Norwegian University of Science and Technology (NTNU) 1 Outline - - PowerPoint PPT Presentation

SLIDE 1

1

Norwegian University of Science and Technology (NTNU)

Thermodynamic consistency in modeling

• f SLE and VLE

in aqueous alkanolamine solutions

Ardi Hartono and Hallvard F Svendsen PCCC2 Conference Bergen, September 17-20, 2013

SLIDE 2

2

 Introduction  Theory

• VLE (Vapor-Liquid Equilibrium)
• SLE (Solid-Liquid Equilibrium)

 Modeling : NRTL Framework as an example  Results

• MEA+H2O
• DEEA+H2O
• AMP+H2O

 Conclusions

Outline

SLIDE 3

3

 Rigorous thermodynamic models based on excess Gibbs energy (eNRTL and eUNIQUAC) are capable of representing both Solid-Liquid-Equilibria (SLE) and Vapor-Liquid-Equilibria (VLE) in aqueous alkanolamine solutions

Introduction

 A robust and accurate modeling relies on the quality and type of data used to regress the parameters to get the best representation of the data.  Different apparatuses provide different equilibrium data:

• Ebulliometer experiments usually generate PTxy data which can be used to

determine the activity coefficient for both amine and water.

• A calorimetric measurement can provide excess enthalpy of mixing and

reaction as well heat capacity

• Freezing point depression measurements provide SLE and water activity data .

 When comparing activity coefficients of water from VLE and SLE data often inconsistencies are seen: e.g.

• the excess enthalpies calculated were slightly skewed toward higher amine

concentrations when a best fit to freezing point depressions was achieved .

• the minimum value of the excess enthalpy was fitted optimally but the

freezing point depression was found to be under-predicted, in particular at higher concentrations.

SLIDE 4

4

 Examples: MEA +H2O

Schmidt, et al., 2007

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1

x1 (-) γi (-)

γMEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10 10

1

10

2

x1,y1 (-) P (kPa)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Touhara, et al., 1982) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2

• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011 Cheng, et al., 1992

Posey, 1996

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1

x1 (-) γi (-)

γMEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Touhara, et al., 1982) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2

• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011 Cheng, et al., 1992 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10 10

1

10

2

x1,y1 (-) P (kPa)

VLE (P-T-x and P-T-x-y) and Excess Enthalpy. VLE (P-T-x and P-T-x-y), Excess Enthalpy and Freezing Point. Overpredict Fits Overpredict Underpredict Skewed

SLIDE 5

5

 Examples:

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Touhara, et al., 1982) 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1

x1 (-) γi (-)

γMEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10 10

1

10

2

x1,y1 (-) P (kPa)

0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2

• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011 Cheng, et al., 1992

Zhang, et al., 2011 Hessen, et al., 2010

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1

x1 (-) γi (-)

γMEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10 10

1

10

2

x1,y1 (-) P (kPa)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Touhara, et al., 1982) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2

• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011 Cheng, et al., 1992

To find the origin of the discrepancy between measured data used for the thermodynamic modeling of the activity coefficient of water.

 AIM: VLE (P-T-x and P-T-x-y), Excess Enthalpy and Heat Capacity. VLE (P-T-x and P-T-x-y), Excess Enthalpy and Freezing Point. Overpredict Fits Underpredict Overpredict

SLIDE 6

6

Theory VLE SLE

, ,

( ) ln

E i i T P ni

nG RT n g é ù ¶ ê ú = ê ú ¶ ë û

2 ,

( )

E E P x

H G RT RT T é ù ¶ ê ú

• = ê

ú ¶ ë û

, E E P P x

H C T é ù ¶ ê ú = ê ú ¶ ë û ( , ) ( , ) ( , ) ( , ) ln ( , ) ( , ) ln ln ln

s i s s i s i i s i

T p T p T p T p RT f T p T p RT f f G R T RT a f

      

m m m m m m = = + = + D = × × = - ( , ) ( , ) ( , ) ( , ) ln ( , ) ( , ) ln

v i v v i v v i i i i i i i

T p T p T p T p RT f T p T p RT f f f x P P y

       

m m m m m m g = = + = + = × × = × × F

( ) exp 1

i i ì i i

V P P RT

 

 f f ° ì ü ï ï

• ï

ï F º ×

• »

í ý ï ï ï ï î þ

ln

i i

RT x G g

• = D

1 1 ln

T T f f P i i P T T f f

H S C x C dT dT RT R RT R T

 

g D D D

• =
• +

D

• ò

ò

` f f f

H T S

 

D = D

( )

1 1 ln 1

T T f P i i R P f T T f f

H C x T C dT dT RT RT R T



g D D

• =
• +

D

• ò

ò

T f P Tf T P f Tf s P P P

G H T S H H C dT C S S dT T C C C

  

D = D

• D

D = D + D D D = D + D =

• ò

ò

Prausnitz, et al., 1999, Molecular Thermodynamics of Fluid-Phase Equilibria Hojjati and Rohani, 2006, Measurement and prediction solubility of Paracetamol in Water-Isopopanol solution

SLIDE 7

7 1 1

T T P P T T f f

C C dT dT RT R T D D º

ò ò

Case 1

( )

ln 1

f i i R f

H x T RT



g D =

• f

R

T T T =

( )

1 1 ln 1

T T f P i i R P f T T f f

H C x T C dT dT RT RT R T



g D D

• =
• +

D

• ò

ò

Case 2

ln ln

f i i R f

H x T RT



g D

• =

P f

C S  D @D

Case 3

P Tf

C k D @

( ) ( )

ln 1 1 ln

f P i i R R R f

H C x T T T RT RT



g D D

• =
• +

+

•  Posey (1996), Cheng et al. (1993) and Hessen, et al. (2010)

SLIDE 8

8

Case 4

P

C a bT D = +

( ) ( )

1 ln 1 1 ln 2 2

f f i i R R R R R f

H bT a x T T T T T RT R R



g D æ ö ÷ ç

• =
• +

+

• +
• ÷

ç ÷ è ø

Case 5

( )

P

c C a bT T TQ D = + +

• (

) ( )

( )

( )

2

1 ln 1 1 ln ln ln 2

f f i i R R R f R f f

H bT T T T a x T T T T T c T RT R RT T T T



g

Q Q

ì ü ï ï D

• ï

ï

• =
• +

+

• +
• +
• í

ý ï ï

• ï

ï î þ

( )

1 1 ln 1

T T f P i i R P f T T f f

H C x T C dT dT RT RT R T



g D D

• =
• +

D

• ò

ò

 Ge and Wang (2009) and Hartono, et al. (2013)  Fosbøl, et al. (2009 and 2011)

SLIDE 9

9

Thermo physical property of water as solvent

6009.4

f

J H mol



D =

50 100 150 200 250 300 350 400 450 500 550 10 20 30 40 50 60 70 80 90 100

Heat Capacity, Cp (J⋅mol-1⋅K-1) T (K)

∆Cp=Cpl-Cps ∆Cp= a + b.*T Cps Cpl

∆Cp

Tf=273.15K

37.97

P

J C K mol D = × 75.929 0.1405

P

J C T K mol D =

• ×

×

( )

4

2.45634 10 75.929 0.1405 200

P

J C T T K mol

• ×

D =

• × -
• ×

DIPPR-Design Institute for Physical Properties (2004)

SLIDE 10

10

2 2 2 2 Sol Sol Sol Sol i i 1 1 1 1 i Sol Sol

( ) ( ) ( ) ( ) ( ) ( )

Exp calc E Exp E calc F Exp F calc Exp calc n n n n Sol Sol Exp Exp E Exp F Exp i i i i Sol

P P H H OF P H g g g

= = = =

æ ö æ ö æ ö æ ö

• Q
• Q
• ÷

÷ ÷ ÷ ç ç ç ç ÷ ÷ ÷ ÷ = + + + ç ç ç ç ÷ ÷ ÷ ÷ ç ç ç ç ÷ ÷ ÷ ÷ ç ç ç ç Q è ø è ø è ø è ø

å å å å

model exp 1 exp

1

n i

AARD n

=

Â

• Â

= Â

å

Hertzberg, T and Mejdell, T., 1998, MODFIT for Matlab: Parameter Estimation in a General Nonlinear Multiresponse Model.

Modeling

Species Melting/ Freezing Point (°C)

Water MEA 10.3 AMP 67 DEEA

• 70

SLIDE 11

11

Results

 MEA+H2O

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1

x1 (-) γi (-)

γMEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10 10

1

10

2

x1,y1 (-) P (kPa)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Touhara, et al., 1982) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16

• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011 Cheng, et al., 1992 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1

x1 (-) γi (-)

γMEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10 10

1

10

2

x1,y1 (-) P (kPa)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Touhara, et al., 1982) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16

• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011 Cheng, et al., 1992 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1

x1 (-) γi (-)

γMEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10 10

1

10

2

x1,y1 (-) P (kPa)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Touhara, et al., 1982) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16

• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011 Cheng, et al., 1992

 Case 1  Case 2  Case 3

SLIDE 12

12

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1

x1 (-) γi (-)

γMEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10 10

1

10

2

x1,y1 (-) P (kPa)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Touhara, et al., 1982) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16

• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011 Cheng, et al., 1992 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1

x1 (-) γi (-)

γMEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10 10

1

10

2

x1,y1 (-) P (kPa)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Touhara, et al., 1982) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16

• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011 Cheng, et al., 1992

 Case 4  Case 5

 MEA+H2O

SLIDE 13

13

0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16

• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011 Cheng, et al., 1992

 MEA+H2O

SLIDE 14

14

 AMP+H2O

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6

x1 (-) γi (-)

γAMP γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 80 90 100 110 120 130 140 150 160 170

x1,y1 (-) t (°C)

xAMP @ 66.7 kPa yAMP @ 66.7 kPa xAMP @ 80.0 kPa yAMP @ 80.0 kPa xAMP @ 101.3 kPa yAMP @ 101.3 kPa 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

35°C (Mathonat, et al., 1997) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16

• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6

x1 (-) γi (-)

γAMP γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 80 90 100 110 120 130 140 150 160 170

x1,y1 (-) t (°C)

xAMP @ 66.7 kPa yAMP @ 66.7 kPa xAMP @ 80.0 kPa yAMP @ 80.0 kPa xAMP @ 101.3 kPa yAMP @ 101.3 kPa 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

35°C (Mathonat, et al., 1997) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16

• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6

x1 (-) γi (-)

γAMP γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 80 90 100 110 120 130 140 150 160 170

x1,y1 (-) t (°C)

xAMP @ 66.7 kPa yAMP @ 66.7 kPa xAMP @ 80.0 kPa yAMP @ 80.0 kPa xAMP @ 101.3 kPa yAMP @ 101.3 kPa 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

35°C (Mathonat, et al., 1997) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16

• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011

 Case 1  Case 2  Case 3

SLIDE 15

15

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6

x1 (-) γi (-)

γAMP γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 80 90 100 110 120 130 140 150 160 170

x1,y1 (-) t (°C)

xAMP @ 66.7 kPa yAMP @ 66.7 kPa xAMP @ 80.0 kPa yAMP @ 80.0 kPa xAMP @ 101.3 kPa yAMP @ 101.3 kPa 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

35°C (Mathonat, et al., 1997) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16

• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6

x1 (-) γi (-)

γAMP γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 80 90 100 110 120 130 140 150 160 170

x1,y1 (-) t (°C)

xAMP @ 66.7 kPa yAMP @ 66.7 kPa xAMP @ 80.0 kPa yAMP @ 80.0 kPa xAMP @ 101.3 kPa yAMP @ 101.3 kPa 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

35°C (Mathonat, et al., 1997) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16

• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011

 Case 5  Case 4

 AMP+H2O

SLIDE 16

16

0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2

• 35
• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011

 AMP+H2O

SLIDE 17

17

 DEEA+H2O

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10

• 1

10 10

1

10

2

γDEEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10

1

10

2

x1,y1 (-) P (kPa)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 3
• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Mathonat, et al., 1997) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2

• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Arshad, et al., 2013 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10

• 1

10 10

1

10

2

γDEEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10

1

10

2

x1,y1 (-) P (kPa)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 3
• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Mathonat, et al., 1997) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2

• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Arshad, et al., 2013 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10

• 1

10 10

1

10

2

γDEEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10

1

10

2

x1,y1 (-) P (kPa)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 3
• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Mathonat, et al., 1997) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2

• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Arshad, et al., 2013

 Case 1  Case 2  Case 3

SLIDE 18

18

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10

• 1

10 10

1

10

2

γDEEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10

1

10

2

x1,y1 (-) P (kPa)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 3
• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Mathonat, et al., 1997) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2

• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Arshad, et al., 2013 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10

• 1

10 10

1

10

2

γDEEA γH2O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 10

1

10

2

x1,y1 (-) P (kPa)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

• 3
• 2.5
• 2
• 1.5
• 1
• 0.5

x1 (-) HE (kJ/mol)

25°C (Mathonat, et al., 1997) 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2

• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Arshad, et al., 2013

 Case 4  Case 5

 DEEA+H2O

SLIDE 19

19

0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2

• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Arshad, et al., 2013

 DEEA+H2O

SLIDE 20

20

Conclusions

 5 different cases to estimate the freezing point depression were tested for aqueous MEA, DEEA and AMP solutions.  Physical/ thermo physical properties of Water/Ice were only used.  When the freezing point differences between solute (alkanolamine) and solvent (water) is larger, none of the suggested cases were able to predict the data.  A systematic error in the measurements ??  Challenge to the selected thermodynamic model??  The required thermal and physical properties should be from the alkanolamines solution??

SLIDE 21

21

0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16

• 35
• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Fosbøl, et al., 2011

FutureWork

 AMP + H2O

0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2

• 35
• 30
• 25
• 20
• 15
• 10
• 5

x1 (-) Θ1 (°C)

Arshad, et al., 2013

 DEEA + H2O

SLIDE 22

22 Norwegian University of Science and Technology

We greatly appreciate for the financial support:

• The CCERT project supported by:

 The Research Council of Norway (NFR 182607)  Shell Technology Norway AS  Metso Automation  Det Norske Veritas AS  Statoil AS

Thank you!