Gas solubility and Volumetric Behaviour of Carbon dioxide+lubricant

Transcription

Gas Solubility and Volumetric Behaviour of
Carbon Dioxide + Lubricant Systems
Josefa Fernández
[email protected]
Thermophysical Properties Laboratory,
University of Santiago de Compostela, Spain
Dr. Olivia Fandiño
Ms. Teresa Regueira
Dr. Luis Lugo
Dr. Enriqueta Lopez
Dr. María J. P. Comuñas
Dr. Alfonso Pensado
Dr. Josefa García
Colloquium Prof. Richon Paris, September 3
3--4, 2009
Introduction
Density
Solubility
Conclusions
Index

Introduction

Density of lubricants and their CO2 mixtures



Solubility of CO2 in lubricants



Experimental technique
Results
Results
Conclusions
Introduction
Problem
CO2
Density
Solubility
Systems of refrigeration Products
Conclusions
Environmental problems
Ozone Depletion
Global warming
o6
Introduction
Problem
CO2
Density
Solubility
Conclusions
CO2 AS ALTERNATIVE REFRIGERANT

Natural refrigerant: low cost

Low GWP (Global Warming Potential )
GWP(HFC) ≈1000·GWP(CO2)

Null ODP (Ozone Depletion Potential )

No flammable

Slight or no toxic action

High thermal conductivity

Low critical temperature: 30.976 ºC

High working pressure (Critical pressure: 73.77 bar)
3--4, 2009
Diapositive 4
o6
La principal v entaja de la utliización del CO2 como refrigerante alternativ o es su bajo coste, puesto que como todos sabemos es un producto
natural que no necesita de síntesis.
Además, una molécula de dióxido de carbono contribuy e al calentamiento global unas 1000 v eces menos que una molécula de HFC (que son
los actuales refrigerantes en uso). Otra característica importante es que el CO2 tiene un potencial de destrucción de la capa de ozono nulo.
Otras v entajas son la no inflamabilidad y su muy baja toxidad.
A todo esto debes añadir que este fluido presenta una alta conductiv idad térmica.
Como contraindicaciones, señalar que posee un muy baja temperatura crítica, lo que ha obligado a rediseñar los ciclos de refrigeración,
dando lugar a los ciclos transcríticos. Por otro lado resaltar la necesidad de utilizar may ores medidas de seguridad en estos equipos que la
presión de trabajo para los equipos que trabajan con CO2 es mucho más elev ada que la de los aparatos que utilizan HFCs.
Finalmente decir que estas contraindicaciones y a han sido superadas porque y a se están probando máquinas que emplean el CO2 como
refrigerante.
Olivia, 4/22/2009
Introduction
Problem
CO2
Density
Solubility
Systems of refrigeration
Products
Conclusions
Basic diagram of a refrigeration circuit
“The choice of lubricant has a great
impact on energy efficiency, reliability,
)
lifetime and noise levels of various
refrigeration systems”
Introduction
Density
Solubility
Conclusions
Basic circuit for CO2
Heat transfer
coefficients 
Viscosity grades 
Antiwear additives
Performance 
High solubility of the refrigerant
Viscosity  wear 
Introduction
Density
Solubility
Conclusions
Basic circuit for CO2
Oil accumulation
Heat transfer coefficients 
Phase separation
Poor oil return
Compressor wear
Oil accumulation
Introduction
Problem
CO2
Density
Solubility
Conclusions
Problems
in refrigeration systems
Miscibility
Lubricant
with CO2
Mineral oils
Immiscible
High
PAOs
Immiscible
Ester
Miscible
Miscibility
Presence
of compressor
Alkylbenzenes
Immiscible
Presence of refrigerant dissolved in the lubricant
Partially
Miscible
1.1
Immiscibility
CO2 con 8% PEC9
1.0
No return of oil to the compressor
PEC9
-3
r/g·cm
PAG
oil in cooling system
0.9
CO2
Accumulation of oil within
the
circuit
0.8
T=303.15 K
Pensado et al. J. Sup. Fluids 2007
Barotropic effect (density inversion
of the phases)
0.7
10
20
30
40
p/MPa
50
60
Introduction
Density
Solubility
0.15
100
p=25 MPa
CO2 + 8% PEC5
Temperature [°C]
h/mPa·s
0.13
CO2 con 8% PEB8
0.10
Conclusions
p = 40 bar
75
p = 50 bar
p = 60 bar
50
25
0.08
0
CO2 puro
0
0,2
0,4
0,6
0,8
1
Oil Content
0.05
20
30
40
50
60
70
T/ºC
Pensado et al. J. Sup. Fluids 2007
80
90
Temperatura de saturación CO2-aceite
Vaporization
Temperature
Fauser
et al. VTMS6
Conference 2003
Fauser et al. VTMS6 Conference 2003
The thermophysical properties of the circulating fluid (refrigerant with
small quantíties of the lubricant) are different of the pure refrigerant:
tranfer coeficient, viscosity, vaporization temperature, enthalpy,….
Similarly, the real lubricant has different properties than the pure
lubricant.
Introduction
Problem
CO2
Name
PEC5
PEC7
PEB8
PEC9
Density
Solubility
Pure Substance
Pentaerythritol esters
Pentaerythritol tetrapentanoate
Pentaerythritol tetraheptanoate
Pentaerythritol 2-ethylhexanoate
Pentaerythritol tetranonanoate
Conclusions
Mw
g·mol-1
472.61
584.82
640.93
697.04
Indications POE. For medium an big refrigeration systems, for semi-hermetic compressors
Introduction
Problem
CO2
Density
Solubility
Name
Pure Substance
DiPEC5
DiPEC7
DiPEiC9
DiPentaerythritol esters
Dipentaerythritol hexapentanoate
Dipentaerythritol hexaheptanoate
Dipentaerythritol hexaisononanoate
Viscosities of DIPEs are around ten times bigger that those of PEs.
Pensado et al. Ind. End. Chem. Res 2006a 2006b
Conclusions
Mw
g·mol-1
758.98
927.29
1095.61
Introduction
Problem
CO2
Name
Density
Solubility
Substance
Conclusions
Mw
g·mol-1
Polyalkylene glycols
PAG1
Poly(propylene glycol) dimethyl ether
~ 1700
PAG2
Poly(propylene glycol) dimethyl ether
~ 1400
PAG3
Poly(propylene glycol) monomethyl ether
~ 1200
Small polymers or propylene oxide are used in refrigeration mainly in automotive air
conditioning and heat pumps.
p1
Introduction
Problem
CO2
Density
Solubility
Name of mixture
Components
Conclusions
Viscosity (mPa·s)
PEB8 + PEC5
PEB8 + PEC7
PEB8 and PEC5
PEB8 and PEC7
32
32
POE0
From PEC5 to PEC9
32
POE1
From PEC5 to PEC9
From DiPEC5 to DiPEC9
68
POE2
From PEC5 to PEC9
100
POE3
220
POE4
From TMPC16 to TMPC20
91
T
M
P
j
Diapositive 13
p1
Ver trabajo Teresa
pepa, 8/11/2009
Introduction
Density
Solubility
Conclusions
Index

Introduction







Results
Results
Conclusions
3--4, 2009
Introduction
Density
Solubility
Conclusions
Mechanical oscillator densimeter
DMA HPM
3--4, 2009
Introduction
Density
Solubility
Conclusions
Calibration
 (T , p)  A(T , p )  2 (T , p )  B(T , p)
O1
278.15 K < T < 373.15 K
Lagourette et al. (1992)
Vacuum and water
A (T ,
p )
B (T, 0)  B(T, 0.1 MPa )
T ≥ 373.15 K
Lagourette et al. modified by Comuñas et al. JCED (2008)
Vacuum, water and n-decane
3--4, 2009
Diapositive 16
O1
Poner 0 K me parecía un poco exagerado.
Quizás quedaría mejor poner T< 373.15 K
Olivia, 8/28/2009
Introduction
Density
Solubility
Conclusions
Uncertainty Calculation
T < 373.15 K : Vacuum and water
  AT  2  BT , p 
 w T ,0.1 MPa 
A T   2
2
 w T ,0 .1 MPa    vacuum
T 
Applying the uncertainty propagation law:
 AT  

 AT  
 AT  
2
2
2
 u  w   
 u  w   
 u  0  
U  AT   2
  w 

  w 
  0 
2
2
2
1
2
 AT  

  2 A T  w 
 2 A T  0 
2
2
2
U  AT   2 
 u   w   
 u  w   
 u  0  
w
w




  w 

2
2
2
2
2
1
2
Introduction
Density
Solubility
Conclusions
Uncertainty Calculation
B(T,p) can be written as:
B T , p   AT   w2 T , p    w T , p 
 w T ,0.1 MPa 
2
B T , p   2

(T , p )   w (T , p )
w
2
 w T , 0.1 MPa    0 T 
 B T , p  

 B T , p  
 B T , p  
2
2
2
 u  w   
 u  w   
 u  0  
U B T , p   2 
  w 

  w 
  0 
2
2
2
1
  A(T ) 

  2  A (T )  2
 2  A (T )  2
2
 u  w   
 u  0 
U B T , p   2 
 1 u   w   
w
w
  w






2
w
2
2
0 w
2
2
2
0 w
2
2
2
1
2
Introduction
Density
Solubility
Conclusions
Uncertainties: A(T)
 AT  
  2 A T  w 
2
U  AT   2 
 u  w   
 u  w 2
w


  w 
2
Units
EA_4/02 Guide
u(ref)
u(T)
u(p)
u()
U(A(T))
Reference
material
Calibration
Resolution
Repeatability
Calibration
Resolution
Repeatability
Repeatability
Resolution
2
2
kg/m3
K
MPa
s
kg/m3s2
Estimate

 2 A T  0 
2
 
 u  0  
w



Divisor
0.01
3
0.020
0.010
0.005
0.02
0.01
0.01
5 10-4
-3
1 10
2
23
1
2
23
1
1
23
k=2
2
2
u(x)
kg/m3
0.006
0.0025
0.014
0.0075
7 10-8
Expression of the Uncertainty of Measurement in Calibration, European Cooperation for
Accreditation, EA-4/02, 1999.
1
2
Introduction
Density
Solubility
Conclusions
Uncertainties: B(T,p)
2
2
2
2
2 2
  2 A(T )  2






2


A
(
T
)
2


A
(
T
)
2
2
2
w
0 w
0 w
 u  w   
 u  0 
U B T , p   2 
 1 u   w   
w
w
  w






Units
EA_4/02 Guide
Reference
u(ref)
material
Calibration
u(T)
Resolution
Repeatability
Calibration
u(p)
Resolution
Repeatability
Repeatability
u()
Resolution
U(B(T,p))
kg/m3
K
MPa
s
kg/m3
Estimate
Divisor
0.01
3
0.020
0.010
0.005
0.02
0.01
0.01
5 10-4
-3
1 10
2
23
1
2
23
1
1
23
k=2
1
2
u(x)
kg/m33
0.006
0.0025
0.014
0.0075
0.5
3--4, 2009
Introduction
Density
Solubility
Conclusions
Uncertainties: ρ
  AT   BT , p 
2
2
  

  


 
2
2
2
 u BT , p  
U    2
 u  AT     u    
  
 AT  
 BT , p  

2
2

U    2 
 u  AT   2A u  
2 2
2
2
2
 u B T , p 
2

1
1
2
2
Segovia et al. J. Chem. Thermodyn., 41, 632, 2009.
3--4, 2009
Introduction
Density
Solubility
Conclusions
U  
(k=2)

       

-3 (T<373.15 K, and p ≥0.1 MPa)
1
0.7 kg·m
2
2
2
2
2 2
2
52kg·m
 -3u A(T=(373.15
T  2and
A 398.15)
u  K,uand
BT
, p MPa)
p =0.1
3 kg·m-3 (T=(373.15 and 398.15) K, and p >0.1 MPa)
EA_4/02 Guide
Units
 

Estimate Divisor u(x)
kg/m3
u()
u(A(T))
u(B(T,p))
u()
U()
U()
Repetibility
Resolution
s
5 10-4
-3
1 10
1
23
7 10-8
kg/m3s2
kg/m3
0.5
kg/m3
kg/m3
kg/m3/kg/m3
2
2
k=1
k=2
k=2
0.0075
0.25
0.25
0.35
0.7
8 10-4
Segovia et al. J. Chem. Thermodyn., 41, 632, 2009.
3--4, 2009
Introduction
Density
Solubility
Conclusions
DMA HPM: experimental deviations
Toluene: 283.15-398.15 K up to 70 MPa
() Cibulka and Takagi. J.
Chem. Eng. Data, 1999,
44, 411-429.
() Assael et al. Int. J.
Thermophys., 2001, 22,
789-799.
() Lemmon and Span. J.
Chem. Eng. Data, 2006,
51, 785-850.
Bias (%)
AAD (%)
Dmax (%)
Cibulka and Takagi
0.002
0.03
0.09
Assael et al.
0.04
0.05
0.13
Lemmon and Span
0.02
0.03
0.08
Introduction
Density
Solubility
Conclusions
n-Decane: 283.15-398.15 K up to 130 MPa
AAD %
0.02
0.06
(●) Troncoso et al. J. Chem. Eng. Data, 2004, 49, 923-927.
0.03
() Zúñiga-Moreno et al. J. Chem. Eng. Data, 2005, 50, 1030-1037. 0.03
( ) Cibulka and Takagi. J. Chem. Eng. Data, 1999, 44, 411-429.
() Lemmon and Span. J. Chem. Eng. Data, 2006, 51, 785-850.
Introduction
Density
Solubility
Conclusions
Correction due to the viscosity for HPM densimeter
 HPM  
 7 . 5  10  4
 HPM
 HPM  
 0 . 4482
 HPM
Fandiño et al. J: Chem. Thermodyn. 2009, ASAP
  0 . 1627   10  4
Introduction
Density
Solubility
Conclusions
Correction due to the viscosity for several densimeters
DMA HPM
DMA HPM
DMA 602H
DMA 602H
DMA 512P
DMA 512P
DMA 512P
DMA HPM
• η<289 mPa·s
• η<100 mPa·s

 512P   real
  0 .5  0.45 
 512 P
 10
4
 H PM  
 0 .4482
 HPM
• η>400 mPa·s
 51 2P   rea l
 5 10 4
5 12P
 HPM  
 7 .5  10  4
 HPM
  0.1627  10  4
• η>289 mPa·s
Introduction
Density
Solubility
Conclusions
Squalane: 298.15-398.15 K up to 60 MPa
with correction term due to the viscosity
(□) Fandiño et al. J. Chem. Eng.
Data, 2005, 50, 939-946
() Kuss y Taslimi. Chem. Ing.
Tech., 1970, 42, 1073-1081
(♦) Fermeglia y Torriano. J.
Chem. Eng. Data, 1999, 44,
965-969
Kuss and Taslimi
() Kumagai et al. Int. J.
Bias (%)
AAD (%)
Thermophys.,
2006,Dmax
27, (%)
376-393
0.02
0.03
0.05
Fandiño et al.
-0.02
0.02
0.03
Kumagai et al.
0.08
0.09
0.19
Fermeglia and Torriano
0.005
0.005
0.005
Introduction
Density
Results
Solubility
Conclusions
Fandiño et al. J. Chem. Eng. Data 2005, Green Chemistry 2006, Ind. Eng. Chem. Res. 2006
Introduction
Density
Results
Fandiño et al. J. Chem. Thermodyn. ASAP 2009
Solubility
Conclusions
Introduction
Density
Solubility
Conclusions
Summary Density for all Fluids
For esters
 -COO-   r
 -CH2-   r
Branched
r
For endcapped PAGs
 -PO-   r
r(alkanes)<< r(POE4) < r(PEs) < r(DiDP) < r(PAG) < r(DiPEs)
Introduction
Density
Results
Solubility
Conclusions
Isothermal Compressibility
 -COO-   k T
323,15 K
For PEs, DiPEs
 -CH2-   k T
Branched
  kT
For endcapped PAGs
 -PO-   k T
k T(POE4) < k T(DiDP)
DiDP) < k T(DiPE
DiPE)) < k T(PE
PE) < k T(PAG
PAG) << k T(alkanes)
Introduction
Density
Results
Solubility
Conclusions
Isobaric Thermal Expansivity
 -COO-   a p??
PAG1
For PEs, DiPEs,alkanes
323,15 K
The crossing point of the
Crossing point
isothermal
of
a
 -CH2- p has
 a been
found for the most ofp the
fluids
except for
Branched
 the
 aDiPEs.
p
For PAGs (dialkylated)
 -PO-   a p
a p(DiPE)< a p(POE4) < a p(DiDP) < a p(PAG) << a p(alkanes)
Introduction
Density
Solubility
Conclusions
High Pressure
Densimetry
B)
Lubricant + Refrigerant Mixtures
Introduction
Density
Solubility
Conclusions
The sample is a mixture of two components:


lubricant: liquid at atmospheric pressure
refrigerant: gas at atmospheric pressure
Transfer the sample must be carried out
through enclosed recipient
Introduction
Density
Solubility
Measurements: DMA HPM
Conclusions
The new transfer
system
Introduction
Density
Solubility
Conclusions
Transfer system
Syringe pumps
Teledyne ISCO
Thermostatic baths
Grove regulator
Pressure
limiting valve
Introduction
Density
Solubility
Conclusions
Transfer system
Syringe pumps
Teledyne ISCO
Thermostatic baths
Grove regulator
Pressure
limiting valve
Moles of the fluid i in time unit
 i (T , p)·i
ni 
Mi
Introduction
Density
Solubility
Conclusions
Uncertainties: mole fraction
Units
Estimation
Divisor
u(T)
K
0.5
u(p)
MPa
u(x)
xCO2≤0.8
xCO2≥0.8
√3
0.0003
0.0004
0.05
√3
8·10-5
4·10-5
u(rCO2)
0.05% r
2
0.0001
2·10-5
u(fCO2)
0.5% f
2
0.001
0.0004
0.7
2
0.0001
2·10-5
0.5% f
2
0.001
0.0004
0.002
0.001
0.004
0.002
u(ri)
u(fi)
kg·m-3
u(xCO2)
U(xCO2)
(k=2)
EA_4/02 Guide
Introduction
Density
Results
Solubility
Conclusions
x Carbon dioxide + (1-x) n-decane
Introduction
Density
Results
Solubility
Conclusions
Crossing point of lines of
constant concentration
Uncertainty
AAD (%)
Zúñiga-Moreno et al. (2005)
0.2 kg·m-3
0.1
Bessières et al. (2001)
0.2 kg·m-3
0.1
Cullick and Mathis (1984)
0.5 kg·m-3
0.2
Introduction
Density
Results
Solubility
Conclusions




1
1
1
1




v (T , p, x )  x M CO 2

 (1  x ) M oil 

  (T , p)  CO (T , p) 
  (T , p) oil (T , p) 

2

E
For T>314 K is not correct to name excess
properties since the CO2 is a supercritical fluid
(, , , ) Zúñiga-Moreno et al. J. Chem. Eng. Data, 2005, 50, 1030-1037.
() Bessières et al. J. Chem. Eng. Data, 2001, 46, 1136-1139
Introduction
Density
Results
Solubility
Conclusions
x CO2 + (1-x) DiPEC5
p
0.1 MPa – 120 MPa
T
278.15 K – 398.15 K
x= 0
x= 0.209
x= 0.597
1.12
278.15 K
r , g·cm
-3
1.07
1.02
398.15 K
0.97
x= 0.209
0.92
0
20
40
60
80
100
120
p, MPa
3--4, 2009
Introduction
Density
Results
Solubility
Conclusions
333.15 K
x= 0.597
1 .2
1.14
1 .0
1.10
() x= 0
-3
0 .8
() x= 0.209
r , g·c m
r , g·c m
-3
120 MPa
0 .6
1.06
1.02
() x= 0.597
0 .4
() x= 1
CO2
0.98
0 .2
10 MPa
0.94
0
20
40
60
80
p, MPa
100
120
27 3.15
303.15
333.15
T, K
363.1 5
39 3.15
3--4, 2009
Introduction
Density
Results
Solubility
Conclusions
Introduction
Density
Results
Solubility
Conclusions
 0.000
 0.301
 0,701
 0.984
 1.000
Same behaviour
for other
asymmetric
mixtures. as found
by Marchi et al.,
Comuñas et al.
and Pensado et al.
Crossing point of lines of
constant concentration
Introduction
Density
Results
Solubility
Conclusions
CO2 + PEs
0.20
1.05
0.18
0.16
/ mPa·s
/ g·cm
-3
1.00
0.95
0.90
0.14
0.12
0.85
0.10
0.80
0.08
0.75
0.06
10
20
30
40
50
60
10
20
p / MPa
(■) xPEB8=0.0058
() xPEB8=0.0115
30
40
50
60
p / MPa
at 303.15 K and 10 MPa
hPEB8 ~ 83 mPa·s
Pensado et al. J. Sup. Fluids 2007, AIChE 2008
3--4, 2009
Introduction
Density
Results
Solubility
Conclusions
CO2 + PEs
Isothermal Compressibility
x PEB8 + (1-x) CO2
k T CO2 ~ 13·10-3 MPa-1
k T PEB8 ~ 6·10-4 MPa-1
at 303.15 K and 15 MPa
12
10
xPEB8 = 0.0058
xPEB8 = 0.0155
/ MPa
-1
353.15 K
T
/ MPa
8
T
3
6
353.15 K
6
10
10
3
8
-1
10
4
4
303.15 K
2
10
20
303.15 K
2
30
40
50
60
10
20
30
40
50
60
p / MPa
p / MPa
Pensado et al. J. Sup. Fluids 2007, AIChE 2008
3--4, 2009
Introduction
Density
Solubility
Conclusions
Index

Introduction







Results
Results
Conclusions
3--4, 2009
Introduction
Density
Solubility
Conclusions
Isochoric technique
For non-volatile liquids
Ranges:
o Pressure 0.1 a 10 MPa
oTemperature 283-348 K
Whalström and Vamling J. Chem. Eng. Data 1999 44, 823–828.
Fandiño et al. J. Chem. Eng. Data 2008, 53, 1854–1861
Introduction
VC
Density
Solubility
Conclusions
Vacuum
pump
PC
Environmental Chamber
V1
±0.003 MPa
V3
V2
Pressure
Transduce
Transducer
V5
V4
Temperature
±0.02 K
Lubricant
CO2
Magnetic Stirrer
Measurement
cell
Auxiliary
Thermostatic Bath
Gascylinder
OFF
ON
283.15 ≤ T/K ≤ 348.15
p/MPa ≤ 8.0
Introduction
Density
Solubility
Conclusions
VC
Pressure const.
PC
Equilibrium
Environmental Chamber
Temperature const.
V1
V3
V2
Pressure
Transduce
Transducer
V5
• Measured p, T for
the
V4
CO2
Number of moles of
Equation of state
• Known Vsystem
CO2
Temperature
CO2 gas in the system
Moles of CO2 absorbed in the lubricant =
Magnetic Stirrer
= initial moles CO2
-
moles CO2 gas equilibrium
Auxiliary
Thermostatic Bath
OFF
ON
Introduction
Density
Solubility
Conclusions
Calculations
Vsist. ga s (Tini c )
Vsist. gas (Teq . sist. gas ) Vcélula (Teq. l iq )  Vliq (Teq . liq )
 v

v
v
v CO2 (Tinic , pini c ) vCO2 (Teq . si st. gas , p )
v CO
(Teq . li q , p )
2
ng 
vCO2 . abs (Teq . liq )
1 v
vCO2 (Teq. l iq , p )
m g  M gas n g
Vsis . gas (T )
Volume of system gas
Vcell ( T )
Volume of measurement cell
Vliq (T , p )
Volume of lubricant inside of measurement cell
v
v CO
(T , p)
2
Mole volume of CO2 in vapour phase
v CO2 .abs (T ) Mole volume of CO2 absorbed
Introduction
Density
Solubility
Conclusions
Uncertainties: mole fraction
Estimation
Units
u(x)
Low xCO2
High xCO2
u(T)
0.02
K
0.0003
u(p)
0.0007
MPa
u(rl)
0.0002
g·cm-3
2·10-5
u(vvg)
0.04%
g·cm-3
0.0009
u(ml)
0.004
g
2·10-5
u(Vsist. gas)
0.1
cm-3
0.001
0.0001
u(Vmeas. cell)
0.2
cm-3
0.002
0.0001
u(Vgas abs)
50%
cm-3
0.0004
0.007
u(xCO2)
k=1
0.003
0.007
U(xCO2)
k=2
0.006
0.01
U(xCO2) %
k=2
6
2
0.001
0.0001
Introduction
Density
Solubility
Results
Conclusions
Vapor Pressures
-10
Símbolos: puntos experimentales
(Razzouk et al. 2007)
PEC5
PC-SAFT
-12
lnP(bar)
-14
-16
PEC7
PEC9
-18
-20
-22
0.0020
PEB8
0.0022
0.0024
0.0026
0.0028
0.0030
0.0032
1/T(K)
Razzouk et al. / Fluid Phase Equilibria 260 (2007) 248–261
3--4, 2009
Introduction
Density
Solubility
Results
Conclusions
x CO2 + (1-x) PE
xCO2(PEC5) <xCO2(PEC7) <xCO2(PEB8) <xCO2(PEC9)
Introduction
Density
Solubility
Results
Conclusions
Comparison with literature
AAD with
Bobbo et al.
2%
IIR Conferences in Vicenza
(2005)
xCO2(PECn) ≈xCO2(PEBn)
Introduction
Density
Solubility
Results
Conclusions
Comparison with literature
 PEC4. Bobbo et al. (2005)
 PEC5
 PEBM5. Bobbo et al. (2007)
 PEC6. Bobbo et al.
 PEBM6. Bobbo et al. (2007)
 PEC7
 PEBM7. Bobbo et al. (2007)
 PEB8
 Castrol Icem atic SW32. Bobbo et al. (2006)
n   wCO2(PECn)
wCO2(PECn) < wCO2(PEBn)
Introduction
Density
Solubility
Conclusions
Results
wCO2(POE3) <wCO2 (DiPEC7)< wCO2(PAG2)
Introduction
 PEC7
 PEB8
 DiPEC7
 PAG2
 POE ISO56. Marcelino-Neto (2006)
 PAG. García et al. (2008)
 Squalane. Kukova (2003)
POE3
Density
Solubility
Results
Conclusions
A2
Introduction
Density
Solubility
Results
pi  x i psat
Conclusions
Ley de Raoult
CO2+PEs
Negative deviations show the presence of stronger
interactions between unlike molecules in the mixture
3--4, 2009
Diapositive 60
A2
La solubilidad aumenta ligeramente con la masa molecular de los aceites estudiados. El efecto es inv erso pero mas claro si se observ a en
porcentaje en peso. Esto también ha sido encontrado por Bobbo y co. como v eremos a continuación.
La solubilidad es may or que la ideal. Desv iación negativ a de la ley de Raoult. (Ver que implicaciones tiene).
avi, 9/7/2006
Introduction
Density
Solubility
Results
Conclusions
(b)
Fin ELLV
18
305
(a)
CO2 + PAG2
12
T/K
313.15 K
Presión/ MPa
14
373.15 K
16
280
miscible
inmiscible
255
10
8
230
298.15 K
0
6
4
2
00
20
40
60
masa de CO2 % en PAG2
278.15 K
EL LV
0.2
0.4
0.6
0.8
fracción en peso de CO2 en PAG2
1
experimental (Hauk 2001)
PC-SAFT kij(T),
Garcia et al. J Sup. Fluids 2007,2008
80
100
Introduction
Density
Solubility
Conclusions
Conclusions
Introduction
Density
Solubility
Conclusions
We have implemented a computer-operated-densimetric
equipment and evaluated of the density uncertainty using
the EA-4/02 Guide:
.
With (k=2),
0.7 kg·m-3 (T<373.15 K, and p≥0.1 MPa)
5 kg·m-3 (T=(373.15 and 398.15) K, and p=0.1 MPa)
3 kg·m-3 (T=(373.15 and 398.15) K, and p>0.1 MPa)
We have presented a new loading system for gas + liquid
compressed systems, which consists in two syringe pumps
ISCO Teledyne with electronic valves which deliver the gas
and the liquid pure components at programmable constant
flow rates.
New pVTx values were obtained for
DiPEC7, DiPEC5) are presented.
binary CO2 + (decane,
Introduction
Density
Solubility
Conclusions
The uncertainties of the solubility measurements
obtained, following the guide EA-4/02,
are smaller than
6% to low xCO2 and 2% to high xCO2
The solubility increases with the pressure and decreases
with the temperature to all mixtures.
xPEs < xDiPEC7 < xPAG2
The solubilities, expressed in terms of mole fractions, do
not change practically with the branching and the size of
the acid chains
Negative deviations of Raoult’s law  Strong interactions
between different fluids due to important quadrupole
momentum of the CO2
ACKNOWLEDGEMENTS
Dr. Steve J. Randles, UNIQEMA (now Croda)
• Prof. Agilio Padua, University Blaise Pascal
• Prof. Jacques Jose, Dra Mokbel and Razzouk, Un. Lyon 1
• Dr. M. Youbi-Iddrissi, Cemagref, Paris
• Prof. José Juan Segovia, University of Valladolid
• Ministerio Educación y Ciencia
• Xunta de Galicia
Happy Birthday, Dominique
Introduction
Density
Solubility
Thanks
For your attention
Conclusions
Introduction
Solubility
Conclusions
Results
Gas absorbed volume
1- Estimations
 Zellner et al. Ind. Eng. Chem. Fundam., 1970, 9, 549-564
 Brelvi and O’Connell.
AlChE J., 1972, 18, 1239-1243
 Heidemann y Prausnitz. Ind. Eng. Chem. Process Des.
Dev., 1977, 16, 375-381
pc1V1
Tpc1
 0.095  2,35
RTc1
c2Tc1
3--4, 2009

Gas solubility and Volumetric Behaviour of Carbon dioxide+lubricant

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