Madhurig: Created page with "'''Title: Define a Kinetic Reaction''' '''Author: Priyam Nayak''' '''Keywords''': DWSIM , Material stream, simulation, compounds, thermodynamic package, unit systems, plug..."

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Created page with "'''Title: Define a Kinetic Reaction''' '''Author: Priyam Nayak''' '''Keywords''': DWSIM , Material stream, simulation, compounds, thermodynamic package, unit systems, plug..."

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'''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.

{| border=1
|-
|| 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 <nowiki>= k</nowiki>fCN-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 <nowiki>= k</nowiki>f0 exp(<math>\frac{-Ef}{\mathit{RT}}</math>)

Kf0 <nowiki>= 2.94 </nowiki><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 <nowiki>= k</nowiki>b0 exp(<math>\frac{-Eb}{\mathit{RT}}</math>)

Kb0 <nowiki>= 1.176 </nowiki><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 <nowiki>= KC</nowiki>ethyleneoxide kmol/m3.h

C is the molar concentration in mol/m3

K <nowiki>= k</nowiki>0 exp(<math>\frac{-E}{\mathit{RT}}</math>)

k0 <nowiki>= 32324</nowiki>

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.
|-
|}

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

Madhurig: Created page with "'''Title: Define a Kinetic Reaction''' '''Author: Priyam Nayak''' '''Keywords''': DWSIM , Material stream, simulation, compounds, thermodynamic package, unit systems, plug..."