Process-Simulation-using-DWSIM/C2/Define-a-Kinetic-Reaction/English

Title: Define a Kinetic Reaction

Author: Priyam Nayak

Keywords: DWSIM , Material stream, simulation, compounds, thermodynamic package, unit systems, plug flow reactor, kinetic reaction, stoichiometry, reaction order, video tutorial.

Visual Cue	Narration
Slide Number 1 Title Slide	Welcome to this Spoken tutorial on Define a Kinetic Reaction in DWSIM.
Slide Number 2 Learning Objective	In this tutorial, we will learn to: Specify the order of a reaction using Arrhenius rate equation Define the reaction phase Specify rate constants for direct and reverse reactions using Arrhenius equation Specify units for reaction rate
Slide Number 3 System Requirements To record this tutorial, I am using DWSIM 9.0.4 and Windows 11 The process demonstrated in this tutorial is identical in other OS like Linux, Mac OS X or FOSSEE OS on ARM. But, this process is identical in Linux, Mac OS X, or FOSSEE OS on ARM.	This tutorial is recorded using the following setup. The process demonstrated in this tutorial is identical in other OS as well.
Slide Number 4 Pre-requisites To practice this tutorial, you should know to Add components to a flowsheet. Select thermodynamic packages	To practice this tutorial, you should know the following.
Slide Number 5 Add the kinetic rate equation for liquid phase isomerization of n-butane Components present in the system are n-Butane, isopentane and isobutane Reaction: n-C4H10 ⇌ iso-C4H10 Use Peng-Robinson property package	Let us add the kinetic rate equation for liquid phase isomerization of n-butane. Components present in the system are n-Butane, isopentane and isobutane. The reaction is: n-butane isomerizes to form isobutane. Use the Peng-Robinson property package.
Slide Number 6 Reaction Kinetics rate = kfCN-butane - kbCIsobutane kmol / m3 s where C is the molar concentration of respective components in kmol/m3 kf is the forward rate constant kb is the backward rate constant	The reaction rate is as given. Where C is the molar concentration of respective components in kilomol per meter cube kf is the forward rate constant kb is the backward rate constant
Slide Number 7 Forward Reaction Rate Constant kf = kf0 exp(<math>\frac{-Ef}{\mathit{RT}}</math>) Kf0 = 2.94 <math>\times </math>107 Ef = 65300 J/mol	These are the parameters for the forward reaction using the Arrhenius rate equation.
Slide Number 8 Backward Reaction Rate Constant kb = kb0 exp(<math>\frac{-Eb}{\mathit{RT}}</math>) Kb0 = 1.176 <math>\times </math>108 Eb = 72200 J/mol	These are the parameters for the backward reaction following the Arrhenius rate equation.
Switch to DWSIM.	I have opened the DWSIM interface.
Add the compounds N-butane, Isobutane, Isopentane Property package - Peng-Robinson property package. System of Units C5	I have completed configuring the simulation. I have, Added the compounds as n-butane, isobutane and isopentane Selected Peng-Robinson property package and Selected system of units as C5
	Now we will define the Kinetic Reaction.
Highlight Settings in toolbar area Click Settings	Click on the Settings button in the toolbar. The Settings window opens.
Click on Reactions tab	Go to the Reactions tab.
Chemical Reactions >> Add Reaction	Under Chemical Reactions section, click on the green coloured Add Reaction button.
Click on Kinetic	Then click on Kinetic.
Point to Add New Kinetic Reaction	Add New Kinetic Reaction window opens.
Identification >> Name >> Butane Isomerization	First part is Identification. Under Identification, enter the Name as Butane Isomerization.
Description >> Liquid Phase Isomerization of N-butane	Next, enter the Description as Liquid Phase Isomerization of N-butane
Point to Components, Stoichiometry and Reaction Orders	The next part is a table of Components, Stoichiometry and Reaction Orders.
Point to Name field	First column Name, shows the available components here.
Point to Molar Weight	The second column corresponds to its Molar Weight.
Point to ΔHf (kJ/kg)	The third column corresponds to the heat of formation of the components.
Point to Include	The next column is Include. It indicates the components that will take part in the reaction. Under Include, check the check boxes against the components N-butane and Isobutane. Isopentane is inert here and doesn’t participate in the reaction.
Point to BC Tick N-butane	The fifth column is Base Component. Under Base Component, check the N-butane check box as N-butane is the base component.
Point to Stoich. Coeff.	The next column is Stoichiometric Coefficients.
Stoich. Coeff >> N-butane: -1, Isobutane: 1	Under Stoichiometric Coefficients column, enter: -1 for N-butane and 1 for Isobutane. Then press Enter. A negative sign is to indicate the components as Reactants.
Point to Stoichiometry field	In the Stoichiometry field, we can see it is showing OK. So the reaction is balanced after entering the stoichiometric coefficients.
Point to Equation field	Here the Equation field shows the reaction equation.
Point to DO DO >> N-butane: 1 Press Enter.	The next column is DO, which indicates direct/forward reaction order. We are considering the reaction to be First order with respect to N-butane. So we will enter 1 in the DO column against N-butane. And then press Enter.
Point to RO RO >> Isobutane: 1	Next column is RO, which indicates reverse/backward reaction order. We are considering the reaction to be First order with respect to Isobutane. So we will enter 1 in the RO column against Isobutane. And then press Enter.
Point to Kinetic Reactions Parameters	Then comes Kinetic Reactions Parameters.
Basis >> Molar Concentrations	The given rate is in terms of molar concentration. So, we will select Basis as Molar Concentrations.
Phase >> Liquid	Select Phase as Liquid.
Point to Tmin and Tmax	Next is Tmin and Tmax. It gives a temperature range within which rate expression is assumed to be valid.
Tmin (K) >> 0 Tmax (K) >> 2000	Since these values are not given in the problem statement, we will leave them as default values.
Point to Rate Constants for Direct and Reverse Reactions (k and k’)	Now go to Rate Constants for Direct and Reverse Reactions (k and k’).
Point to Direct Reaction Direct Reaction >> Arrhenius	Now, we will provide kinetic parameters for forward/direct reaction. First is to select the type of rate law. From the problem statement, it can be seen that Arrhenius Rate Law is followed. By default, Arrhenius is already selected. So let’s not change it.
A >> 2.94E+7	Next is to enter the value of A which is the pre-exponential factor. As per the problem statement, the pre-exponential factor is 2.94E7, so type 2.94E+7 in A.
E >> 65300	Next is E which is the Activation Energy. Against E, type 65300.
Point to the units beside E	Next is to indicate the units of Activation Energy, E. As per the problem statement, given value of Activation Energy is in J/mol. It is the default unit, so we will not change anything.
Point to Reverse Reaction	Next we will provide kinetic parameters for reverse/backward reaction.
Reverse Reaction >> Arrhenius	First is to select the type of rate law. Similar to the forward reaction, it can be seen that Arrhenius Rate Law is followed also for the backward reaction. By default, Arrhenius is already selected. So let’s not change it.
A >> 1.176E+8	Next is to enter the value of A which is the pre-exponential factor. As per the problem statement, the pre-exponential factor is 1.176E8, so type 1.176E+8 in A'
E >> 72200	Next is E which is the Activation Energy. Against E, type 72200.
Point to the units beside E	Next is to indicate the units of Activation Energy, E’. As per the problem statement, given value of Activation Energy is in J/mol. It is the default unit, so we will not change anything.
Point to Amount Units	Now, we will select Amount Units. This is to indicate the units of Basis term selected in the Kinetic Reaction Parameters. Here, Molar Concentrations is selected as Basis under Kinetic Reaction Parameters. As per the problem statement, the units of Molar Concentration are mentioned as kmol/m3.
Amount Units >> kmol/m3 Click on the drop-down against Amount Units >> select kilomol per meter cube if not already selected.	By default, kilomol per meter cube is already selected as an Amount Unit. So, let’s not change it.
Demonstration >> Of changing Basis Units Click >> Basis >> Partial Pressure Amount Units >> Click on drop-down to show pressure units.	If the rate is defined using partial pressure, choose Partial Pressure as the Basis instead of Molar Concentration. Select the unit in which partial pressure is expressed in the rate equation. You can see that the drop-down against Amount Units shows the units of pressure.
Basis >> Molar Concentrations Amount Units >> kmol/m3	Let us go back to the original Basis. Change the Basis to Molar Concentrations. Ensure that the Amount Units is kmol/m3.
Point to Rate Units Rate Units >> kmol/[m3.s]	So we have to select the rate units. According to our question, the rate units are kilomol per meter cube second. Click on the drop-down against Rate Units and select kilomol per meter cube second. It is important to select the correct unit.
Click on OK	Click on OK.
Close the Settings window.	Now that the reaction is added, close the Settings window.
	In the next tutorial, we will use the added reaction to simulate a Plug Flow Reactor.
File >> Save As >> kinetic-reaction	Let us save the file as kinetic-reaction.
Slide Number 8 Summary Specify the order of a reaction using Arrhenius rate equation Define the reaction phase Specify rate constants for direct and reverse reactions using Arrhenius equation Specify units for reaction rate	With this we come to the end of this tutorial. Let us summarize.
Slide Number 9 Assignment Compounds: Ethylene oxide, Water & Ethylene glycol Reaction: C2H4O + H2O ⇌ C2H6O2 Property Package: NRTL Reaction Rate: r A = KCethyleneoxide kmol/m3.h C is the molar concentration in mol/m3 K = k0 exp(<math>\frac{-E}{\mathit{RT}}</math>) k0 = 32324 E = 45584 J/mol	As an assignment, add the following kinetic equation.
Slide Number 10 DWSIM Flowsheeting Project	We invite you to participate in DWSIM Flowsheeting Project.
Slide Number 11 Lab Migration Project	We invite you to migrate commercial simulator labs to DWSIM.
Slide Number 12 Acknowledgements	The FOSSEE project is funded by NMEICT, Ministry of Education(MoE), Government of India.
Slide Number 13 Thanks	We thank the DWSIM team for making it as an open source software. Thank you for joining.

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