Homogeneous Catalysis A part of 529-0502-00L Catalysis Jeroen A. van Bokhoven, Marco Ranocchiari 1
Homogeneous Catalysis
A part of 529-0502-00L Catalysis
Jeroen A. van Bokhoven, Marco Ranocchiari
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Dr. Marco Ranocchiari
Laboratory for Catalysis and Sustainable Chemistry (LSK) OSUA/2045232 Villigen PSI Switzerlandemail: [email protected] tel: +41 (0)56 310 58 43
Fr, 10.45 – 11.30 HCI J 7
Prof. van BokhovenWe, 9.45-11.30 HCI J4
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Topics:1. Basic Concepts
Catalysis, Oxidative addition, reductive elimination, migratory insertion, elimination
2. Reactions with COa. Hydroformylation (Rh, Co, Ir) (including asymmetric hydroformylation)b. Carbonylation of alcohols (Monsanto Process)
3. Reactions with Olefinsa. Olefin oxidationb. Wacker process (olefin hydration)c. Carbene complexesd. Polymers by Metathesise. The Shell Higher Olefins Process (SHOP)
4. Homogeneous, heterogeneous and MOF catalystsa. Differences between homogeneous and heterogeneous catalysis (slides and script)b. Metal-organic frameworks (MOFs) - slides
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Learning Material and Books
Scripthttp://www.vanbokhoven.ethz.ch/education/catalysis.html
Basics:R. H. Crabtree, The Organometallic Chemistry of the Transition Metals, Wiley, 2009
Industrial Processes:G. P. Chiusoli, P. M. Maitlis, Metal-catalysis in Industrial Organic Processes, RSC Publishing, 2008
Industrial perspective with some details on the chemistry:S. Bhaduri, D. Maitlis, Homogeneous Catalysis - Mechanisms and Industrial Applications, Wiley, 2000
Details on homogeneous catalysts:Piet W. N. M. van Leuween, Homogeneous Catalysis - Understanding the Art, Kluwer Academic Publishers
Online:Catalysis - An Integrated Approach to Homogeneous, Heterogeneous and Industrial CatalysisEdited by: J.A. Moulijn, P.W.N.M. van Leeuwen and R.A. van Santen
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The EXAM
30 min Oral Exam
20 min heterogeneous10 min homogeneous, overlap and MOF catalysts
The GOALS
- Understanding and discussing catalytic processes based on homogeneous complexes
- Understanding and learning catalytic cycles of transition metal molecular catalysts
- Understanding the differences between homogeneous and heterogeneous catalysts and supported molecular catalysts.
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AMMONIA SYNTHESIS
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3/2H2+1/2N2 NH3
• "detonator of the population explosion"
• produces 450 million tonnes of nitrogen fertilizer per year
WithoutCatalyst
WithCatalyst
ΔH
reaction coordinate
METATHESIS OF OLEFINS
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Catalysis is a phenomenon related to kinetics!A Catalyst opens a new reaction pathway:
The equilibrium position is determined by by thermodynamic parameters of the reaction and NOT by the presence of the catalyst (ΔG0 < 0 → K > 1).
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Heterogeneous CatalysisC2H4 + H2 C2H6
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Pt surface! →!!!!
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THE IMPORTANCE OF CATALYSIS80% of all materials you see in your everyday life have seen at one point or another a catalystHETEROGENEOUS CATALYSTS
source: http://www.essentialchemicalindustry.org/processes/catalysis-in-industry.html
Process Catalyst Equation
Making ammonia Iron
Making synthesis gas (carbon monoxide and hydrogen)
Nickel
Catalytic cracking of gas oil Zeolite Produces:a gas (e.g. ethene, propene)a liquid (e.g.petrol)a residue (e.g. fuel oil)
Reforming of naphtha Platinum and rhenium on alumina
Making epoxyethane Silver on alumina
Making sulfuric acid Vanadium(V) oxide on silica
Making nitric acid Platinum and rhodium
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ZEOLITE CATALYSTS
source: http://www.essentialchemicalindustry.org/processes/catalysis-in-industry.html
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Process Catalyst Equation
Catalytic cracking of gas oil Zeolite Produces: a gas (e.g. ethene, propene) a liquid (e.g.petrol) a residue (e.g. fuel oil)
Reforming of naphtha
Platinum and rhenium on zeolite
Disproportionation of methylbenzene Zeolite
Dealkylation of methylbenzene Zeolites
Making cumene (1-methylethyl)benzene< Zeolite (ZSM-5)
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HOMOGENEOUS
source: http://www.essentialchemicalindustry.org/processes/catalysis-in-industry.html
Manufacture Catalyst Equation
Ethane-1,2-diol Sulfuric acid
2,2,4-Trimethylpentane (iso-octane)
Hydrogen fluoride
Phenol and propanone Sulfuric acid
Bisphenol A Sulfuric acid
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HOMOGENEOUS Transition Metal-CatalyzedManufacture Catalyst Equation
Linear aldehydes from olefins (Hydroformylation of olefins)
Co/Rh molecular complexes
Acetic acid Rh and Ir with promoters CH3OH + CO → CH3COOHPolycyclopentadiene (metathesis) WCl6/WOCl4/Et2AlCl (Metton)
Polypropylene Titanocenes with MAO CH2=CH2-CH3 → [CH2–CH2]n | CH3
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HYDROFORMYLATION OF OLEFINS
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Active site in the MOF*:
Linear :branched ratio determined by:- Steric hindrance (the reaction
is under kinetic control)
*This active site has already been synthesized for topology MIL-101(Al)
Question: Can we predict which functional
group/MOF should we have within the environment around the active site to improve linear/
branched ratio?
Reaction:
We hope that computations will give the
answer
R1+ CO + H2 R1
CHO R1
CHO+
linear branched
PPh2O
O
O
O
MOF
MOF
RhOC
COOCH
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Challenges in Catalysis
Photocatalytic water splitting for hydrogen production
CO2 reduction
Selective methane activation
Understand how to design catalyst structures to control catalytic activity and selectivity
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