application of thermodynamics and molecular simulation in chemical engineering problems
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Application ofthermodynamics and
Molecular simulation in Green Separation processDr.R.Anantharaj
Department of Chemical Engineering
National Institute of Technology Tiruchirappalli
Tiruchirappalli-620015
Tamil NaduINDI!
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My Home
GreenSolvent
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Over view
Introduction "olecular #imulation Constituent
Ionic $i%uids
#eparation Techni%ues
!pplications
#ummary
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What is thermodynamics?
Thermo = energy
Dynamics = motion
Thermodynamics = the motion of energy
Thermodynamics = the comparison of states to determine
their relative stability.
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Denition of a “state” in terms ofenery
!"Σ#e$ i%epi&
'inetic enery
(otential enery
)nternal enery*
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Why st+dy thermodynamics in ,hemical
-nineerin?
Thermodynamics is the basis for understanding a chemical response to changes in
temperature, pressure, and composition. Thus the critical link between processing
and microstructure requires a knowledge of the relevant thermodynamics principles.
(roperties
(rocessin
Str+ct+re
Atomic,rystal . Molec+lar
Grain str+ct+re(hase distri/+tion
DefectsMechanica
l,hemical-lectrical
Manetic0hermal
0emperat+re(ress+re . stress 1ol+me . strain
,hemical composition
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Why Molec+lar sim+lation2? "olecular simulation is primarily a tool for
calculating the energy of a gi&en molecular
structure'
To define the chemical engineering pro(lem
)ell as one in&ol&ing a structure-energyrelationship'
Identifying correlations (et)een chemical
structures and properties #toring and searching for data on chemical
entities
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Molec+lar Sim+lation2?
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Di3erence 4etween MS 5 -6
"olecular #imulation E,perimentE,periment"olecular #imulation E,periment
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Molec+lar Sim+lation,onstit+ent Molecular Mechanics (MM) a chemist3s
model It3s descri(es the energy of a molecule in terms
of a simple function which accounts for deformation from
“ideal” (ond distances and angles as )ell as and for
non(onded &an der 4aals and Coulom(ic interactions'
Quantum Mechanics (QM) a physicist3s
model It3s descri(es the energy of a molecule in terms
of interactions among nuclei and electrons as given by
the Schrödinger equation'
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Schematic Diaram of MM
∑∑∑ ++=anglesdihedral
anglesbonds
twisting dihedral bending angle stretcing bond E 1
∑∑ +=atomsof
Pairsatomsof
Pairs
forceCoulombic forceWaalsder Van E 2
21 E E E += 21 E E E += 21 E E E +=
∑∑∑ ++=ang lesdihedral
anglesbonds
twisting dihedral bending angle stretcing bond E 1
21 E E E +=
∑∑ +=atomsof
Pairsatomsof
Pairs
forceCoulombic forceWaalsder Van E 2
∑∑∑ ++=anglesdihedral
anglesbonds
twisting dihedral bending angle stretcing bond E 1
21 E E E +=
∑∑ +=atomsof
Pairsatomsof
Pairs
forceCoulombic forceWaalsder Van E 2
∑∑∑ ++=ang lesdihedral
anglesbonds
twisting dihedral bending angle stretcing bond E 1
21 E E E +=
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Limitations of Molecular Mechanics
MM Description Basedon the Bonding
Pattern of Product
MM Description Basedon the Bonding
Pattern of Reactant
Correct description
The bond-breaking and bond-forming cannot be described.
A B C A B C
Reactant Product
A B C
Transition State
Progress of Reaction
nerg!
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Quantum Mechanics
(QM)
The #chrdinger e%uation plays the role ofNe)tons la)s and conser&ation of energy inclassical mechanics
It is a )a&e e%uation in terms of the )a&e
function )hich predicts analytically andprecisely the pro(a(ility of e&ents oroutcome'
The #chrdinger e%uation gi&es the%uanti.ed energies of the system and gi&esthe form of the )a&e function so that otherproperties may (e calculated'
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Schr7diner -8+ation
Computational Chemistry 5510
Spring 2006 Hai Lin
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"uantum Mechanics
MacroscopicMicroscopic
Quantum mechanics is the law governing the behavior of nuclei and electrons.
Energy
Internuclear
DistanceO
H
H
!".#$ Correct Descri%tion
for Bond&brea'ing
and Bond&forming
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Basis of "uantum Chemistr!
Schr#dinger e$uation%
HHψ ψ "" E Eψ ψ
Erwin (chr)dinger *aul A. +. Dirac
Nobel Prize in Physics1933
"or the !iscovery o ne#ro!uctive orms o
atomic theory"
Dirac &'()(*% +The underl!ing ph!sical
la,s necessar! for the mathematical
theor! of a large part of ph!sics and
the ,hole of chemistr! are thus
completel! kno,n.
o,e/er0 it can be sol/ed e1actl! onl! for one-electron s!stems &e.g.0 a
h!drogen atom* and numericall! for an! a s!stem ha/ing more electrons.
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2ccurate "uantum Mechanical Methods
2ccurate $uantum mechanical computation is a po,erful tool in stud! ofchemistr! 3 chemical engineering .
,obel *ri-e inChemistry /
4alter 5ohn 6ohn 2. Pople
+for his de/elopment of the
densit!-functional theor!
+for his de/elopment of
computational methods in
$uantum chemistr!
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Schr#dinger $uation
2
n
n
2
1a
N
a a M ∇−= ∑T
∑∇−=
e N
i
i
m
2
e
e
2
1T
Kinetic energy of nuclei
Kinetic energy of electrons
Coulombic energy between nuclei
Coulombic energy between electrons
Coulombic energy between nuclei and electrons
H Tn ! Te ! Vnn ! Vee ! Vne
n9 n:
e9 e:
∑∑>
=n n
nn
N
a
N
ab ab
ba
r
Z Z V
∑∑>=e e 1
ee
N
i
N
ji ijr V
∑∑=n e
ne
N
a
N
i ai
a
r
Z V
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2ppro1imations
To solve the "chr#dinger equation appro$imately, assumptionsare made to simplify the equation%
&Born-Oppenheimer approximation allows separate
treatment of nuclei and electrons. 'ma (( me)
&Hartree-o!" in#epen#ent ele!tron approximation
allows each electron to be considered as being affected by
the sum 'field) of all other electrons.
&LC$O $pproximation represents molecular orbitals as
linear combinations of atomic orbitals 'basis functions).
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Born-7ppenheimer 2ppro1imation
& *uclei are much heavier than electrons 'ma + me ≥ 1-) andmove much slower.
&/ffectively, electrons ad0ust themselves instantaneously to
nuclear configurations.
&/lectron and nuclear motions are uncoupled, thus the energies
of the two are separable.
Energy
Internuclea
r Distance
9; oint toform a potential enery
s+rface on which n+cleimove;
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Man!-electron 4a/e function
%
e9
e:
e N
ei
Pauli #rinci#le& 0wo electrons can not have all8+ant+m n+m/er e8+al;
This requires that the total 'manyelectron) wave function
is antisymmetric whenever one e$changes two electrons
coordinates.
φ i' x 1) φ j' x 1) 3 φ k ' x 1)
φ i' x 2) φ j' x 2) 3 φ k ' x 2)
φ i' x N ) φ j' x N ) 3 φ k ' x N )
Ψ' x 1, x 2, 3, x N ) '1+ N 4)5
Hartree #ro!uct& All electrons are independent= each in itsown or/ital;Ψ67' x 1, x 2, 3, x N ) φ i' x 1) φ j' x 2)3
φ k ' x N )
Ψ' x 1, x 2, 3, x N ) − Ψ' x 2, x 1, 3, x N )
Slater !eterminant satises the (a+li principle;
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Man!-electron 4a/e function &)*
e9e:
The total 'manyelectron) wavefuntion is antisymmetric when one
e$changes two electrons coordinates x 1 and x 2.
φ i' x 1) φ j' x 1)
φ i' x 2) φ j' x 2)Ψ' x 1, x 2) '1+2)5
Hartree #ro!uct& 4oth electrons areindependent;Ψ67' x 1, x 2) φ i' x 1) φ j' x 2)
Ψ' x 2, x 1) '1+2)5 8φ i' x 2) φ j' x 1) − φ i' x 1) φ j' x 2)9 − Ψ' x 1, x 2)
Slater !eterminant satises the (a+li principle;
-@ample* A twoelectron system;
Ψ' x 1, x 2) '1+2)5 8φ i' x 1) φ j' x 2) − φ i' x 2) φ j' x 1)9
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artree-8ock 2ppro1imation
%
&: ;ock operator is introduced for a given electron in the ith orbital%
i
φ i
ε i
φ i
$inetic eneryterm of the
iven electron
potentialenery termd+e to @ed
n+cleiaveraed
potentialenery termd+e to the
other electrons
i %
φ i is the ith molecular orbital, and ε i is the corresponding orbital energy.
*ote% The total energy is *feels? all the other electrons as a whole 'field
of charge), .i.e., an electron moves in a meanfield generated by all the other electrons.
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The 8ock 7perator
Kinetic energy term
and nuclear attraction
for the given electron
∑ −+= N
j
j jii )' % &h
,oreHamiltonian
operator
,o+lom/
operator
-@chane
operator
Coulombic energy
term for the given
electron due to
another electron
/$change energy due
to another electron
': pure quantum
mechanical term due tothe 7auli principle, no
classical interpretation)
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Self-consistenc!
&The ;ock equation for an electron in
the ith orbital contains information ofall the other electrons 'in an averaged
fashion), i.e., the ;ock equations for all
electrons are coupled with each other.
e jek
ei
&/ach electron >feels? all the other electrons as a whole 'field of
charge), .i.e., an electron moves in a meanfield generated byall the other electrons.
&:ll equations must be solved together
'iteratively until selfconsistency is obtained).
@ "elfconsistent field '"C;) method.
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Refresh 9our Mind%
igen/alue 3 igen/ectorAenerally, one can construct a matri$ for an operator, e.g., the6amiltonian H' using a set of basis functions Bφ i.
φ 1 φ 2 ... φ nφ 1φ 2... φ n
H 99 H 9: ;;; H 9n
H :9 H :: ;;; H :n
H n9 H n: ;;; H nn:fter diagonaliDation, one obtains eigenvalues 'energy levels)
and eigenvectors 'wavefunctions).
Where H ij " 〈φ i B H B φ j〉
" ∫ φ i*# x & H# x & φ j # x & d x
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Linear Combination of 2tomic 7rbitals
&/ach oneelectron molecular orbital is appro$imated by a linear combination
of atomic orbitals 'basis functions).
φ c1 χ1 ! c2 χ2 ! c- χ- ! 3
where φ is the molecular orbital wavefunction, χi represents atomic orbitalwavefunction, and ci is the corresponding e$pansion coefficients.
&The resulting ;ock equations are called Eoothaan6all equations.
&This reduces the problem of finding the best functional form for the
molecular orbitals to the much simpler one of optimiDing a set of coefficients
'cn) in a linear equation.
x
y
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:ariational Principle
Fased on the GC:< appro$imation, each oneelectron molecular
orbital is appro$imated as a linear combination of atomic orbitals.
φ c1 χ1 ! c2 χ2 ! c- χ- ! 3
&The energy calculated from any appro$imated wave function ishigher than the true energy.
&The better the wave function, the lower the energy.
&
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functionwaetheis
energy !otential energykineticenergytotal theis E
o!erator nhamiltoniatheis "
where
i −
+−
−
ψ
)'
%
2
2
22
22
2
1
26/quationIdinger"chr
2
1
2
%
kx xm
o
xi
!
kxm
!energyof onConserati
#uantum
+∂∂−
=∂
∂=
+=
functionwaetheis
energy !otential energykineticenergytotal theis E
o!erator nhamiltoniatheis "
where
i −
+−
−
ψ
)'
%ii E " ψ ψ =
functionwaetheis
energy !otential energykineticenergytotal theis E
o!erator nhamiltoniatheis "
where
i −
+−
−
ψ
)'
%
µ
µ
µ φ ψ ∑=
=n
ii C 1
ii E " ψ ψ =
functionwaetheis
energy !otential energykineticenergytotal theis E
o!erator nhamiltoniatheis "
where
i −
+−
−
ψ
)'
%
2
2
22
22
2
1
26/quationIdinger"chr
2
1
2
%
kx xm
o
xi
!
kxm
!energyof onConserati
#uantum
+∂∂−
=∂
∂=
+=
µ
µ
µ φ ψ ∑=
=n
ii C 1
2
2
22
22
2
1
26/quationIdinger"chr
2
1
2
%
kx xm
o
xi
!
kxm
!energyof onConserati
#uantum
+∂∂−
=∂
∂=
+=
functionwaetheis
energy !otential energykineticenergytotal theis E
o!erator nhamiltoniatheis "
where
i −
+−
−
ψ
)'
%
µ
µ
µ φ ψ ∑=
=n
ii C 1
2
2
22
22
2
1
26/quationIdinger"chr
2
1
2
%
kx xm
o
xi
!
kxm
!energyof onConserati
#uantum
+∂∂−
=∂
∂=
+=
kxma $ law Newtons
kxmenergyof onConserati
Classical
−==
+=
I
2
1
2
1
%
22
ii E " ψ ψ =
ErwinSchrödinger,
1927
2
2
22
22
2
1
26/quationIdinger"chr
2
1
2
%
kx xm
o
xi
!
kxm
!energyof onConserati
#uantum
+∂∂−
=∂
∂=
+=
kxma $ law Newtons
kxmenergyof onConserati
Classical
−==
+=
I
2
1
2
1
%
22
µ
µ
µ φ ψ ∑=
=n
ii C 1
2
2
22
22
2
1
26/quationIdinger"chr
2
1
2
%
kx xm
o
xi
!
kxm
!energyof onConserati
#uantum
+∂∂−
=∂
∂=
+=
kxma $ law Newtons
kxmenergyof onConserati
Classical
−==
+=
I
2
1
2
1
%
22
functionwaetheis
energy !otential energykineticenergytotal theis E
o!erator nhamiltoniatheis "
where
i −
+−
−
ψ
)'
%
µ
µ
µ φ ψ ∑=
=n
ii C 1
2
2
22
22
2
1
26/quationIdinger"chr
2
1
2
%
kx xm
o
xi
!
kxm
!energyof onConserati
#uantum
+∂∂−
=∂
∂=
+=
kxma $ law Newtons
kxmenergyof onConserati
Classical
−==
+=
I
2
1
2
1
%
22
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C+ant+m Harmonic Oscillator*Wave f+nction
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C+ant+m ,hemical Map
7
8 8 8 8
7
M% &% 'C&% →
CHEMICAL
ENGINEERDECIDES
COMPUTER CALCULATES
#tartingmoleculargeometry
9asis set : 9asisfunction
Type of
Calculation
;roperties to (ecalculated
7
8 8 8 8
7
M% &% 'C&% →
7
8 8 8 8
7
M% &% 'C&% → M% &% 'C&% →
7
8 8 8 8
7
M% &% 'C&% →
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4asis
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L+ -1 "$ (−
The no of
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Software (ac$aes e8+ired
E,ceed -
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)onic Ei8+ids Ionic li%uids/I$s are organic salts )ith )ide li%uid range and lo)
melting point /?1000Cconsists of organic cation and
organic*inorganic anion
I$s also =no)n as @deigner o!"entA due to their a(ility to &ary
the ions /i'e cation and anion and there(y modifying and optimi.ing
the I$s properties'
I$s are referred to as @green o!"entA due to negligi(le &apour
pressure )hich can reduce the technical e,posure : sol&ent loss to
the en&ironment'
I$s ha&ing high denit# than organic inorganic and )ater
molecules in )hich it may e,ist as a separate phase )hen in contact
)ith aromatic sulphur*nitrogen compounds'
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S'*'+ ,- .,N.* /.Q.0
NN
CH3)
*-
+
12lyl3methylimi!azoliumanion 14utyl3methylimi!aozlium
he5a6uoro#hos#hate
F4M)MF(
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'7P.*2/ *2'.,NS 2N0 2N.,NS .N .,N.*/.Q.0S
*
*
E -
E 1
E K
E M
E 2
*
E .
E -
E M
E 1
E 2
E K
*
E 1
E 2
E -
E M
C$T,O-S $-,O-S
8F;M9
87;.9
Cl+:lCl-
Cl,Fr ,=
*
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Chemical systems of IL’s
April 9:= :I9 State of the art Seminar JI
;ure ionic li%uids
cation anion B I$3s 9inary mi,ture containing I$3s
I$3s "olecular Compounds
Molecular compouns: aliphatic al=anes
cyclohydrocar(ons aromatic hydrocar(onsetc'''!"amples: solu(ility of 72 and C72 in 1-9utyl->-
"ethylimida.olium Tetrafluoro(orate
Ternary mi,ture containing I$3s
I$3s "olecular compound "olecular compound
/or
I$3s I$3s "olecular compound
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Application of ionic li8+id in the f+t+re
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0ypical S+lph+r 5 Kitroencompo+nds#
#
#
NH
NH
NH
HN
N
N
N
Thiophene TS3 Ben4othiophene BTS3 i(en4othiophene BTS3
yrrole 7) 3 ,n#ole ,3 ,n#oline ,O3Car(a4ole C$3
yri#ine 73 8uinoline 893 Ben4ouinoline B893
# #
#
NH
NH
NH
HN
N
N
N
Thiophene TS3 Ben4othiophene BTS3 i(en4othiophene BTS3
yrrole 7) 3 ,n#ole ,3 ,n#oline ,O3Car(a4ole C$3
yri#ine 73 8uinoline 893 Ben4ouinoline B893
i(en4othiophene BTS3
# #
#
NH
NH
NH
HN
N
N
N
Thiophene TS3 Ben4othiophene BTS3
yrrole 7) 3 ,n#ole ,3 ,n#oline ,O3Car(a4ole C$3
yri#ine 73 8uinoline 893 Ben4ouinoline B893
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Ho$ S % N co&'ound can a((ect)*
Di d t f it d l h i
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Disadvantages of nitrogen and sulphur in
Diesel oil
itrogen3 S Sulphur3
Nndesirable. Nndesirable.
Catalyst deactivation . Catalyst deactivation .
Geading to coke formation. Geading to coke formation.
6ighly inhibiting effect on6O".
6ighly inhibiting effect onactive catalyst.
7otentially affect dieselstability during storage.
7otentially affect dieselstability during storage.
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To produce *
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HDN & HDS Limitations
H HS
Consume high energy Consume high energy
"evere operating conditionsT-HHHHQC R 7 J1H S7a
"evere operating conditionsT-HHMHHQC R 7 (M S7a
Gower space velocity Gower space velocity
:dditives are needed toimprove fuel properties and
performance
:dditives are needed toimprove fuel properties and
performance
Gess efficiency for refractorynitrogen. Gess efficiency for refractorysulphur.
e.g.%pyrrole,indoline,pyridine,quinoline.
e.g.% thiophene,benDothiophene.
Si l t d Di l iti
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Simulated Diesel composition
#nti! C$
wt %
C&
wt %
C'
wt %
C9
wt %
C1(
wt %
C11)
wt
%
n*+arans
-Cn.2n)2/
&07 102 (01 20$ * * (0(&
4soparans-Cn.2n)2/
1(09 $0&2 10'1 17 10 * (0
5romatics
-Cn.2n*&/
* (02 &07
1
(0 (0 (0& (0
6aphthenes-Cn.2n/
(0 10&2 101 102 * * *
O!ens
-Cn.2n/
&07 10&2 (0$1 (01 (02 * *
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Separation processes eneral "echanical separations e'g' filtration of a
solid from a suspension in a li%uid
centrifugation screening etc
"ass transfer operations e'g' distillatione,traction etc
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Mass transfer operations Lnat+re of interface /etween
phases
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Mass transfer operations Lcontrollin transport
phenomenon "ass transfer controlling e'g'distillationa(sorption e,traction adsorption etc
"ass transfer and heat transfer controlling
e'g' drying crystallisation 8eat transfer controlling e'g' e&aporation
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Methods of operation
Non steady state concentration changes
)ith time e'g' (atch processes
#teady state
#tage
Differential contact
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When /oth phases areowin* Co-current contact
Cross flo)
Counter-current flo)
Stae 9 Stae :
9 :
9 :
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,hoice of separation process
+actors to (e considered
+easi(ility
;roduct &alue
Cost
;roduct %uality
selecti&ity
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Ei8+idli8+id e@tractionprinciples+eed phase contains a component i )hich is
to (e remo&ed' !ddition of a second phase/sol&ent phase )hich is immisci(le )ith feed
phase (ut component i is solu(le in (othphases' #ome of component i /solute istransferred from the feed phase to the sol&entphase' !fter e,traction the feed and sol&ent
phases are called the raffinate / ande,tract /E phases respecti&ely'
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-@tractants
The efficiency of a li%uid li%uid e,traction can
(e enhanced (y adding one or more
e,tractants to the sol&ent phase' The
e,tractant interacts )ith component iincreasing the capacity of the sol&ent for i'To
reco&er the solute from the e,tract phase the
e,tractant-solute comple, has to (e
degraded'
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Distri/+tion coe3icient
B mass fraction solute in E phase
mass fraction solute in phase
B y*,
$arge &alues are desira(le since less sol&ent is
re%uired for a gi&en degree of e,traction
) i i/l li id
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)mmisci/le li8+ids
e'g' )ater chloroform
Consider a feed of )ater*acetone/solute'
B mass fraction acetone in chloroform phase mass fraction acetone in )ater phase
B =g acetone*=g chloroform B y*,
=g acetone*=g )ater
B 1'2i'e' acetone is preferentially solu(le in the chloroform phase
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( i ll i i/l li id
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(artially misci/le li8+idsE'g' )ater "I9
Consider a solute acetone'
Need to use a triangular phase diagram to sho)
e%uili(rium compositions of "I9-acetone-)ater mi,tures'
Characteristics are single phase and t)o phaseregions tie lines connecting e%uili(rium phasecompositions in t)o phase region'
,h i f l t
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,hoice of solvent+actors to (e considered
#electi&ity Distri(ution coefficient
Insolu(ility of sol&ent
eco&era(ility of solute from sol&ent
Density difference (et)een li%uid phases
Interfacial tension
Chemical reacti&ity
Cost Fiscosity &apour pressure
+lamma(ility to,icity
S l ti it
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Selectivity
G B /mass fraction 9 in E*/mass fraction ! in E
/mass fraction 9 in */mass fraction ! in
G H 1
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( ti
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(roperties*Density: ! density difference is re%uired (et)een
the t)o phases'
$nter%acial tension : The larger the interfacialtension (et)een the t)o phases the more
readily coalescence of emulsions )ill occur togi&e t)o distinct li%uid phases (ut the more
difficult )ill (e the dispersion of one li%uid in the
other to gi&e efficient solute e,traction'
Chemical reacti&ity: #ol&ent should (e sta(le andinert'
(h i l ti
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(hysical properties
+or material handling
$o) &iscosity
$o) &apour pressure
Non-flamma(le /high flash point
Non-to,ic
S ti 0 h i
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Separation 0echni8+es
$i%uid-$i%uid E,traction1';rocess is applica(le at am(ient conditions
2'#pecial e%uipment re%uirements
>'Energy consumption is negligi(le
'No hydrogen consumption
5'8andling is easy
6'The process does not change the chemical
structure of the components'
A li ti f M l l
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Application of Molec+larSim+lation To predict the $J"7 and 87"7 energy of the
molecules and their thermodynamic properties
To find the scalar properties
Chemical potential /K
Electronegati&ity /L
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roperties name :mpiri!al expressionOperational
expressionOr(ital e.inition
Chemical potential ' )
/lectronegativity 'U)
Alobal 6ardness 'V )
Alobal "oftness '")
/lectrophilicity
inde$'W )
Or/ital DenitionsScalar(roperties
' ) r
E
N µ
∂ = ∂ 2
/P E&+ − ÷ 2
"%M% '+M%ξ ξ + ÷
' ) r
E
N χ µ ∂ = ∂
; -
2
/P E&+ ÷ 2
"%M% '+M%ξ ξ + ÷
2
2' ) ' )
1 1
2 2V r r
E
N N
µ η
∂ ∂ = = ∂ ∂ 2 /P E&−
÷ 2
"%M% '+M%ξ ξ − +
÷
2
2' ) ' )
1 1 1
2 2V r r
s E
N N
µ η = = =∂ ∂ ∂ ∂
2 /P E&
÷− 2
"%M% '+M%ξ ξ
÷− +
2
2
µ ω
η = M
/P E&+ ÷ M
"%M% '+M%ξ ξ − +
÷
MOED-K S ft
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MOED-K Software
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(artial ,hares (redictions
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(artial ,hares (redictions'ile !it aitional
section mem=-M> un
Route section ? @35?*+,3--B/ opt=2iis#C'(C4N!R=9MAECC5!=-6) pop(npachelp2)2eom=istance
7=
Title section ?artial char2es
Char2e an multiplicity -
Molecular speci%ication
'or e"ampleF Thiophene optimi1e &alues %rom M45D!N out %ile(a%ter 6ND step)s c - cs6c 6 cc3 - ccs3c 3 cc7 6 ccc7 - ih7
c 7 cc8 3 ccc8 6 ih8h 8 hc+ 7 hcc+ - ih+h 7 hc9 8 hcc9 3 ih9h 3 hc 7 hcc 6 ihh 6 hc; 3 hcc; - ih;cs6 -.9-cc3 -.78ccs3 -;.79-cc7 -.78ccc7 -;.79-ih7 .
cc8 -.78ccc8 -;.79-ih8 .hc+ -.;hcc+ -;.79-ih+ -.hc9 -.;hcc9 -;.79-ih9 -.
(artial ,hares
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(artial ,hares
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(artial ,hares
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(artial ,hares of ,ation#4M(O&
(artial ,hares of
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(artial ,hares of)E#4M(O4
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(artial ,hares of )E%0hiophene
E!MO HOMO -neries
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E!MOHOMO -neries(redictions
)nteraction -neries
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)nteraction -neries(redictions
COSMO RS model
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COSMO-RS model C7#"7-# consist of
- Puantum theory- #urface interactions
- #tatistical thermodynamics
- Dielectric continuum models
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*,SM, & *,n!uctor /ieScreenin8 M,!el
Element #pecific
"olecular Ca&itiesCreated #ol&ent !ccessi(le !rea
/#!#
"olecule ;laced
In a conductor #olute "olecule
"olecule ;ulls Charges
+rom the conductor
To the interface
":" divided into small segments
each having a screening charge
density X
LH :q)otal soluteΦ Φ = = +
#urface Charge Distri(ution #I
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The energy difference (et)een the real situation of such contact and
the ideally screened situation has to (e defined as a local electrostatic
interaction energy )hich results from the contact of the molecules'
PCI!
))))))
σY
σ
σ>> 0σYZZ H 8ydrogen 9onding
Interaction
"isfit Energy
Interaction
IdealElectrostati
c
Contact
I t ti "
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Interaction "ner#yCalculations "isfit interaction
6ydrogen bonding ( )2
' , ) ' , )
2
misfit eff misfit
eff
E a e
a
σ σ σ σ
α σ σ
′ ′=
′′= +
' , ) ' , )
minBH,min'H, )ma$'H, )C
hb eff hb
eff hb don hb acc hb
E a e
a c
σ σ σ σ
σ σ σ σ
′ ′=
= + −
mist constant
.8drogen :onding coecientthresho!d for .8drogen:onding
E;ecti
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$cti%ity Coe&icient
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$cti%ity Coe&icient
!cti&ity Coefficient of the #egment
!cti&ity Coefficient of Component in "i,ture
' , )ln ' ) ln ' ) ' )e$p
* * *
E !
k) σ
σ σ σ σ σ
′
′ − Γ = − Γ ∑
2' , ) ' ) minBH, min'H, ) ma$'H, )C
2 hb don hb acc hb
E cα
σ σ σ σ σ σ σ σ ′
′ ′= + + + −
+ +ln ' )8ln ' ) ' )9 ln *(
i * i i * i i * n !
σ
γ σ σ σ γ = Γ − Γ +∑i
i
eff
&n
a==here
i0e The contri(ution of molecule Ri’ to the surface segment
( )+γ i S 7nce !cti&ity Coefficients is =no)n )e can predict $i%uid $i%uidE%uili(ria /$$E
'eneration of COSMO (ile
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'eneration of COSMO (ile
#tep:-: eometry 4ptimi1ation in as ?hase
5e&el o% Theory ;9FQ6 /Density +unctional Theory
@asis #et TSF; /Triple Seta Falence ;olari.ed )ith
D
#tep 6: C4#M4 'ile eneration
5e&el o% Theory ;9FQ6 /Density +unctional Theory
@asis #et TSF; /Triple Seta Falence ;olari.ed * D
#C+ Calculation is done )ith SCRF=COSORS =ey)ord in
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"odified ashford ice algorithm
for C7#"7-# model'
Selectivity 5 ,apacity
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Selectivity 5 ,apacity
The selecti&ity is defined as the ratio of the composition of/nitrogen*sulphur compounds species in I$ rich phase /e,tract
and its composition in model diesel rich /raffinate phase'
"u=hopadhyay1UUV
The in&erse of the acti&ity coefficient of the species
/nitrogen*sulphur compoundsat infinite dilution in sol&ent rich
/e,tract phase' "u=hopadhyay : ao1UQV
86
2 1 2
1 2 1
/' !hase 0iesel !hase /' !hase
ij1max ij* 2* γ γ γ
γ γ γ
∞ ∞ ∞∞
∞ ∞ ∞
= ≈ ÷ ÷ ÷
12
1
1C
γ ∞
∞
= ÷
Separation of aromatic nitroen
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Separation of aromatic nitroen5 s+lph+r compo+nds
0ernary Diaram
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0ernary Diaram
TE"I"VTEt#7V0 10 20 >0 0 50 60 0 Q0 U0 100
9en.othiophene
0
10
20
>0
0
50
60
0
Q0
U0
100
8e,ane
0
10
20
>0
0
50
60
0
Q0
U0
100
E,perimental
C7#"7-# ;redictions
RMSD for Quaternary systems
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yy#'No Name of the systems NT$ model JNIPJ!C
modelC7#"7-#model
1 !M$MI4AcIBThiophene
;yridine?entane
0'> 1'6U '62
2 E"I"VEt#7VThiophene
;yridine?entane
0'12 0'1U 5'>
> !M$MIMe#43IBThiophene
;yridine?entane
1'U 1'60 6'
!M$MI4AcIBThiophene
;yridineCyclohe"ane
1'0> 1'6U 'Q5
5 !M$MI!t#47IBThiophene
;yridineCyclohe"ane
1'25 1'U0 5'U>
6 !M$MIMe#43IBThiophene
;yridineCyclohe"ane
1'0U 2' 5'>5
!M$MI4AcIBThiophene
;yridineToluene
0'U2Q 1'5 Q'1
Q !M$MI!t#47IBThiophene
;yridineToluene
1'2> 1'5 Q'
U !M$MIMe#43IBThiophene
;yridineToluene
0U'> 2'> 6'5>
S+mmary
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S+mmary
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Ac$nowledements
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c o ede e ts
Dr'Tamal 9anerYeeIIT
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Than>s, and 4?!! see 8ou ne@t time0