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Home , Catalysis

CHEM-E1130 Introduction to catalysis

Prof. Riikka Puurunen 14.1.2018 Contents

1. Definition of catalysis and catalyst 2. Classification of catalysts 3. Seven steps of a heterogeneously catalyzed reaction 4. Catalysis: a tool for manipulating selectivity 5. Significance of catalysis? 6. Components of a heterogeneous catalyst 7. Engineering features of a solid heterogeneous catalyst + Conclusion & take-home message Definition of catalysis and catalyst Definition of ”catalysis”?

• IUPAC Gold Book, Compendium of Chemical Terminology • https://goldbook.iupac.org

• ”Catalysis: The action of a catalyst”

• Merriam-Webster: “a modification and especially increase in the rate of a induced by material You can also check: unchanged chemically at the end of the reaction”

4 Definition of ”catalyst”?

• IUPAC:” A substance that increases the rate of a reaction without modifying the overall standard Gibbs energy change in the reaction ” • Richardson: A catalyst is a substance that increases the rate at which a chemical reaction approaches equilibrium without itself becoming permanently involved in the reaction

• You can look also in: Oxford English Dictionary, Merriam- Webster

Richardson, Principles of Catalyst Development, Plenum Press, 1989.

5 In other words, a catalyst:

1. Increases the chemical 2. Does not influence the position of thermodynamic equilibrium 3. Is not (permanently) changed in the catalysed reaction

•

6 Timeline of catalysis Jöns Jacob From to Berzelius, … - 1834 seminal From empirics to science work 1835 1835-1897 The birth of industrial catalysis 1898-1918 The increase in global mobility by developing catalytic fuel processes https://dx.doi.org/10.1023/A:1025001809516 1919-1945 From war to peace 1946-1970 Environmental catalysis 1970-20?? J. J. Berzelius 1835

• Berzelius coined the word catalysis, combining the Greek words 휅훼휏훼´ (down) and 휆휐𝜎휄𝜍 ´ (solution, loosening).

• In Chinese, catalyst = a marriage broker [Cuīhuàjì]

催化剂 You can also check:

More, e.g.: http://dx.doi.org/10.1002/9781119181286 Ross, , Chapter 1, Figure (daguerrotype): https://en.wikipedia.org/wiki/J%C3%B6ns_Jacob_Berzelius Wikipedia: Jöns Jacob Berzelius (1779-1848) 8 Catalyst introduces a less difficult path for to follow

Grey: uncatalyzed

Green: catalyzed

 Energy Energy

Reaction 

9 Catalyst introduces a less difficult path for molecules to follow

Grey: uncatalyzed

Green: catalyzed  New reaction

intermediate Energy Energy

Reaction 

10 Catalyst introduces a less difficult path for molecules to follow Example: synthesis,

Haber-Bosch process Energy

Reaction 

Richardson, Principles of Catalyst Development, Plenum Press, 1989, p. 2.

11 Catalyst introduces a less difficult path for molecules to follow Example: ammonia synthesis, Haber-Bosch process

Energy • Exothermic reaction • Catalyst does not change the overall energetics • energy:

Ehomogeneous >> Ecatalytic Reaction 

Richardson, Principles of Catalyst Development, Plenum Press, 1989, p. 2. Also: https://www.chemguide.co.uk/physical/equilibria/haber.html 12 Interactions between catalyst & should be not too storng nor too weak but ”just right” (Sabatier)

Volcano curves often encountered. There, measure of catalytic activity… • Reaction rate • Turn-over frequency (TOF) • etc … plotted against a measure of binding energy

More, e.g.: http://dx.doi.org/10.1002/9781119181286 Richardson, Principles of Catalyst Development, Plenum Press, 1989 Classification of catalysts Typically divided to homogeneous vs heterogeneous catalysis

1. Homogeneous: catalyst is in the same as reactants (and products) • -gas, -liquid, solid-solid 2. Heterogeneous: reactants and catalyst in a different phase • Phase not only solid, liquid, and gas, but also immiscible , e.g. oil and . • Most often: solid catalyst with gaseous and/or liquid reactant 3. form their own (biocatalyst) group (will not be dealt further in this course) (4. Photocatalysts, will not be dealt with further in 2018-2019) More: Ross book, Chapter 1, Box 1.1

15 Some examples

1. Homogeneous catalysts: most typically liquids. Examples: • Liquid-liquid: of by (more examples to follow in this coures)

• Vapor-vapor: oxidation of SO2 by NO2 - • Solid-solid: decomposition of (K+ ClO3 ) by MnO2

2. Heterogeneous catalysts: most typically . Examples

• NH3 process; many more examples to follow during course Seven steps of a heterogeneously catalyzed reaction Seven steps of a heterogeneously catalyzed reaction

1. External 2. Internal diffusion 3. 4. Surface reaction 5. Desorption of 6. Internal diffusion of product 7. External diffusion of product

Figure 4.1: Julian Ross: Heterogeneous Catalysis - Fundamentals and Applications, © Elsevier 2012. Link to electronic book here. Catalysis: a tool for manipulating selectivity Catalyst: tool for selectivity. Case: synthesis gas H2 + CO

Paraffinic

H2 + CO [Co/ThO2] , , and acids

Methanol

Richardson, Principles of Catalyst Development, Plenum Press, 1989, p.5.

20 Catalysis: tool of

Anastas et al. Applied Catalysis A: General 221 (2001) 3–13, https://doi.org/10.101 6/S0926- 860X(01)00793-1 Significance of catalysis? Timeline Lead chamber Berzelius: “Catalysis” process, H2SO4 From alchemy to chemistry Ostwald: “there is probably no chemical reaction which … - 1834 can not be influenced From empirics to science catalytically” 1835-1897 The birth of industrial catalysis ”The problem” 1898-1918  NH3 synthesis Fluid Catalytic (Haber-Bosch) The increase in global Fischer-Tropsch mobility by developing catalytic fuel processes 1919-1945 industry & (& explosive automotive market) From war to peace 1946-1970 (1962 Rachel Carson’s Silent Spring) Environmental catalysis Pollution control 1970-20??

https://dx.doi.org/10.1023/A:1025001809516 How a centrury of ammonia synthesis changed the world, Erisman et al., Nature Geoscience 1 (2008) 636-639. ” dioxide crisis”, 2018

• Empty shop shelves in summer for beer & soft drinks (with Fifa World Cup!)

• Shortage of CO2 because of… • … shutdowns & maintenance in

NH3 production

https://www.chemistryworld.com/news/explainer-the-carbon-dioxide-crisis- /3009216.article, accessed 12.1.2019 Significance of catalysis?

Without catalysts, there would not be • Modern • Oil • production • Possibility to control emissions • Enough food for the earth’s population How large is the catalyst market?

• Market studies in 2013 have estimated the total sales of catalysts to be between $15 and $19 billion per year, and to rise 4−5% per year. • Munnik, de Jongh, de Jong, Recent developments in the synthesis of supported catalysts, Chem. Rev. 115 (2015) 6687. (Open Access) http://dx.doi.org/10.1021/cr500486u --> • https://www.transparencymarketresearch.com/global-refinery-catalyst-market.html • https://www.freedoniagroup.com/world-catalysts.html

• ~850 catalysts commercially available • Source: Prof. Jiri Cejka, plenary lecture at EuropaCat 2017

Munnik, de Jongh, de Jong, Recent developments in the synthesis of supported catalysts, Chem. Rev. 115 (2015) 6687. (Open Access) http://dx.doi.org/10.1021/cr500486u Components of a solid heterogeneous catalyst Three typical components of a solid heterogeneous catalyst

Richardson, Principles of Catalyst Development, Plenum Press, 1989, p. 27. Active component: chemical activity

Types, e.g.: • • Semiconductor and sulfides • Insulator oxides and sulfides

Richardson, Principles of Catalyst Development, Plenum Press, 1989, p. 27.

30 Transition metals are typical active components

Source: https://iupac.org/what-we-do/periodic-table-of-elements/ , 31 accessed 12.1.2019 https://en.wikipedia.org/wiki/Transition_metal, accessed 14.1.2019 Active component: chemical activity

• Types, e.g.: • Metals • Semiconductor oxides and sulfides • Insulator oxides and sulfides

Richardson, Principles of Catalyst Development, Plenum Press, 1989, p. 27.

32 Support: high surface area etc

• Function: • High surface area; Porosity • Mechanical properties; Stability • Dual functional activity • Modification of active component • Types, e.g.: • High melting point oxides • Clays • Carbon

Richardson, Principles of Catalyst Development, Plenum Press, 1989, p. 27.

33 Some catalyst supports

+ ZrO2, CeO2-ZrO2, TiO2, …

Richardson, Principles of Catalyst Development, Plenum Press, 1989, p. 31.

34 Catalysts contain ”finely disintegrated metals”

Dispersion defined as

• D = Ns / Nt • Ratio surface vs total atoms (typically used for metals)

Image: Ross, Heterogeneous catalysis, Chapter 3 (Fig. 3.5) Image: Richardson, Principles of Catalyst Development, Plenum Press, 1989, p. 31. More, e.g.: http://dx.doi.org/10.1002/9781119181286 Sabatier Nobel lecture 1912: https://www.nobelprize.org/prizes/chemistry/1912/sabatier/lecture/ 35 Distribution of surface sites varies with crystallite size

corner edge face

Image: Richardson, Principles of Catalyst Development, Plenum Press, 1989. Promoters:”spices” of a catalyst

• Function, on support: • Structural • Activity inhibition • Activity promotion • Function, on active component: • Electronic • Morphology • Poisoning

Richardson, Principles of Catalyst Development, Plenum Press, 1989, p. 27.

37 Examples of promoters

Typical: K basic Cl acidic

Richardson, Principles of Catalyst Development, Plenum Press, 1989, p.36.

38 Engineering features of a solid heterogeneous catalyst Engineering features of a catalyst

Richardson, Principles of Catalyst Development, Plenum Press, 1989, p. 24.

40 Engineering features of a catalyst

Deactivation mechanisms

Richardson, Principles of Catalyst Development, Plenum Press, 1989, p. 24.

41 Texture parameters of a solid catalyst Specific surface areas vary from ~10 to ~1000 m2/g

Richardson, Principles of Catalyst Development, Plenum Press, 1989, p. 11.

42 Many shapes and sizes

http://www.oxeeco.in/sites/default/files/images/catalysts2.jpg

43 Conclusion & take-home message Take-home message, 1st lecture

• You know the definition and understand the significance of catalysis • This was the first lesson to learn to ”speak the language of catalysis”. Field-specific words encountered.

Next lecture • Timeline of industrial catalysis, three significant historical examples, more ”language of catalysis” • Adsorption excercise will be shared Extra slides • More on market research Extra: More on a market research https://www.freedoniagroup.com/world-catalysts.html (Aalto does not own this report) • Openly available information: • World demand for catalysts will grow 4.8 percent per year to $20.6 billion in 2018. Growth will be led by a rebound in the chemical and polymer industries, most notably in developed economies hit hard by the recession. The fastest advances, however, will occur in developing areas such as the Asia/Pacific and Africa/Mideast regions. • This study analyzes the $16.3 billion world catalyst industry. It presents historical demand data (2003, 2008 and 2013) and forecasts (2018 and 2023) by material (e.g., metals, organometallic materials, chemicals, , enzymes), product (e.g., , oxidation, synthesis gas, , hydroprocessing, , , Ziegler-Natta, reaction initiators), market, (e.g., , refining, polymerization), world region, and for 18 countries. • The study also considers market environment factors, details industry structure, evaluates company market share and profiles 34 industry players, including BASF, WR Grace, and . ”Everything is a catalyst for something”

Quoted in: James T. Richardson, Principles of Catalyst Development, 1989 (p. 49)

Source: https://twitter.com/openculture/status/840318207667785728