Novel Reaction Engineering Concepts for Catalyst Immobilisation in

HydroformylationDavid Cole-Hamilton

Simon DessetSasol (Doug Foster)

Ulrich HintermaierIDECAT

Catherine SantiniCPE Lyons

Mark MuldoonSt. Andrews

HydroformylationR

CHO

R

OHC

R

CH2OH

R

HOH2C

+ Aldehydes

+ Alcohols

+ CO + H2

branchediso

(b)

linearnormal

(l)

R

100 % atom economyLiquid and gaseous substratesIssues of SelectivityProblems with product separationIndustrially very important

C9 – C14 1.5 M tonnes y-1

Plasticisers, soaps, detergents

O

OSO3Na

NOBS - initiator for cold water bleach

CelaneseEastman

Hydroformylation ConditionsParameter Cobalt /(+phosphine)

Temperature / oC

Pressure / bar

l:b

Side reactions

120-160 (150-190)*

270-300 (40-100)

3:1 (10:1)

Alkanes, alcohols,esters, acetals

Rhodium

80-120

12-25

12:1

Condensed aldehydes(used as solvent)

Stability

Catalyst recovery

Stable to high T

Difficult but possible

Decomposes at 110 oC

Easy <C7

* Rate is reduced by a factor of 4-6

Boiling pressures of aldehydes at 110 oC

0

5

10

15

20

25

30

35

40

45

8 10 12 14 16 18

Aldehyde chain length

Vap

our p

ress

ure

at 1

10 C

/ to

rr

Problems with Homogeneous Catalysts

• - Separation of the solvent, catalysts and product

• - Recycling of the catalyst

• - The use of volatile organic solvents

• - Batch or batch continuous processing

Batch Continuous

Dissolved solidsLiquidsGasesHomogenousHeterogeneousLiquid (solvent)

Continuous flowIntegral separation

Advantages

Some catalyst is outside the reactorPrecipitation )may occurDecomposition)

Disadvantages

Reactants

Catalyst

PhaseCSTR

FlashColumn

or Phase

Separator

Catalyst recycle

Substrates

Products

Methanol Acetic acidBiphasic reactions

Uses

Recycling Homogeneous Hydroformylation Catalysts

Supported catalysts• Insoluble supports• Soluble polymers• Dendrimers

Biphasic systems• Aqueous - Organic• Fluorous - Organic• Ionic liquid - Organic• Supercritical fluid• Supercritical fluid - Ionic Liquid• Supercritical fluid - Organic

Hybrid systems• Supported aqueous phase• Supported ionic liquid phase• Supported ionic liquid phase with supercritical flow

Also:D. J. Cole-Hamilton, Science, 2003, 299, 1702

Hydroformylation used as an example

Separation, Recovery and Recycling in Homogeneous CatalysisChemistry and Process DesignEds D. J. Cole-Hamilton (St. Andrews) and R. P. Tooze (Sasol)

CHAPTER 1 HOMOGENEOUS CATALYSIS – ADVANTAGES AND PROBLEMSD. J. COLE-HAMILTON AND R. P. TOOZE

CHAPTER 2 CLASSICAL HOMOGENEOUS CATALYST SEPARATION TECHNOLOGYD. R. BRYANT

CHAPTER 3 SUPPORTED CATALYSTSJ.N.H. REEK, P.W.N.M. VAN LEEUWEN , A.G.J. VAN DER HAM AND A.B. DE HAAN

CHAPTER 4 SEPARATION by SIZE-EXCLUSION FILTRATIONN.J. RONDE AND D. VOGT

CHAPTER 5 BIPHASIC SYSTEMS: WATER – ORGANICE. WIEBUS AND B. CORNILS

CHAPTER 6 FLUOROUS BIPHASIC CATALYSISC. R. MATHISON AND D. J. COLE-HAMILTON

CHAPTER 7 CATALYST RECYCLING USING IONIC LIQUIDSP. WASSERSCHEID, M. HAUMANN

CHAPTER 8 SUPERCRITICAL FLUIDSC. M. GORDON AND W. LEITNER

CHAPTER 9 AREAS FOR FURTHER RESEARCHD. J. COLE-HAMILTON AND R. P. TOOZE

SPRINGER, Dordrecht, 2006

What we would likeContinuous flow Homogeneous Catalysis

Advantages SimpleContinuous flowBuilt in catalyst/product separationCatalyst under optimum conditions

Disadvantages Substrates and product must be volatileSolvent and catalystinvolatile

Hydroformylation of propene

Phases Liquid (involatile solvent)

Reagents Volatile liquidsGases

Catalyst HomogenousHeterogeneous

SubstratesProducts

Supported catalystsMetal leaching into solution is usually a problem

O

N

SiOOO

Ph2P

PPh2RhCOOC

H

R + CO + H2R

CHO

A. J. Sandee, J. N. H. Reek, P. C. J. Kamer, P. W. N. M. van Leeuwen, J. Am. Chem. Soc., 2001, 123, 8468

Rotocat

1 year no loss in activity / selectivity

TOF 287 h-1

l:b 40Rh < 0.1 mg mol ald-1

Dendrimers

2.5 nmsolvent

products1.5 nm

Micro ormesoporous solidmembrane

Hydroformylation of Oct-1-eneCO + H2

Toluene

O

O

+

SiPPh2

PPh2 8

[Rh(CO)2(acac)], 120 oC, 10 bar

P:Rh

l:b

6

1.213.9

4 x 10-3 mol dm-3

k / 10-3 s-1

Nonanal % 86

6

3.8All isomeric aldehydesobserved

3.0

Si

PPh2

PPh2

MeMe

73

L. Ropartz, K.J. Haxton, D.F. Foster, R.E. Morris, A.M.Z. Slawin and D.J. Cole-Hamilton, J. Chem. Soc., Dalton Trans., 2002, 4323

Aqueous biphasicVent

Propene

CO/H2

Stri

pper

Dis

tilla

tion

Rea

ctor

Decanter

iso-

n-

1

2

3

4

56

Ruhrchemie/Rhône Poulenc Process

P

NaO3S

SO3Na

SO3Na

Vent

Propene

CO/H2

Stri

pper

Dis

tilla

tion

Rea

ctor

Decanter

iso-

n-

1

2

3

4

56

Ruhrchemie Reactor

Only operational for propeneLow solubility of higher alkeneslimits mass transfer

< 1 ppb Rh loss

E. Wiebus and B. Cornils in Catalyst separation, recovery and recycling: Chemistry and process Design, Eds D. J. Cole-Hamilton and R. P. Tooze, Springer, Dordrecht, 2006, p 105

[Rh(acac)(CO)2] / P(C2H4C6F13)3

TOF 890 h-1

Good retention into fluorous phaseLoss of 4.2 % Rh over 9 runsGreater loss of phosphine

l:b ratio low unless v. high P loading152 mmol dm-3 l:b = 6.3304 mmol dm-3 l:b = 7.8Linear selectivity - ca 75 %8-9 % isomerisation

CatalystFluorous solvent

Substrate(Organic solvent)

CatalystFluorous solvent

Product(Organic solvent)Homogeneous

Reaction occurs

HEAT COOL

Fluorous biphasic

I. T. Horvath, G. Kiss, R. A. Cook, J. E. Bond, P. A. Stevens, J. Rabai, and E. J. Mozeleski, J. Am. Chem. Soc., 1998, 120, 3133.

Continuous Catalysis in the fluorous phase

Clare Mathison Yulin Huang Evangelia PerperiGeorge Manos (UCL)

Continuous Flow Reactor

E. Perperi, Y. Huang, P. Angeli, G. Manos, C. R. Mathison, D. J. Cole-Hamilton, D. J. Adams and E. G. HopeChem. Eng. Sci. 2004, 59, 4983

Flow rate = 1 cm3 min-1 1.2 L of octene consumed

Continuous operation

0.00

10.00

20.00

30.00

40.00

50.00

60.00

00:00 02:24 04:48 07:12 09:36 12:00 14:24 16:48 19:12 21:36

Time / h

Con

vers

ion,

%

nonanal

isomerised alkene

l:b

branched aldehyde

Phosphine leaching

[HRh(CO)4]

Rh leaching

Phosphine leaching

Increased rate

> 15,000 turnoversaverage 750 h-1

Octene hydroformylation in perfluoromethylcyclohexaneRh / P(C6H5C6F13)3

Ionic liquid

O N

NN

N

OP

OP

+ +5 5

[PF6]2

N N+PF6

[BMIM]PF6TOF 6,200 h-1

l:b 40Rh < 5 ppbP < 100 ppb

13 step synthesis

R. P. J. Bronger, S. M. Silva, P. C. J., Kamer and P. N. W. M. van Leeuwen, P., Dalton Trans. 2004, 1590

Supercritical Fluids

Pressure

Temperature

Heat a liquidDensity falls

Compress a gasDensity rises

Critical pointDensity of gas and liquid are equal

73.8bar

31.1 oCCarbon Dioxide

solid liquid

gas

Supercritical fluid

Supercritical Fluids

Solid in solution

Like a gas - fills all space availableLike a liquid - dissolves things

To supercritical solutionEvaporate liquid

• - Potential for use as transport vector in continuous flow systems

CESS

CO H2

Cat*

High pressure scCO2 Low pressure scCO2

Cat*

Gaseous CO2

Diagram after D. J. Cole-Hamilton, Adv Syn. Catal., 2006, 348, 1341

O

O

O

Method: S. Kainz and W. Leitner, Catalysis Letters, 1998, 55, 223

PC6F13 3

Catalysis and extractions using supercritical solutions

R101

CO2

C101 C102

P101

C103

S101

P102

P103

C104

V101

C105

1-octene

syngas

catalystE102E101

E103

E104

E105

product

P1T1

P2T2

P3T3

ReactorCatalystseparator Product

separator

C. M. Gordon, W. Leitner, in Catalyst separation, recovery and recycling: Chemistry and process Design, Eds D. J. Cole-Hamilton and R. P. Tooze, Springer, Dordrecht, 2006, p 105

Continuous flow reactor for low volatility substrates and products

Substratesin scCO2

Productsin scCO2

Liquid catalystor

Catalyst in involatile solventSolvent• - Involatile• - Insoluble in scCO2• - Dissolves catalyst

Catalyst• - Soluble in solvent• - Insoluble in scCO2

IONIC LIQUID? IONIC CATALYST

Suprecritical fluid – ionic liquid reactor design

CO/H2

Liquid Pump

Regulator

Gas Booster

Dosimeter

Liquid Pump CompressionDecompression

Reaction

Expansion Valve

Expansion Valve

Flow meter

Collection Vessels

Reactor

Supercritical fluid ionic liquid

[Rh(CO)2acac] - 15 mmol dm-3

L - 233 mmol dm-3

IL - 12 cm3

T - 100 OCptot - 200 bar

Total flow rate - 0.6-1.9 NL min-1

CO:H2 - 1:2CO:substrate - 20-5:1pcollection - 3-5 bar

[PMIM][Ph2PC6H4SO3] (L)

TOF / h-1 l:b Rh loss / ppb 517 3.1 12 272 40 200

O

N

PPh2 PPh2

N N

Cl-

N N+[N(SO2F)2]-

[OMIM][Tf2N]

Supercritical fluid

R

COH2

scCO2

(ionic) catalystproduct mixture

ProductsscCO2

CO2 (g)

R

R CHO

OHC

Continuous flow – no ionic liquid

Rh / [octMIM][Ph2P(C6H4SO3)]100 oC140 bar

239 h-1

Catalyst dissolved in nonanal at start

P. B. Webb and D. J. Cole-Hamilton, Chem. Commun., 2004, 612

Process synthesisCO2 contains CO and H2

CO2

FeedTank

Reactor Separator

40-60 bar

100 bar 70 bar

liquefier40-60

bar

Product

Alkene / liquid CO2 recycleAlkene feed

Gas recycle

compressor

Gas feed

P. B. Webb, T. E. Kunene and D. J. Cole-Hamilton, Green Chemistry, 2005, 7, 373-379

Supported liquid phase catalysis

SILP catalystparticle

support

Porousnetwork

substratephase

L RhLL

CO

H

reactantsproducts

support

support

Immobilisedcatalytic IL-phase

++ ++++

++ ++++______

__

__

__

+ _ = ionic liquid++ __ = ionic liquid= ionic liquid or water

Water : Davies, M. E., in Aqueous-phase organometallic catalysis, edited by B. Cornils, and W. A. Herrmann, Wiley-VCH, Weinheim, 1998, p 241

IL: C. P. Mehnert, R. A. Cook, N. C. Dispenziere, and M. Afeworki, J. Am. Chem. Soc., 2002, 124, 12932;

A. Riisager, K. M. Eriksen, P. Wasserscheid, and R. Fehrmann, Catal. Lett., 2003, 90, 149

Can be run in continuous flow mode using a tubular reactor.

Good for propene(gas phase)Rate falls with time as a result of fouling by aldol condensation products

Problem with aqueous biphasic systems

1-octene

1-hexene

1-pentene

Low alkene solubility in water makes mass transport rate limiting

Thermoregulated catalysis

CatalystWater

Substrate(Organic solvent)

CatalystWater

Product(Organic solvent)HEAT COOLSubstrate

Catalyst(Organic solvent)

Water

P O

3OHn

X. L. Zheng, J. Y. Jiang, X. Z. Liu, and Z. L. Jin, Catal. Today, 1998, 44, 175A. Behr, G. Henze and R. Schomäcker, Adv.Syn. Catal. 2006, 348, 1485

TOF 182 h-1

Use of additivesAnionic rhodium complexCationic phase transfer catalysts lead to increased leachingCationic surfactants leads to emulsification (slow phase separation)

N N+Br-

Simon Desset Sasol

[OMIM]Br

Hydroformylation of long chain alkenes

1-octene

1-hexene1-decene + [OMIM]Br

1-pentene1-octene + [OMIM]Br

1-hexene + [OMIM]Br

[OMIM]Br 0.5 mol dm-3

Gas transport limited

Addition of [OMIM]Br

0.492711.53.3294.65080.5

126.2784.42.7894.710400.5

n.d.25.623.943.451000

Rhleaching(ppm)

TOF (h-1)l/bConversion (%)

P/Rh[OMIM]Br/ P

[OMIMBr] / (mol dm-3)

P/Rh 10, no additive

P/Rh 50, [OMIM]Br

P/Rh 10, [OMIM]Br

Problems with supported liquid phase catalysis

SILP catalyst

particle

support

Porousnetwork

substratephase

L RhLL

CO

H

reactantsproducts

support

support

Immobilisedcatalytic IL-phase

++ ++++

++ ++++______

__

__

__

+ _ = ionic liquid++ __ = ionic liquid

Rate dependent on film thickness:Too thin, substrate interferes with catalyst moleculesToo thick, mass transport becomes dominant

For liquid phase reactions:

The supported liquid (IL or water) can be removed by dissolving or mechanical loss (can also lead to loss of catalyst)

Gas transport to the catalyst is very slow (only the initially dissolved gas is available)

Supported ionic liquid phase catalysis with supercritical transport

Diffusion is gas like so gases and substrate can reach catalyst phaseSupercritical fluids increase solubility of gases in IL

M. Solinas, A. Pfaltz, P. G. Cozzi, and W. Leitner, J. Am. Chem. Soc., 2004, 126, 1614

Ulrich HintermairIDECAT

Guoying ZhaoRTN Supergreen Chemistry

Catherine SantiniCPE Lyons

N NPh2P

SO3-

+N N+

[N(SO2F)2]-

octene

Product

Preheating coil

Reactor

CO2COH2

SILP-SCF ReactorDosimeter

Hplc pump

scCO2

Compressor

Solid phase reactor

Effect of reacton parameters SILP-SCF (100 bar, 100 oC)

Total conversion

05

101520253035404550556065707580859095

100

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0

Time [h]

Con

v. [%

]

UH 10 (14wt%)UH 12 (44wt%)UH 11 (28wt%)

0.24. 0.12Substrate flow / cm3 min -1

0.12 0.360.24

Turnover frequencyTurnover frequency

0.0

100.0

200.0

300.0

400.0

500.0

600.0

700.0

800.0

900.0

1000.0

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0

Time [h]

TOF

[h-1

]

14wt% IL44wt% IL29wt% IL

Catalyst stability

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

20000

0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0Time / h

Cat

alys

t tur

nove

rs

TOF = 500 per h

Aldol condensation products removed by sc CO2

P, S, E(P, E)

nr0.002 (0.03)

76 (92)3.1(40)

7.8 (4.1)

517 (272)

100200ScCO2 / Ionic liquid

E, I< 0.06< 0.00385445.3620010060Ionic liquidR, Snr.014-0.07753.22.5162100125ScCO2

Pnr< 0.17795.514.243065200ScCO2

E, L160.08816.38.844007020Fluorousbiphasic

0.07723.371110020Aqueous

R, S?nrnrnrnr0.318210050Thermo-regulated

R, Lnr2092 (b)0.050.03254567Supported Dendrimer VAM

Unrnr8613.97.1179212010Dendrimer

R, S?, Lnr0.3nrnr0.031608030Soluble polymerc

835.30.844411016Homo (propene)

ProblemP lossa

mg (mol prod)-1

Rh lossmg (mol prod)-1

Linear aldehyde / %

l:bRate / mol dm-3 h-1

TOF / h-1

T / oC

p / bar

System

nr< 0.195400.122878050Supported

R, Pnr< 1.2943316090170Supported / scCO2

S

R = rate, P = pressure, S = selectivity, U = ultrafiltration, L = leaching, E = expense, I = isomerisation

R, E?nrnr723.2800100100Supported IL/scCO2

Conclusions

• Very many different methods for catalyst recycling are being developed

• None has so far been commercialised• Supported or ionic liquids look the most

promising• New advances in additives for aqueous biphase

look promising• Supported ionic liquid phase with sc flow is very

exciting

Catalyst dissolved in ionic liquid or in product/substrate mix