improvement of lipophilic-amine-based thermomorphic .... technical chemistry b prof. dr. david w....

Lab. Technical Chemistry BProf. Dr. David W. Agar

Improvement of lipophilic-amine-based thermomorphic

biphasic solvent for energy-efficient carbon capture

Jiafei Zhang, David W. Agar

Trondheim

15.06.2011

Shell’s research project:Development of novel amineabsorbents for CO2 capture

TCCS-6, Session A2 Topic: Post-combustion Solvents

Improvement of lipophilic-amine-based thermomorphic biphasic solvent for energy-efficient carbon capture Jiafei Zhang

Lab. Technical Chemistry BProf. Dr. David W. Agar 11

Outline

Motivation

Concepts

Solvent performance

Challenges and amelioration

Summary

1



Outline

Motivation

Concepts

Solvent performance


Summary

Global warmingShortcomings of conventional solventsAdvantages of novel biphasic solvents

2



Motivation

Technical shortcomings of conventional solvents:

e.g. monoethanolamine (MEA)High energy consumptionHigh quality of heat: 130-150 °CSignificant amine loss by degradation

Major superiorities of novel biphasic solvents:

Regeneration temperature 80°CUse of waste heat for desorptionGood chemical stabilityHigh net CO2 loading capacity

Challenges? New generation absorbents

Anodic

Fe Fe2+ + 2e-

Catodic

2H+ + 2e- 2H0

Wet CO2 corrosion

CO2 + H2O HCO3- + H+

Wet CO2 corrosion


Amine corrosion

Fe + 2RNH3+ Fe2+ + 2H0 + 2RNH2

Anodic

Fe Fe2+ + 2e-

Catodic

2H+ + 2e- 2H0

Anodic

Fe Fe2+ + 2e-

Anodic

Fe Fe2+ + 2e-

Catodic

2H+ + 2e- 2H0

Catodic

2H+ + 2e- 2H0

Wet CO2 corrosion


Wet CO2 corrosion


Wet CO2 corrosion


Wet CO2 corrosion


Wet CO2 corrosion


Amine corrosion

Fe + 2RNH3+ Fe2+ + 2H0 + 2RNH2

Amine corrosion

Fe + 2RNH3+ Fe2+ + 2H0 + 2RNH2

3



Outline

Motivation

Concepts

Solvent performance


Summary

Lipophilic aminePhase changeTBS absorbentOther CO2 capture process with LLPS

4

(a) Homogeneous absorption (b) Heterogeneous desorption

CO2

Heating

Aqueous phase

Organic phase

CO2

Cooling

R1R2R3N + CO2 + H2O R1R2R3NH+ + HCO3-R1R2R3N + CO2 + H2O R1R2R3NH+ + HCO3

-R1R2R3N + CO2 + H2O R1R2R3NH+ + HCO3-R1R2R3N + CO2 + H2O R1R2R3NH+ + HCO3

-


CO2CO2

Heating

Aqueous phase

Organic phase

Aqueous phase

Organic phase

CO2CO2

CoolingCooling




-

Liquid-liquid phase separation (LLPS)



Concepts I

Novel amines

Alkanolamine vs lipophilic amine

Examples of lipophilic amineHexylamine (I) HADipropylamine (II) DPAN,N-Dimethylcyclohexylamine (III) DMCA

N

R

(H)R R(H)N

R

(H)R R(H)

OH

N

NH

5

NH2

Hydrophobic Hydrophilic



Concepts II

Phase change

Thermomorphic phase transitionLow temperature single phaseHigh temperature dual phases

Lower critical solution temperature (LCST)

Expected

6

0,0 0,2 0,4 0,6 0,8 1,0-20

0

20

40

60

80 Hexylamine (I) A1 DPA (II) DMCA (III) Frozen

Tem

pera

ture

[°C

]

Mass fraction of lipophilic amine in aqueous solution [g/g]

Two phases

Single phase



Concepts III

Novel absorbent: thermomorphic biphasic solvent (TBS) Absorption: single phase Regeneration: two phases

Lean solvent cooling to 30-40°C: homogeneousRich solvent heating to 70-80°C: biphasic


CO2

Heating

Aqueous phase

Organic phase

CO2

Cooling



-


CO2CO2

Heating

Aqueous phase

Organic phase

Aqueous phase

Organic phase

CO2CO2

CoolingCooling




-

7

Process Flow Sheet



Concepts IV

‘Self-Concentration’ CO2Capture Process

Univ. of Kentucky

DMXTM process with demixing solvents

IFP Energies Nouvelles

8

Other CO2 capture process with LLPS

Ref.: Hu, 2010 Annual NETL CO2 Capture Technol. R&D Meeting. Lemaire, et al., 12th Intl. Network for CO2 Capture, 2009

Heat



Outline

Motivation

Concepts

Solvent performance


Summary

Amine selectionAbsorptionDesorptionChemical stability

9



Solvent performance IScreening tests – searching new amines

> 50 lipophilic amines (alkylamines)< 10 comparable to MEA or MDEACriteria

High loading capacity: > 0.7 mol/mol (20% CO2)Fast absorption rate: comparable to MEAGood regenerability: better than MDEALow degradability: comparable to AMP & MDEAModerate heat of reaction: lower than MEA

A: partially soluble in water, rapid absorption rateB: less miscible with water, high regenerability

Recommended absorbent: Solvent blend A+BA: as absorption activator e.g. DPA, A1

B: as regeneration promoter e.g. DMCA, EPDBlending A+B exploits the strengths of both components

N

HN

N

DPA

DMCA

EPD



Solvent performance II

Absorption

ReactivityRapid reaction rateComparable to MEA (when α<0.5)

Loading capacity (net)Alkanolamine 40-120 °C

w/ steam strippingTBS absorbent 30-80 °C

w/o steam strippingCO2 absorbed in TBS: 3.4 mol/kgHigher than MEA and AMP

mol

-CO

2/kg -

sol

0 20 40 60 80 100 120 140 1600,0

0,2

0,4

0,6

0,8

1,0

Load

ing

of C

O2 [m

ol C

O2 /

mol

am

ine]

Time [min]

A1

MEA

MDEA+MEA



Solvent performance III

Desorption

Liquid-liquid phase separation

Low regeneration temperatureca. 80°CLow value heat

High regenerability> 80% at 80°C for most TBS> 98% at 80°C for optimised TBS

Estimated energy consumption MEA: 4.0 GJ/t-CO2

TBS: 2.5 GJ/t-CO2

Before regeneration

During regeneration

After regeneration

Ref.: Geuzebroek, et al., TCCS-5, 2009



Solvent performance IV

Cyclic loading capacity

Higher CO2 loadingLower residual loading

Better than benchmarks

Chemical stability

Low temperature (80°C) for desorption less thermal degradationLow oxidability less oxidative degradation

B1 A1 MEA MDEA0

20

40

60

80

100

Perc

ent [

%]

Solvent

Basicity reduction by oxidative degradation Reactivity reduction by CO2 induced degradation Reactivity reduction by oxidative degradation Reactivity reduction by catalyzed oxidative degradation

B1 A1 MEA

DMX-1, 40°C A1+DsBA, 30°C A1+DsBA, 80°C MEA 30wt%, 40°C MEA 30wt%, 120°C

0 1 2 3 4 540

50

60708090

100

200

300

400

500

Loading (mol-CO2/kg-sol.)

PC

O2 (

mba

r)

Ref.: Raynal et al., 2010 (DMX-1 )



Outline

Motivation

Concepts

Solvent performance


Summary

Vaporisation lossPhase transitionRegeneration techniquesProcess development

14



Challenges and amelioration I

Amine vaporisation lossHigh volatilitySignificant volatile loss

Countermeasures

T for feed (top) at 30 °CReduced vaporisation

Hydrophobic solvent scrubbing

e.g. DiphylRecovery >80%

Water wash when using A1 as primary solvent

Reduced amine lossComparable to MEA or AMP

15

Amine Temp. Loss

°C %/day

A130 <0.540 1.8

DMCA30 4.840 12

DMCA+A1(3:1)

30 4.140 1050 14

MEA 40 1.2AMP 40 1.6



Challenges and amelioration II

Phase transition

Lower critical solution temperature (LCST): most lipo. Amines < 20°CProblem:biphasic solvent in absorber

Countermeasures

ConcentratingNegative on vaporisation lossLimited at 4M

Using more A1Negative on regenerationLCST ≈ 20°C

Partial deep regenerationResidual loading 0.1Increasing LCST to 30°C

Adding solubiliser<10wt%Increasing LCST to 40°C

16

3M(2:1) 3M(1:1) 4M(2:1) 4M(1:1)

0

10

20

30

40

50

emulsion

Tem

pera

ture

(°C

)

Concentration (mol/L)

PTT of DMCA+A1 with 9wt% AMP CST of DMCA+A1 with 9wt% AMP PTT of DMCA+A1 CST of DMCA+A1

Two phases

Single phase

emulsion

PTT: phase transition temperatureCST: critical solution temperature



Challenges and amelioration III

Challenges

Low temperature 80°CWithout steam

How to intensify theregeneration?

Regeneration intensification

+ Regeneration promoter

AgitationNucleationNucleation + Agitation

17

Regeneration techniques



Challenges and amelioration III

Agitation

Nucleation

18

Regeneration techniques

0 10 20 30 400,0

0,4

0,8

1,2

1,6

2,0

Des

orbe

r CO

2 (mol

/L)

Time (min)

750 rpm 500 rpm 250 rpm N

2 stripping

Solution: A1+B1, 2+1M at 75 °C

0 10 20 30 400,0

0,4

0,8

1,2

1,6

2,0

Des

orbe

r CO

2 (mol

/L)

Time (min)

1/40 wt. 1/60 wt. 1/80 wt. N2 stripping

Solution: A1+B1, 2+1M at 75 °C

none 100 rpm 250 rpm 500 rpm 750 rpm 1000 rpm Stripping0

50

100

150

200

250

CO

2 rele

ase

rate

[g/L

/hr]

Method

DMCA+A1 DMCA+DPA

Agitati

on

Stirring

Porous particles for CO2 bubble

formation



Challenges and amelioration IV

Process development

19

Regeneration w

ithoutsteam stripping

Flow sheeting diagram



Challenges and amelioration V

Bench-scale experimentation in packed absorption columns

20

Absorber

Bottom of absorber

Regenerator

At TU DortmundAt Shell G.S.



Summary

Novel absorbent: lipophilic amine TBS

Rapid absorption rate (due to activator A)High regenerability (due to regeneration promoter B)Excellent net CO2 loading capacityLow energy requirement High chemical stability

Novel concept: phase transition

LLPS enhanced regenerationRegeneration at 80°C use of waste heat reduces CO2capture process costs



Acknowlegement

Improvement of lipophilic-amine-based thermomorphic biphasic solvent

for energy-efficient carbon capture

CO2 Capture Research Group:

Prof. Dr. David W. AgarM.Sc. Jiafei Zhang TU Dortmund University

Dr. Frank GeuzebroekIr. Mark Senden Dr. Xiaohui Zhang Shell Global Solutions Int. B.V.

Technical Staff:Michael SchlüterJulian GiesJerzy Konikowski

Students:Robert Misch, Jing ChenYu Qiao, Wanzhong Wang Onyekachi Nwani

Trondheim

15.06.2011



End

Jiafei ZHANG

Emil-Figge-Str. 66 (TCB)D-44227 Dortmund, GermanyTel.: (+49) 231 - 755 2582 E-Mail: [email protected]/tcb

ThankThank youyouforfor youryour attentionattention

Campus of TU DortmundTCB

improvement of lipophilic-amine-based thermomorphic .... technical chemistry b prof. dr. david w....

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