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|10.07 - Nonideal Systems||Click here.||100||1||
Nonideal Mixtures (4:58) (msu.edu)
Raoult's law is an easy way to calculate VLE, but it is inaccurate for most detailed VLE calculations. This screencast provides an overview of the problems, and introduces the concept of an azeotrope. The VLE K-ratio is shown to be less than one or greater than one dependenting on the overall system concentration relative to the azeotrope composition where K=1. The concept of positive and negative deviations is introduced.
|01.5 Real Fluids and Tabulated Properties||Click here.||100||1||
|10.06 - Relating VLE to Distillation||Click here.||100||2||
Distillation is the primary choice for separations in the petrochemical industry. Because the majority of chemical processing involves separations/purifications, that makes distillation the biggest economic driver in all of chemical production. Therefore, it is very important for chemical engineers to understand how distillation works (21min, uakron.edu) and how VLE plays the major role. This video is a bit long, but it puts into context how phase diagrams and thermodynamic properties relate to very important practical applications. You may find it helpful to reinforce the conceptual video with some sample calculations.(12min) At the end of the video, you should be able to answer the following:
Consider the acetone+ethanol system. Use SCVP (Eqn 2.47) to answer the following.
|01.6 Summary||Click here.||100||1||
The objectives for Chapter 1 were:
1. Explain the definitions and relations between temperature, molecular kinetic energy,
To these, we could add expressing and explaining the first and second laws. Make a quick list of these expressions and explanations in your own words, including cartoons or illustrations as you see fit, starting with the first and second laws.
|10.08 - Concepts for Generalized Phase Equilibria||Click here.||100||1||
When expressing the derivative of the total Gibbs energy by chain rule, there is one particular partial derivative that relates to each component in the mixture: the "chemical potential." By adapting the derivation from Chapter 9 of the equilibrium constraint for pure fluids, we can show that the equilibrium constraint for mixtures is that the chemical potential of each component in each phase must be equal. That is fine mathematically but it is not very intuitive. By translating the chemical potential into a rigorous definition of fugacity of a component in a mixture, we recognize that an equivalent equilibrium constraint is that the fugacity of each component in each phase must be equal. (8min, Live, uakron.edu) This offers the intuitive perspective of, say, molecules from the liquid escaping to the vapor and molecules from the vapor escaping to the liquid; when the "escaping tendencies" are equal, the phases experience no net change and we call that equilibrium.
|11.02 - Calculations with Activity Coefficients||Click here.||96||5||
Dew Temperature (7:57) (msu.edu)
The culmination of the activity coefficient method is application of the fitted activity coefficients to extrapolate from limited experiments in a Stage III calculation. The recommended order of study is 1) Bubble Pressure; 2) Bubble Temperature; 3) Dew Pressure; 4) Dew Temperature. Note that an entire Txy diagram can be generated with bubble temperature calculations; no dew calculations are required. However, many applications require dew calculations, so they cannot be avoided. The dew calculations are more complicated than bubble calculations, because the liquid activity coefficients are not known until the unknown liquid mole fractions are found. This screencast describes the procedure and how to implement the method in Matlab or Excel.
|10.01 - Introduction to Phase Diagrams||Click here.||96||5||
Introduction to Phase Behavior (9:37) (msu.edu)
1. Referring to the Txy diagram on slide 3, estimate T, nature (ie. L,V, V+L, L+L), composition(s), and amount of the phase(s) for points: a, b. d, g.
|14.10 Solid-liquid Equilibria||Click here.||95||4||
SLE using Excel with the M1 model (7min, uakron.edu)
Similar to LLE in Excel, the iteration feature can be used to quickly solve for SLE at multiple temperatures.
|07.06 Solving The Cubic EOS for Z||Click here.||95||4||
1. Peng-Robinson PVT Properties - Excel (3:30) (msu.edu)
Introduction to PVT calculations using the Peng-Robinson workbook Preos.xlsx. Includes hints on changing the fluid and determining stable roots.
1. At 180K, what value of pressure gives you the minimum value for Z of methane? Hint: don't call solver.
2. At 30 bar, what value of pressure gives Z=0.95 for methane?
3. Compute the molar volume(s) (cm3/mol) for argon at 100K for each of the following?
|04.09 Turbine calculations||Click here.||93.3333||3||
General procedure to solve for steam turbine efficiency. (LearnChemE.com, 5min) This video outlines the procedure without actually solving any specific problem. It shows how inefficiency affects the T-S diagram and how to compute the actual temperature at the turbine outlet.