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<ul><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 1/34</p><p>CHAPTER 1</p><p>Mohd Asmadi Bin Mohammed Yussuf</p><p>Faculty of Chemical Engineering</p><p>Universiti Teknologi Malaysia, 81310 UTM</p><p>Johor, Johor Bahru, Malaysia</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Introduction to Chemical</p><p>Engineering Thermodynamics</p><p>N02 2-6, 11.00 1.00P.M Feb 10, 2013 (Mon)</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 2/34</p><p>Week Topic Topic Outcomes</p><p>1 Introduction to Chemical</p><p>Engineering Thermodynamics</p><p> Overview of thermodynamic</p><p>application in chemical</p><p>industry</p><p> Application of thermodynamic</p><p>properties and equations inchemical process</p><p>It is expected that students are</p><p>able to:</p><p> Describe the importance of</p><p>chemical engineering</p><p>thermodynamics in chemical</p><p>engineering profession.</p><p> Apply the thermodynamicsproperties in the chemical process</p><p>simulators.</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Topic Outcomes</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 3/34</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Scope of Lecture</p><p>Overview of thermodynamic appl icat ion</p><p>in chem ical indus try</p><p>Appl icat ion of thermodynam ic propert ies</p><p>and equat ions in chem ical process</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 4/34</p><p>Thermodynamic Applications</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 5/34</p><p>Definition</p><p>The study of the effects of work, heat and energy on thesystem).</p><p> Only concerned with large scale observations.</p><p>Ref: NASA . Available from: http://www.grc.nasa.gov/WWW/k-12/airplane/thermo.html. (Accessed 8 Feb, 2013).</p><p>0thLaw:</p><p>Thermodynamic</p><p>equilibrium, temperature</p><p>1st Law:</p><p>Work, heat, energy</p><p>2ndLaw:</p><p>Entropy</p><p>3rdLaw:</p><p>As the T of a substance</p><p>approaches absolute zero</p><p>itsentropy approaches zero</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 6/34</p><p>Applications of Thermodynamics</p><p>Types of process applications of thermodynamics, namely:</p><p>Ref: Edmister W C (1945) Applications of Thermodynamics to the Process Industries. Journal of Chemical Education. pp13 - 19</p><p>Combustion</p><p>Heat balances</p><p>Power</p><p>Phase equilibrium</p><p>Chemical reaction equilibrium</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 7/34</p><p>Chemical Engineer &amp; Thermodynamics</p><p>Why is thermodynamics useful to chemical engineers?</p><p>Heat transfer</p><p>Mass transfer</p><p>Separation process</p><p>Chemical reactions</p><p>Ref: Girard-Lauriault P-L . Chemical Engineering Thermodynamics</p><p> CHEE220. (Accessed 8 Feb, 2013); Selis . KMU 220 -</p><p>Chemical Engineering Thermodynamics (Accessed 8 Feb, 2013)</p><p>Calculation of heat and work requirements for physical and</p><p>chemical processes.</p><p>Transfer of chemical</p><p>species between phases</p><p>Determination of</p><p>equilibrium conditions</p><p>Physical processes</p><p>(e.g. distillation)</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 8/34</p><p>Chem. Engineer &amp; Thermo. (Cont.)</p><p>Thermodynamics permits</p><p>to determine how far</p><p>processes will proceed.</p><p>Chemical kinetics</p><p>helps evaluate how</p><p>fast.</p><p>The 2 concepts are at the base of many of the</p><p>considerations of Chemical Engineers.</p><p>Ref: Girard-Lauriault P-L . Chemical Engineering Thermodynamics</p><p> CHEE220. (Accessed 8 Feb, 2013); Selis . KMU 220 -</p><p>Chemical Engineering Thermodynamics (Accessed 8 Feb, 2013)</p><p> Deals with driving force</p><p> Does not deal with RATEs of</p><p>physical or chemical phenomena.</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 9/34</p><p>Examples</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 10/34Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Manufacture of Ethylene Glycol</p><p>Desired reactionH2C CH2 1/2O2</p><p>CatalystH2C CH2</p><p>O</p><p>+</p><p>H = 24.7 kcal/gmole</p><p>Need to be heated to 250 C before enter the reactor</p><p>To design the preheater</p><p>MUST KNOW HOW MUCH HEAT IS TRANSFERRED</p><p>CATALYTIC OXIDATION REACTIONMost effective when carried out at T 250 C</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 11/34</p><p>T</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Undesired Reaction</p><p>H2C CH2 3O2+ 2CO2 + 2H2O</p><p>H = 320 kcal/gmole</p><p>Combustion reaction</p><p>Tend to raise the temperature</p><p>Heat is removed from reactor</p><p> T does not rise much above 250 C</p><p>To design the reactor</p><p>REQUIRES KNOWLEDGE OF THE RATE OF HEAT TRANSFER</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 12/34Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Hydrolysis Reaction</p><p>H2C CH2</p><p>O + H2O HOCH2CH2OH</p><p>Recovered by distillation,vaporization &amp; condensation</p><p>Heat evolved because of</p><p> Phase change</p><p> Dissolution process</p><p> Hydration reaction between the</p><p>dissolved ethylene oxide and H2O</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 13/34</p><p>CSTRs with Heat Exchanger</p><p>Ref: Fogler H S (1999). Chapter 8: Elements of Chemical Reaction Engineering, 3rd Ed. Prentice Hall. Pp 426 477; CSTR:</p><p>Continuous stirred-tank reactor.</p><p>Continuous-flowreactors</p><p>outoutinin EFEFWQdt</p><p>Ed </p><p>0HFHFWQ i</p><p>n</p><p>1i</p><p>ii0</p><p>n</p><p>1i</p><p>i0s </p><p>At steady state,</p><p>CSTR with heat exchange</p><p> n</p><p>1i</p><p>i0piiRpR</p><p>o</p><p>RX</p><p>A0</p><p>a T-TCTTC)( THXF</p><p>TTUA ~</p><p> RPRRX</p><p>i0pii</p><p>A0</p><p>a</p><p>EBTTC)( TH</p><p>TTCF</p><p>TTUA</p><p>X</p><p>~</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 14/34</p><p>Determination of X &amp; T</p><p>5. Energy Balance (Calculate XEB)</p><p>6. Calculate XMB</p><p>Elementary irreversible liquid phase reaction A B</p><p>Non-adiabatic</p><p>RX</p><p>0PAA0aEB</p><p>H</p><p>)T( TC) /FTUA( TX</p><p>~</p><p>A0</p><p>A0</p><p>0MB F</p><p>VC</p><p>V</p><p>;.k1</p><p>.k</p><p>X </p><p>E/RTAek </p><p>7. Plot X vs. T</p><p>X</p><p>T</p><p>XEB</p><p>XMB</p><p>Ref: Fogler H S (1999). Chapter 8: Elements of Chemical Reaction Engineering, 3rdEd. Prentice Hall. Pp 426 477; X: Conversion,</p><p>T: Temperature; EB: Energy balance; MB: Mole balance.</p><p>Algorithm</p><p>1. Design equation</p><p>2. Rate law</p><p>3. Stoichiometry</p><p>4. Combining</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 15/34</p><p>Properties &amp; Equations</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 16/34Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Thermodynamic Properties</p><p>The thermodynamic properties required for the manyfluids handled in the process industries include:</p><p>Densities</p><p>Vapor pressures</p><p>Critical state</p><p>Fugacities</p><p>Entropies</p><p>Enthalpies</p><p>Free energies</p><p> Some of these propertiesexperimentally determined Others are computedfrom basicexperimental data</p><p>thermodynamicequations.</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 17/34Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Some Basic Relations in Thermodynamics</p><p>First law:</p><p>Second law:</p><p>Phase equilibrium relations:</p><p>Chemical reaction equilibrium:</p><p> genEflowEWQEt</p><p> genSflowST</p><p>QSt </p><p>iii fff </p><p>GRTlnK</p><p>iv</p><p>0</p><p>i</p><p>i</p><p>f</p><p>f </p><p>K</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 18/34Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Dimensions &amp; Units</p><p>Dimension SI Unit English Unit</p><p>Time second, s</p><p>Distance meter, m</p><p>foot, ft</p><p>(1 ft = 0.3048 m)</p><p>(1 m = 3.28084 ft)</p><p>Mass kilogram, kg</p><p>pound mass, Ibm</p><p>(1 Ibm= 0.4536 kg)</p><p>(1 kg = 2.2046 Ibm</p><p>Temperature Kelvin, k Rankine, R</p><p>T(R) = 1.8T(K)</p><p>Amount of substance gram mole, g molepound mole, Ib mol</p><p>(1 Ib mol = 453.59 g mol)</p><p>Note: Appendix A : Table A.1, Conversion factors </p><p>f f S</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 19/34Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Prefixes for SI Units</p><p>Multiple Prefix Symbol Multiple Prefix Symbol</p><p>1015 femto f 102 hecto h</p><p>1012 pico p 102 kilo k</p><p>109 nano n 106 mega M</p><p>106 micro 109 giga G</p><p>103</p><p>milli m 1012</p><p>tera T</p><p>102 centi c 1015 peta P</p><p>Note: Appendix A : Table A.1, Conversion factors </p><p>M f A &amp; Si</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 20/34Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Measures of Amount &amp; Size</p><p>3 basic measures</p><p> Mass, m(kg)</p><p> Number f moles, n(mol)</p><p> Total volume, Vt(m3)v</p><p>4 derivatives Specific volume,</p><p> Molar volume,</p><p> Specific density,</p><p> Molar density,</p><p> /kgmm</p><p>VV 3</p><p>t</p><p> /molmn</p><p>VV 3</p><p>t</p><p> 3t</p><p>kg/mV</p><p>1</p><p>V</p><p> m</p><p> 3t</p><p>mol/m</p><p>V</p><p>1</p><p>V</p><p> n</p><p>F (N t 2 d L )</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 21/34Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Force(Newton 2ndLaw)</p><p>SI units:</p><p>English units:</p><p>maF </p><p>mag1Fc</p><p>Force(N = kg ms-2), defined as that force</p><p>which accelerates 1 kg mass 1.0 ms</p><p>-2</p><p>Mass(kg)</p><p>Acceleration(ms-2), 1 ms-2= 3.20808 (ft)(s)-2</p><p>The acceleration of gravity a = g = 9.81ms-2</p><p>Force (Ibf), 1 Ibf represents the force that</p><p>accelerates 1 Ibm at a = 32.1740 (ft)(s-2)</p><p>Mass(Ibm)</p><p>Acceleration(ft)(s)-232.1740 (Ibm)(ft)(Ibf)-1(s)-2</p><p>T t</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 22/34</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Temperature</p><p>Temperature scale</p><p>The Celsius Scale : 0C &amp; 100C correspond to the ice point (freezing</p><p>point) &amp; the steam point (boiling point) of pure water</p><p>at standard atmospheric pressure.</p><p>The Fahrenheit scale : T (F) = 1.8T (C) + 32 or T (C) = [T (F)32]5/9</p><p>The Kelvin scale</p><p>(absolute T)</p><p>: T (K) = T (C) + 273.15</p><p>The Rankine scale : T (R) = 1.8 T (K)</p><p>T (R) = T (F) + 459.67</p><p>R l ti hi A T S l</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 23/34</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Relationship Among T Scales</p><p>Celsius FahrenheitKelvin RankineSteam point</p><p>Ice point</p><p>Absolute zero</p><p>P</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 24/34</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Pressure</p><p>Defined as the normal force exerted by a fluid on a</p><p>surface per unit area of the surface.</p><p>SI units : N/m2= Pascal (Pa)</p><p>English units : (lbf)/(in)2= pound force per square inch (psi).</p><p>1 psi = 6894.8 Pa</p><p>1 atm = 101325 Pa</p><p>1 atm = 14.7 psi</p><p>M t M th d </p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 25/34</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Measurement MethodDead-Weight Gauge Manometer</p><p>To pressuresource</p><p>h</p><p>Weight</p><p>PanPiston</p><p>Cylinder</p><p>Oil</p><p>To pressure</p><p>source</p><p>A</p><p>mg</p><p>A</p><p>FP </p><p> gh</p><p>A</p><p>gAh</p><p>A</p><p>mg</p><p>A</p><p>FP </p><p>m-the mass of the piston, pan and weights;</p><p>g- the local acceleration of gravity;</p><p>A- the cross-sectional area of the piston.</p><p>h- the relative height of the fluid;</p><p>- the fluid density;</p><p>g- the local acceleration of gravity.</p><p>P (C t )</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 26/34</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Pressure (Cont.)</p><p>Gauge Pressure vs. Absolute Pressure</p><p>Different SI units for Pressure</p><p>Readings from most pressure gauges and the manometers correspondto gauge pressures which are the difference between the pressure of</p><p>interest and the pressure of the surrounding atmosphere.</p><p>P (absolute) = P (gauge) + P (barometric)</p><p>1 kPa = 103Pa</p><p>1 MPa = 106Pa</p><p>1 torr = 1 mm Hg = 133.32 Pa</p><p>1 atm = 101325 Pa</p><p>= 101.325 kPa = 0.101325 MPa</p><p>= 760 mm Hg = 760 torr</p><p>= 14.7 psi</p><p>1 bar = 105Pa = 0.986923 atm </p><p>W k</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 27/34</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Work</p><p>Push-Pull Work</p><p>dlFdW </p><p>SI units : Joule (J), 1 J = 1 N m = 1 Pa. m3</p><p>English units : (Ibf)(ft), 1 (Ibf)(ft) = (4.4482 N)(0.3048) =1.3558 J</p><p>2</p><p>1</p><p>l</p><p>lFdlW</p><p>Work done by the force Fover the distance of (l2l1)</p><p>Sign of the work:</p><p> +ve when the displacement d l is in the same direction as the</p><p>applied force.</p><p> -ve when they are in opposite directions.</p><p>W k (C t )</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 28/34</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Work (Cont.)</p><p>PV Work</p><p> tt</p><p>pdVA</p><p>VdPAdlFdW </p><p>2</p><p>1</p><p>V</p><p>V</p><p>tPdVW</p><p>Sign of the work:</p><p> +ve for compression</p><p> -ve for expansion.</p><p>C l l ti f PV W k</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 29/34</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Calculation of PV Work</p><p>Graphical method</p><p>2</p><p>1</p><p>V</p><p>V</p><p>tPdVWRelationshipbetweenP and V</p><p>AreaW </p><p>E</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 30/34</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Energy</p><p>Energy is something that a body can store, and</p><p>which it can receive or give away as workor heat.</p><p>Thus, energy, workand heatare closely related.</p><p>Work and heat are energy in transit, and are</p><p>never regarded as residing in a body.</p><p>Energy, work and heat have the same units:</p><p>Joule (SI)or lb ft (English)</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 31/34 </p><p>P t ti l E (E )</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 32/34</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Potential Energy (EP)</p><p>Consider a body of mass m, acted upon by a force F =</p><p>mg, is raised from position z = z1to z = z2.</p><p>The total work done by theF is</p><p> p</p><p>z</p><p>z</p><p>z</p><p>z</p><p>E</p><p>mgzmgzmgzdlmgFdlW</p><p>12</p><p>2</p><p>1</p><p>2</p><p>1</p><p>SI system : EPmgz Units of Joule or N.m or kgm2s-2English system : Epmgz/gc Units of (Ibf)(ft),</p><p>where gc= 32.1740 (Ibm)(ft)(Ibf)-1(s)-2</p><p>Energ Conser ation</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 33/34</p><p>Chemical Reaction Engineeri ng Group, Universiti Teknologi Malaysia</p><p>Energy ConservationConsider a body of mass m, falls freely from position z</p><p>= z1to z = z2, where the body gains in velocity u1u2.</p><p> 2121</p><p>2</p><p>1</p><p>2</p><p>2</p><p>22</p><p>mgzmgzzzmgFlWmumu</p><p>EK </p><p>In this process, the body gains in kinetic energy is</p><p>the work done by the force of gravity, i.e.,</p><p>While in this process, the change in the bodys</p><p>potential energy is EP= (mgz) = (mgz2mgz1)</p><p>Thus, EK+ E</p><p>P= (mgz</p><p>1mg</p><p>2) + (mgz</p><p>2mgz</p><p>1)</p><p>Therefore, for purely mechanical processes without</p><p>friction, the energy conserves, i.e.,</p><p>0 KK EE 22</p><p>2</p><p>1</p><p>2</p><p>1</p><p>22mgz</p><p>mumgz</p><p>muor</p><p>Heat</p></li><li><p>8/12/2019 01 Chapter 01 (Compiled)</p><p> 34/34</p><p>HeatHeat (Q) always transfers from a high temp. body to a lower temp. one.</p><p>The rate of heat transfer ( ) is proportional to the temp. difference T</p><p>Like work, heat exists only as energy in transitfrom one body to another</p><p>or between a system and its surroundings.</p><p>When energy in the form of heat is added to a system, this part of</p><p>energy is stored NOT as heat, but as kinetic and potential energy of</p><p>atoms/molecules in the system.</p><p>Q</p><p>Units of heat</p><p>SI system : Joule (J)Calorie (Cal), 1 Cal = 4.184 J</p><p>British system : (Ibf)(ft), 1 (Ibf)(ft) = 1.3558 J</p><p>British thermal Unit (Btu), 1 (Btu) = 1055.04 J</p></li></ul>