VLE Lab Report 2015ssda

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    TABLE OF CONTENT

    No Title Page1 Abstract. 2

    2 Introduction.. 3

    3 Objectives.. 4

    4 Theory... 56

    5 Material And Apparatus 79

    6 Methodology. 1014

    7 Data and Results 15168 Calculations... 1727

    9 Discussion. 2831

    10 Conclusion. 32

    11 Recommendations. 33

    12 Reference... 34

    13 Appendix... 3537

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    1.0 ABSTRACT

    The experiment are carried out to study the relationship between vapour and liquid at

    equilibrium and at atmospheric pressure. The experiment was also conducted to build or

    construct the equilibrium curves at atmospheric pressure for binary system namely methanol and

    water. The experiment was carried out using the Vapour Liquid Equilibrium (VLE) unit. A

    mixture of methanol-water with known composition is initially fed into the evaporator. When the

    heater is switched on, the mixture will start to boil. The mixture vapour will rise up and will be

    cool down by the condenser at the top of the evaporator. The system will stabilize and finally

    reach an equilibrium state when temperature remains constant. Samples of vapour and liquid are

    taken to determine their compositions.

    At the end of the experiment, a graph of mole fraction of vapour against mole fraction of

    liquid and a graph of temperature against mole fraction of liquid and vapour were plotted. This

    equilibrium curves at atmospheric pressure for binary system namely methanol and water clearly

    shows the relationship between vapour and liquid at equilibrium and at atmospheric pressure. It

    can be said that from the graph that we had plotted, the relationship between vapour and liquid at

    equilibrium and at atmospheric pressure is that they exist in linear. The experiment wasconsidered a success as all the objectives were achieved as we want.

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    2.0 INTRODUCTION

    Vapour-Liquid Equilibrium (VLE) can be defined as a condition where liquid and vapour

    are in equilibrium to each other. Rate of liquid evaporated to vapour s is the same as rate of

    vapour condensed into liquid. It is called equilibrium state when there is no net rate difference,

    this vapour-liquid interconvertions is zero. For pure Substance, it is implies at the boiling point.

    The purpose of this experiment using Vapour-Liquid Equilibrium is to construct an

    equilibrium curve for methanol and water system at atmosphere pressure. The mixture of

    methanol and water is fed into the evaporator. After the heater is on, the mixture is left to boil.

    The evaporated vapour then rise and cooled down by the condenser. The condensed liquid will

    fall back into the evaporator. This cycle continues until it reach the equilibrium state, when the

    temperature become constant.

    The sample of the liquid and the vapour are taken for test. By using the Refractometer,

    we can determine the composition of the mixture or the Refractive Index (RI). Refractive Index

    is define as the ratio of velocity of light in a vacuum to its velocity in a specified medium. An

    example for the application of Vapour-Liquid Equilibrium (VLE) in an equipment is the

    Distillation Column. In the equipment, the VLE concept are used. The reboiler in the column is

    used to boil the necessary mixture and the condenser is used to cool down the vapour.

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    3.0 OBJECTIVE

    1. To investigate the relationship between the vapour and liquid at different temperature.

    2. To construct the equilibrium curve for methanol-water system at atmospheric pressure, 1

    atm.

    3. To understand the concept of Vapour-Liquid Equilibrium (VLE) thoroughly.

    4. To find out the application for the Vapour-Liquid Equilibrium (VLE).

    5. To differentiate the plotted graph between Refractive Index (RI) and range of

    composition mixtures based on the experimental data obtained.

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    4.0 THEORY

    Vaporliquid equilibrium (VLE) is a condition in which aliquid and itsvapor (gas phase) are

    inequilibrium with each other, a condition or state where the rate ofevaporation(liquid changing

    to vapor) equals the rate ofcondensation (vapor changing to liquid) on a molecular level suchthat there is no net (overall) vaporliquid inter conversion. A substance at vaporliquid

    equilibrium is generally referred to as a saturated fluid. For a pure chemical substance, thisimplies that it is at itsboiling point. The notion of "saturated fluid" includes saturated liquid

    (about to vaporize), saturated liquidvapor mixture, andsaturated vapor (about to condense).

    The Vapor-Liquid Equilibrium is used to determine the equilibrium in binary phase by

    vaporization and diffusion. Binary mixtures are mixtures of two component and two phase

    system. These mixtures are said to be in equilibrium when their internal properties reaches thesame reading. The four internal properties are the reading of temperature, pressure, liquid mol

    fractions and vapor mol fractions. According to the phase rule, the condition of two phase

    system, when two intensive properties are specified, the extensive properties may be differed.

    But, in equilibrium, the intensive properties will be counted.

    In this experiment, we use water and methanol which both are in pure substance and in binary

    mixtures. Water and methanol are ideal mixtures so it obeys Raoults Law.

    For Raoults Law being applied in this experiment, for ideal gas vapor mixture in equilibrium

    ideal solution, equation becomes:

    PA = XAPA0

    Where,

    PA =partial pressure of component A in a solution

    PA0

    = vapor pressure of pure A

    XA =mole fraction of component A in a solution

    Gives the mole fraction of component A in the gas phase as

    yA = XAPAA0

    P

    http://en.wikipedia.org/wiki/Liquidhttp://en.wikipedia.org/wiki/Vaporhttp://en.wikipedia.org/wiki/Chemical_equilibriumhttp://en.wikipedia.org/wiki/Evaporationhttp://en.wikipedia.org/wiki/Condensationhttp://en.wikipedia.org/wiki/Boiling_pointhttp://en.wikipedia.org/wiki/Saturated_vaporhttp://en.wikipedia.org/wiki/Saturated_vaporhttp://en.wikipedia.org/wiki/Boiling_pointhttp://en.wikipedia.org/wiki/Condensationhttp://en.wikipedia.org/wiki/Evaporationhttp://en.wikipedia.org/wiki/Chemical_equilibriumhttp://en.wikipedia.org/wiki/Vaporhttp://en.wikipedia.org/wiki/Liquid
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    Extend to the binary system, Raoults Law and Dalton Law equation:

    P = pA + pB = XAPA + (1- XA)Pb = XA(PAPB) + PB

    OR

    XA = P - PB

    PA - PB

    The equations is used to find XA for ideal binary mixtures at selected temperatures between the

    boiling temperatures of two pure components at given pressure.

    The distribution coefficient or have just K-value for the component i,

    yA = Kixi

    Raoults and Daltons Law gives the reasonable estimates and the value of mole fraction, partial

    pressure can be determined by using these laws at equilibrium state.

    To find the composition of water and methanol, this equation was used

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    5.0 MATERIAL AND APPARATUS

    Material :-

    1. Methanol

    2.

    Distilled Water

    Apparatus:-

    1. SOLTEQ Vapour Liquid Equilibrium Unit (Model : BP 16)

    2. Dropper

    3. Sample Collector

    4. Refractometer

    5. 2-L measuring cylinder

    6.

    500-ml measuring cylinder7. 500-ml measuring beaker

    8. Goggles

    9. Gloves

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    Figure 1 Unit Construction for Vapour Liquid Equilibrium Unit (Model : BP16)

    1.

    Condenser 6. Pressure Relief Valve

    2. Evaporator 7. Control Panel

    3. Bottom Sample Collector 10.Top Sample Collector

    4. Cooling Water Supply 11.Rotameter

    5. Cooling Water Drain 12.Heater

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    Figure 2 Process Flow Diagram for the Vapour-Liquid Equilibrium Unit

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    6.0 METHODOLOGY

    6.1) General Start-up Procedures

    1.

    The equilibrium data for the binary system to be studied is obtained fromliterature.

    2. A calibration curve of refractive index vs. composition plot fo the particularbinary system is prepared by referring at calibration table for methanol-water.

    3. The evaporator and condenser are checked to make sure they are empty of liquid.

    4. Ensuring that all the valves are initially closed and the heater power switch is

    turned off.5. The main power is switch on at the control panel. All sensors and indicators are

    checked to make sure they are functioning properly.

    6.2) General Experiment Procedures

    1. About 3 to 6-L of liquid mixture at the desired composition is prepared and

    poured into the evaporator through valve V1. The valve V1 is closed.2. Valves V13 and V14 at the level sight tube is opened. The liquid level is

    determined to be above the safety line on the level sight tube. The valves, V13

    and V14 are closed back.3. Valve V8 is opened to make sure the operation is at atmospheric pressure.

    4. Valve V10 is opened and adjusted to allow about 5 to 10-L/min of cooling water

    to flow through the condenser.

    5. The temperature controller TIC-01 is set to slightly above the expected boilingpoint of the liquid mixture.

    6.

    The heater is switched on.7. The temperature rise in TIC-01 is observed. When the temperature at TI-02started to increase sharply, the liquid in the evaporator is determined to begin

    boiling. The pressure at PI-01 is observed. Temperature and pressure are waited to

    stabilize at a steady state value.

    8. The evaporator pressure and the liquid and vapour temperatures are recorded.9. A vapour and liquid sample from the unit is collected as described in Sampling

    Procedure.

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    6.3) General Shut-down Procedures

    1. The heater is switched off.2. Valve V10 is opened to increase the cooling water flow rate through the

    condenser.

    3.

    Valve V11 is opened to allow the cooling water to flow through the cooling coilin the evaporator.

    4. The temperature at the unit is waited to drop to below 50C.

    5. Valves V2 and V3 are opened to drain all liquid from the evaporator.

    6. Valves V5 and V7 are opened to drain all liquid accumulated at the condenser.

    7. All the valves are closed and the main power is switched off at the control panel.

    6.4) Sampling Procedure

    Both vapour and liquid samples from the unit are taken out for analysis.The sample volume that is taken is minimum, less than 25ml. This is to avoid any effect

    on the volume remained in the evaporator.

    1. Vapour sampling from the condenser

    i. Ensuring that the vent valve V6 is opened and drained valve V7 is closed.ii. Valve V5 is opened slowly to allow some condensed vapour from the

    condenser to flow into the top sample collector. Valve V5 is closed.

    iii. Valve V7 is opened to collect the sample in a sampling vial.iv.

    The cap on the vial is immediately closed and immersed the sample in

    cold water.

    2.

    Liquid sampling from the evaporator

    i. Ensuring that the vent V4 is opened and drain valve V3 is closed.

    ii. Valve V12 is opened to allow cooling water to flow through the bottom

    sample collector.iii. Valve V2 is opened slowly to allow some liquid from the evaporator to

    flow into the sample collector. The valve V2 is closed.

    iv. Valve V3 is opened to collect the sample in a sampling vial.v. The cap on the vial is immediately closed and immersed the sample in

    cold water.

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    6.5) Experiment 1 : Equilibrium Curve at Atmospheric Pressure

    1. The general start-up procedures as described in Section 6.1 is performed.2. About 12-L of pure methanol and 5-L of deionized water is prepared.

    3. Valve V8 is opened.

    4.

    0.1-L methanol and 3-L water are poured into the evaporator through valve V1.Valve V1 is closed.5. Valves V13 and V14 at the level sight tube is opened. The liquid level is

    determined to be above the safety line on the level sight tube. The valves V13 and

    V14 is closed back.6. Valve V10 is opened and adjusted to allow about 5L/min of cooling water to flow

    through the condenser.

    7. The temperature controller TIC-01 is set to about 100C. The heater is switched

    on.

    8. The temperature rise in TIC-01 is observed. When the temperature at TI-02started to increase sharply, the liquid in the evaporator is determined to began

    boiling. The pressure at PI-01 is observed. All the temperatures and pressure arewaited to stabilize at a steady state value.9. The evaporator pressure and the liquid and vapour temperatures are recorded.

    10.A liquid and vapour sample from the unit is collected as described in Section 6.4.

    The samples are analyzed to determine their compositions.11.The heater is switched off and valve V11 is opened to allow cooling water to flow

    through the cooling coil in the evaporator.

    12.The temperature drop at TI-02 is observed and waited to drop significantly whichsignify that boiling has stopped. Valve V11 is closed.

    13.All the liquid from the condenser is collected by opening valve V5 and V7 and

    the liquid is poured back into the evaporator through valve V1. Valves V5 and V7

    are closed.14.

    All the liquid from the bottom sample collector is collected by opening valve V3

    while closing valve V2 and the liquid is poured back into the evaporator through

    valve V1. The valves V3 and V1 is closed.

    15.An additional 0.2-L methanol is poured into the evaporator through valve V1.Valve V1 is closed. Now, there is about 0.3-L methanol and 3-L water in the

    evaporator. Steps 5 to 14 above is repeated.

    16.An additional 0.2-L methanol is poured into the evaporator through valve V1.Valve V1 is closed. Now, there is about 0.5-L methanol and 3-L water in the

    evaporator. Steps 5 to 14 above is repeated.

    17.An additional 0.5-L methanol is poured into the evaporator through valve V1.

    Valve V1 is closed. Now, there is about 1-L methanol and 3-L water in theevaporator. Steps 5 to 14 above is repeated.

    18.An additional 1-L methanol is poured into the evaporator through valve V1.

    Valve V1 is closed. Now, there is about 2-L methanol and 3-L water in theevaporator. Steps 5 to 14 above is repeated.

    19.An additional 1-L methanol is poured into the evaporator through valve V1.

    Valve V1 is closed. Now, there is about 3-L methanol and 3-L water in theevaporator. Steps 5 to 14 above is repeated.

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    20.Valves V2 and V3 is opened to drain all liquid from the evaporator.

    21.2-L methanol and 1-L water are poured into the evaporator through valve V1.

    Valve V1 is closed.22.An additional 1-L methanol is poured into the evaporator through valve V1.

    Valve V1 is closed. Now, there is about 3-L methanol and 1-L water in the

    evaporator. Steps 5 to 14 above is repeated.23.An additional 2-L methanol is poured into the evaporator through valve V1.Valve V1 is closed. Now, there is about 5-L methanol and 1-L water in the

    evaporator. Steps 5 to 14 above is repeated.

    24.The general shut-down procedures is performed as described in Section 6.3.

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    6.6) Safety Precautions :-

    1. The unit is operated under the supervision of an authorized staff who has beenproperly trained to handle the unit.

    2.

    All operating instructions supplied with the unit is carefully read and understoodbefore attempting to operate the unit.

    3. Always make sure that there is enough liquid all the time to fully submerge the

    heater and temperature sensor.

    4. Be extremely careful when handling liquid at high temperature.

    5. Always switch off the heater and allow the liquid to cool down before draining.

    6. Do not touch the hot components of the unit.

    7.

    Feed stock which severely affect stainless steel 304 and polypropylene (PP) are

    not to be used.

    8. The system should not be subjected to shock, sudden impact, vibration, oradditional load.

    9. Restore the system to operating conditions after any repair job.

    10.Always check and rectify any leak.

    11.Do not exceed the maximum cooling water pressure of 2 bar(g) for the condenser.

    12.Be extremely careful when handling hazardous, flammable or polluting materials.

    13.Do not stretch the Viton O-rings during servicing.

    14.Make sure the system is sufficiently ventilated at all times during operation,maintenance and storage.

    15.Only properly trained staff shall be allowed to carry out any servicing or repair

    job. Manufacturer's manual must always be observed.

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    7.0 DATA AND RESULTS

    Table 1 : Calibration Table For Methanol-Water

    Volume ofMethanol

    (mL)

    Volume ofWater

    (mL)

    Mol fraction wt% Refractive index(RI)

    0 10 0.0000 0.00 1.332

    1 9 0.0470 8.07 1.336

    2 8 0.1000 16.49 1.338

    3 7 0.1598 25.29 1.340

    4 6 0.2283 34.50 1.342

    5 5 0.3074 44.13 1.343

    6 4 0.3997 54.23 1.343

    7 3 0.5087 64.83 1.343

    8 2 0.6390 75.96 1.3349 1 0.7996 87.67 1.330

    10 0 1.000 100.00 1.332

    Table 2 : Methanol and Water properties

    Methanol

    (99.7%)

    Water

    0.79 1

    32.04 18

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    Table 3 : The Methanol-Water system

    Pressure Volume

    Methanol

    Volume

    WaterTemperature (C) RI

    Liquid Vapour Liquid Vapour

    1 atm 0.1 3 98.0 92.5 1.338 1.339

    0.3 3 94.9 89.4 1.332 1.3370.5 3 92.4 87.4 1.333 1.338

    1 3 87.5 83.0 1.332 1.338

    2 3 82.2 78.8 1.333 1.336

    3 3 79.8 76.8 1.333 1.337

    2 1 74.9 72.3 1.334 1.336

    3 1 73.7 71.1 1.336 1.332

    5 1 70.9 69.4 1.336 1.331

    Composition Experiment Composition Literature % error

    Liquid Vapour Liquid Vapour Liquid Vapour

    0.0195 0.0195 0.0150 0.2655 -30.00 92.660.0566 0.0568 0.0336 0.3727 -68.45 84.76

    0.0918 0.0922 0.0512 0.4268 -79.30 78.40

    0.1717 0.1724 0.1006 0.5470 -70.68 68.48

    0.3044 0.3050 0.1871 0.6534 -62.69 53.32

    0.4098 0.4110 0.2494 0.6969 -64.31 41.02

    0.6273 0.6282 0.4209 0.8053 -49.04 21.99

    0.7630 0.7607 0.4780 0.8308 -59.62 8.44

    0.9210 0.9175 0.6240 0.8721 -47.60 -5.21

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    8.0 CALCULATIONS

    Calculation for mole fraction of methanol of the calibration table:-

    Volume of Methanol Volume of Water0mL 10mL

    No of mol of solute

    No of mol of solvent

    ( )

    Volume of Methanol Volume of Water

    1mL 9mL

    No of mol of solute

    No of mol of solvent

    ()

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    Volume of Methanol Volume of Water

    2mL 8mL

    No of mol of solute

    No of mol of solvent

    ()

    Volume of Methanol Volume of Water

    3mL 7mL

    No of mol of solute

    No of mol of solvent

    ()

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    Volume of Methanol Volume of Water

    4mL 6mL

    No of mol of solute

    No of mol of solvent

    ()

    Volume of Methanol Volume of Water

    5mL 5mL

    No of mol of solute

    No of mol of solvent

    ()

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    Volume of Methanol Volume of Water

    6mL 4mL

    No of mol of solute

    No of mol of solvent

    ()

    Volume of Methanol Volume of Water

    7mL 3mL

    No of mol of solute

    No of mol of solvent

    ()

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    Volume of Methanol Volume of Water

    8mL 2mL

    No of mol of solute

    No of mol of solvent

    ()

    Volume of Methanol Volume of Water

    9mL 1mL

    No of mol of solute

    No of mol of solvent

    ()

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    Volume of Methanol Volume of Water

    10mL 0mL

    No of mol of solute

    No of mol of solvent

    ()

    Calculation for the composition experiment :-

    Volume of Methanol Volume of Water

    0.1L 3L

    No of mol of solute

    No of mol of solvent

    For Liquid ,

    ()

    For Vapour , ()

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    Volume of Methanol Volume of Water

    0.3L 3L

    No of mol of solute

    No of mol of solvent

    For Liquid ,

    ()

    For Vapour , ()

    Volume of Methanol Volume of Water

    0.5L 3L

    No of mol of solute

    No of mol of solvent

    For Liquid ,

    ()

    For Vapour ,

    ()

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    Volume of Methanol Volume of Water

    1L 3L

    No of mol of solute

    No of mol of solvent

    For Liquid ,

    ()

    For Vapour ,

    ()

    Volume of Methanol Volume of Water

    2L 3L

    No of mol of solute

    No of mol of solvent

    For Liquid ,

    ()

    For Vapour ,

    ()

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    Volume of Methanol Volume of Water

    3L 3L

    No of mol of solute

    No of mol of solvent

    For Liquid ,

    ()

    For Vapour ,

    ()

    Volume of Methanol Volume of Water

    2L 1L

    No of mol of solute

    No of mol of solvent

    For Liquid ,

    ()

    For Vapour ,

    ()

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    Volume of Methanol Volume of Water

    3L 1L

    No of mol of solute

    No of mol of solvent

    For Liquid ,

    ()

    For Vapour ,

    ()

    Volume of Methanol Volume of Water

    5L 1L

    No of mol of solute

    No of mol of solvent

    For Liquid ,

    ( )

    For Vapour ,

    ( )

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    Table 4 : Mol Fraction of methanol and water

    Volume

    Methanol

    (L)

    Volume

    Water

    (L)

    Moles of

    CH3OH

    (mol)

    Moles of

    H2O

    (mol)

    Moltotal

    CH3OH + H2O

    (mol)

    Mol fraction

    CH3OH

    (

    )

    Mol fraction

    H2O

    (

    )

    0.1 3 2.4657 166.6667 169.1327 0.0146 0.98540.3 3 7.3970 166.6667 174.0640 0.0425 0.9575

    0.5 3 12.3283 166.6667 178.9953 0.0689 0.9311

    1 3 24.6567 166.6667 191.3237 0.1289 0.8711

    2 3 49.3134 166.6667 251.9804 0.1957 0.6614

    3 3 73.9700 166.6667 240.6370 0.3074 0.6926

    2 1 49.3134 55.5556 104.8694 0.4702 0.5298

    3 1 73.9700 55.5556 129.5260 0.5711 0.4289

    5 1 123.283 55.5556 178.8390 0.6894 0.3106

    Table 5 : Composition of methanol in Mol fraction

    Mol fraction

    CH3OH

    ( )

    Refractive Index Mole fraction

    Liquid Vapour Liquid Vapour

    0.0146 1.338 1.339 0.0195 0.0195

    0.0425 1.332 1.337 0.0566 0.0568

    0.0689 1.333 1.338 0.0918 0.0922

    0.1289 1.332 1.338 0.1717 0.1724

    0.1957 1.333 1.336 0.3044 0.3050

    0.3074 1.333 1.337 0.4098 0.4110

    0.4702 1.334 1.336 0.6273 0.62820.5711 1.336 1.332 0.7630 0.7607

    0.6894 1.336 1.331 0.9210 0.9175

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    9.0 DISCUSSION

    Table 6 : Temperature and mol fraction of Methanol

    Temperature (C) Mole fraction of Methanol

    Liquid Vapour Liquid Vapour

    98.0 92.5 0.0195 0.0195

    94.9 89.4 0.0566 0.0568

    92.4 87.4 0.0918 0.0922

    87.5 83.0 0.1717 0.1724

    82.2 78.8 0.3044 0.3050

    79.8 76.8 0.4098 0.4110

    74.9 72.3 0.6273 0.6282

    73.7 71.1 0.7630 0.7607

    70.9 69.4 0.9210 0.9175

    0

    20

    40

    60

    80

    100

    120

    1 2 3 4 5 6 7 8 9

    Temp

    erature(C)

    Vapour/Liquid Mole Fraction (x/y)

    T-xy Diagram for Methanol-Water System

    Liquid

    Vapour

    0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

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    0

    0.2

    0.4

    0.6

    0.8

    1

    1.2

    0 0.2 0.4 0.6 0.8 1 1.2

    Vapourmolfraction

    Liquid mol fraction

    X-Y Equilibrium Diagram for Methanol-Water

    System at 1atm

    0

    0.1

    0.2

    0.3

    0.4

    0.5

    0.6

    0.7

    0.8

    0.9

    1

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

    VapourMolFraction

    Liquid Mol Fraction

    X-Y Equilibrium Graph

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    Table 7: Refractive Index and Mol Fraction of methanol from calibration table

    Volume of Methanol

    (mL)

    Mol fraction Refractive index (RI)

    0 0.0000 1.332

    1 0.0470 1.3362 0.1000 1.338

    3 0.1598 1.340

    4 0.2283 1.342

    5 0.3074 1.343

    6 0.3997 1.343

    7 0.5087 1.343

    8 0.6390 1.334

    9 0.7996 1.330

    10 1.000 1.332

    1.328

    1.33

    1.332

    1.334

    1.336

    1.338

    1.34

    1.342

    1.344

    1.346

    0 0.2 0.4 0.6 0.8 1 1.2

    RefractiveIndex

    Mol fraction

    Refractive index (RI)

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    This experiment is carried out to investigate the relationship between vapour and liquid

    of binary mixture (methanol and water) at equilibrium at 1 atm. The equilibrium curve at 1 atm

    (atmospheric pressure) for methanol and water can be construct. The Vapour-Liquid Equilibrium

    (VLE) unit are used to carried out the experiment.

    A mixture of methanol-water with known composition is initially fed into the evaporator.

    When the heater is switched on, the mixture will start to boil. The mixture vapour will rise up

    and will be cooled down by the condenser at the top of the evaporator. As the vapour starts to

    condense, the liquid falls back into the evaporator. The system will stabilize and finally reach an

    equilibrium state when temperature remains constant. Samples of vapour and liquid are taken to

    determine their compositions. The reading is observe and recorded. The graph x-y diagram is

    construct as Vapour at axis X and Liquid at axis Y. The VLE diagram will show the Bubble

    Point, first drop of liquid mixture begins to vaporize, and the Dew Point, the first point gaseous

    start to condense into liquid form.

    Based on the data recorded, the point can be plot and eventually a line can be obtained. The

    relationship of vapour and liquid at equilibrium and at 1 tm or atmospheric pressure is shown to

    exist in linear. Then, the graph of T-xy can be plotted. This graph represents data for 2

    component (Binary) system. The system are Temperature against Mole fraction of vapour and

    Temperature against Mole fraction of liquid. After the Refractive Index (RI) for vapour and

    liquid are recorded, the graph for RI can be plotted and the bell-like shape graph is obtained.

    By using the calculation of density for each compound , the Mole fraction of vapour and

    liquid can be find out. The density of methanol is 0.79 g/cm whereas the density of water is 1

    g/cm. By using the density and the volume of methanol and water that we used , we can figure

    out the mass of the water and the methanol.

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    10.0 CONCLUSION

    In a conclusion, the experiment was carried out successfully by following the correct

    procedures. The objective by doing this experiment is to determine the vapor-liquid equilibrium

    conditions for the binary methanol-water system and correlate the results for use in the analysis

    of the distillation column. Explore the conditions for which Daltons and Raoults laws are

    adequate to describe the vapor-liquid equilibrium. Moreover by doing this experiment, we were

    able to construct and plot the graph of temperature versus vapor/ liquid mole fraction and vapor

    mol fraction versus liquid mol fraction graph. In a meantime, by doing calculation and obtaining

    data, we can get the graph that are mention above. Thus, the relationship between the vapor and

    liquid at 1 atm was successfully determined. The maximum mole fraction of methanol is 1. Theobjective of this experiment also to construct an equilibrium curve for methanol- water

    system at atmospheric pressure. From the data that we obtain, the composition of methanol in

    vapor is higher than the liquid. The composition of methanol in vapor and liquid is increase

    when the volume of methanol is also increase. When the objective of this experiment was

    achieved, it can be concluded that this experiment was successfully done.

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    11.0 RECOMMENDATION

    To improve the experiment and obtaining the best result, the experiment should have

    been repeated three times in order to get the average readings and to get the reading more

    accurately. This will reduce the deviation from theoretical result and reduce the error of reading.

    Besides, the experiment itself took more than four hours to be done once, however due to

    limitation of time, the experiment could only be done once. Therefore, to get better results, the

    experiment should have been repeated twice.

    In addition, we also can compare our result to the other group or we can make a groupdiscussion with the other group to make sure that our results are accurate or not. We should also

    increase our knowledge on how to handle the experiment better.

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    12.0 REFERENCE

    1. Yunus A. Cengal & Michael A. Boles, Thermodynamics An Engineering Approach,

    3rd

    Edition, 4th

    Edition, McGraw Hill, 2002.

    2. T. M. Duncan and J. A. Reimer, Chemical Engineering Design and Analysis : AnIntroduction, Cambridge University Press, 1998.

    3. Gmehling, J. and Onken, U, Vapor-Liquid Equilibrium Data Collection, Dechema,

    Frankfurt, Germany, Vol. 1, Page 60, 1977.

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    13.0 APPENDIX

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