1-

C NaOH ¿ x 100% CNaOH , 0

= (1-

0.0024 ¿ x 100% 0.05

= 95.2% 7. Residence Time, Ʈ Ʈ

= VCSTR / F0 = 10 L/ (0.15 + 0.15) L/min = 33.33 min 8. Reaction Rate constant, k c NaOH ,0 −c NaOH

K

=

Ʈ c NaOH 2

0.05−0.0024 = 33.33 ( 0.0024 )2 = 247.94 M-1s-1 9. Rate of reaction, -rA rA

= kCA2 = (247.94) (0.0024)2 = 9.880 x 10-3 M/s

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SAMPLE CALCULATION 3 Volume of sample, Vs Concentration of NaOH in the feed vessel, CNaOH, f Volume of HCl for quenching, VHCl, S Concentration of HCl in standard solution, CHCl, S Volume of NaOH titrated, V1 Concentration of NaOH used for titration, CNaOH, S

50 mL 0.1 M 10 mL 0.25 M 23.0 mL 0.1 M

1. CONCENTRATION OF NaOH ENTERING THE REACTOR, CNaOH,O CNaOH,O = (1/2) CNaOH, S = (1/2) (0.1) = 0.05 mol/L 2. Volume of unreacted quenching HCl, V2 V2

= (CNaOH, S/CHCl, S) x V1 = (0.1/0.25) x 23.0 = 9.20 mL 3. Volume of HCl reacted with NaOH in sample, V3

V3

= VHCl, S – V2 = 10.0 – 9.20 mL = 0.8 mL 4. Moles of HCl reacted with NaOH in sample, n1

n1

= (CHCl, S x V3) / 1000 = (0.25 x 0.80) / 1000 = 0.0002 mol 5. Concentration of unreacated NaOH in the reactor, CNaOH

CNaOH

= n1/ Vs x 1000 = (0.0002/ 50) x 1000 = 0.004 M

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6. Conversion of NaOH in the reactor, CNaOH X

= (1-

C NaOH ¿ x 100% CNaOH , 0

= (1-

0.004 ¿ x 100% 0.05

= 92.0% 7. Residence Time, Ʈ Ʈ

= VCSTR / F0 = 10 L/ (0.2 + 0.2) L/min = 25 min 8. Reaction Rate constant, k c NaOH ,0 −c NaOH

K

=

Ʈ c NaOH 2

0.05−0.004 = 25 ( 0.004 )2 = 115 M-1s-1 9. Rate of reaction, -rA rA

= kCA2 = (115) (0.004)2 = 1.840 x 10-3 M/s

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SAMPLE CALCULATION 4 Volume of sample, Vs Concentration of NaOH in the feed vessel, CNaOH, f Volume of HCl for quenching, VHCl, S Concentration of HCl in standard solution, CHCl, S Volume of NaOH titrated, V1 Concentration of NaOH used for titration, CNaOH, S

50 mL 0.1 M 10 mL 0.25 M 22.5 mL 0.1 M

1. CONCENTRATION OF NaOH ENTERING THE REACTOR, CNaOH,O CNaOH,O = (1/2) CNaOH, S = (1/2) (0.1) = 0.05 mol/L 2. Volume of unreacted quenching HCl, V2 V2

= (CNaOH, S/CHCl, S) x V1 = (0.1/0.25) x 22.5 = 9.00 mL 3. Volume of HCl reacted with NaOH in sample, V3

V3

= VHCl, S – V2 = 10.0 – 9.00 mL = 1.0 mL 4. Moles of HCl reacted with NaOH in sample, n1

n1

= (CHCl, S x V3) / 1000 = (0.25 x 1.0) / 1000 = 0.00025 mol 5. Concentration of unreacated NaOH in the reactor, CNaOH

CNaOH

= n1/ Vs x 1000 = (0.00025/ 50) x 1000 = 0.005 M

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6. Conversion of NaOH in the reactor, CNaOH X

= (1-

C NaOH ¿ x 100% CNaOH , 0

= (1-

0.005 ¿ x 100% 0.05

= 90.0% 7. Residence Time, Ʈ Ʈ

= VCSTR / F0 = 10 L/ (0.25 + 0.25) L/min = 20 min 8. Reaction Rate constant, k c NaOH ,0 −c NaOH

K

=

Ʈ c NaOH 2

0.05−0.005 = 20 ( 0.005 )2 = 90 M-1s-1 9. Rate of reaction, -rA rA

= kCA2 = (90) (0.005)2 = 2.250 x 10-3 M/s

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SAMPLE CALCULATION 5 Volume of sample, Vs Concentration of NaOH in the feed vessel, CNaOH, f Volume of HCl for quenching, VHCl, S Concentration of HCl in standard solution, CHCl, S Volume of NaOH titrated, V1 Concentration of NaOH used for titration, CNaOH, S

50 mL 0.1 M 10 mL 0.25 M 21.9 mL 0.1 M

1. CONCENTRATION OF NaOH ENTERING THE REACTOR, CNaOH,O CNaOH,O = (1/2) CNaOH, S = (1/2) (0.1) = 0.05 mol/L 2. Volume of unreacted quenching HCl, V2 V2

= (CNaOH, S/CHCl, S) x V1 = (0.1/0.25) x 21.9 = 8.76 mL 3. Volume of HCl reacted with NaOH in sample, V3

V3

= VHCl, S – V2 = 10.0 – 9.00 mL = 1.24mL 4. Moles of HCl reacted with NaOH in sample, n1

n1

= (CHCl, S x V3) / 1000 = (0.25 x 1.24) / 1000 = 0.00031 mol 5. Concentration of unreacated NaOH in the reactor, CNaOH

CNaOH

= n1/ Vs x 1000 = (0.00031/ 50) x 1000 = 0.0062 M

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6. Conversion of NaOH in the reactor, CNaOH X

= (1-

C NaOH ¿ x 100% CNaOH , 0

= (1-

0.0062 ¿ x 100% 0.05

= 87.6% 7. Residence Time, Ʈ Ʈ

= VCSTR / F0 = 10 L/ (0.30 + 0.30) L/min = 16.67 min 8. Reaction Rate constant, k c NaOH ,0 −c NaOH

K

=

Ʈ c NaOH 2

0.05−0.0062 = 16.67 ( 0.0062 )2 = 68.35 M-1s-1 9. Rate of reaction, -rA rA

= kCA2 = (68.35) (0.0062)2 = 2.627 x 10-3 M/s

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10.0 DISCUSSION A type of reactor where its contents are uniform throughout the reactor that is well-stirred is called Continuous Stirred Tank Reactor (CSTR). It is a real designed reactor that is almost matches the performance of ideal reactor. For the objective that needed to be achieved which is to carry out the saponification process between Sodium Hydroxide (NaOH) and Ethyl Acetate (Et(Ac)) in the reactor, to determine the effect of residence time onto conversion of reactant extent and lastly to determine the constant rate of reaction. From all the data collected, two graph was plotted which are conductivity versus conversion and residence time versus conversion. The reactor property is to be varied is the residence time and to get difference is residence times, the flow rates of both reactants from their own tank are varied. The volume of CSTR can b e referred to the volume of the reactor which is 10 L and F 0 is the flow rate of the feed that can be varies to get difference in residence time, Ʈ. The flowrate to be varied in the experiment are 0.1L/min, 0.15 L/min, 0.20 L/min, 0.25 L/min and 0.30 L/min which can be seen in data collected in table 1.Referring to the data collected in table 1, the residence time are determined to be 50 min, 33.33 min, 25 min, 20 min and 16.67 min respectively which are included in the table 1 and the residence time were successfully done. From the graph 1 which is the conductivity versus conversion, we can conclude that the conductivity is not consistent with slope of 18.69. While from the graph 2 which is the residence time versus conversion, we can conclude that the residence time increases proportionally with the conversion. But there is some fluctuate which due to the error that may be affecting the result and graph of the experiment. For the saponification process, it is a continuous process reaction. In this experiment, the reaction of saponification is quenching with the hydrochloric acid to neutralize the reaction. The reaction rapidly reacts in increasing of experiment. To investigate if the reaction is stop, the back titration method was used. The are some error occurred during the process of this experiment such as while taking reading of the burette, the position of eyes is not the same level of the meniscus and in order to improve the quality of result, the position of eyes must be parallel to the meniscus. More than that, we have to make sure the apparatus that we are using is clean properly. This is to

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ensure the sample would not react with any other chemical that is not used in order to more accurate reading of data to analysis.

11.0

CONCLUSION

Based on the objectives of this experiment achieved which is to carry out the saponification process between Sodium Hydroxide (NaOH) and Ethyl Acetate (Et(Ac)) in the reactor, to determine the effect of residence time onto conversion of reactant extent and lastly to determine the constant rate of reaction. We can conclude that the experiment was successfully conducted even with some error occurred during the process based on the data that we have collected and analysis. For the experiment 1, it can be seen that the calibration curve plotted was quite similar to the theoretical part. The reaction rate have been determined to be 9.880 x 10 -4M/s, 9.880 x103

M/s, 1.840 x 10-3M/s, 2.250 x 10-3M/s and 2.627 x 10-3M/s respectively.

12.0 RECOMMENDATION 1. It is better to prepare the Hydrochloric acid first, so that when the sample is collected, it can be quickly quenched. This will avoid any further reaction of the sample after it was collected. 2. The indicator should be mixed with the same amount to the acid first, and then the sample was added and titrated. 3. Titration should be immediately stopped when the indicator turns pale pink colour. 4. Pumps should never be run dry. 5. Always handle the chemical solution with glove to avoid any corrosion happened during the experiment. 6. Always make sure that the eyes were parallel to the level of meniscus.

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13.0 REFERENCES  Operating & Experiment Manual, Continuous Stirred Tank     

Reactor(Model:Bp143) Fogler, H.S (2006), Element of Chemical Reaction Engineering (3rd ed.) New Jersey; Prentice Hall. Levelspiel. O, Chemical Reaction Engineering, John Wiley, 1972 Robert H. Perry, Don W. Green, Perry’s Chemical Engineer’s Handbook, McGraw Hill,1998 Smith J.M Chemical Engineering Kinetics, McGraw Hill,1981 McCabe, Unit Operation of Chemical Engineering, 2005

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