Heterogeneous catalysis
| Technology | |
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| Technology details | |
| Name: | Heterogeneous catalysis |
| Category: | Conversion (Chemical processes and technologies) |
| Feedstock: | Wide range |
| Product: | Wide range |
Heterogeneous catalysis is a catalysis in which the catalyst and the feedstock are in different phases. In practice, this often means that the feedstock is a liquid or gas and the catalyst is a solid, also known as solid catalysis. Heterogeneous catalysis is the most widely used form of catalysis in the current chemical industry.[1] There is a wide variety of catalytic systems and many reactions can be catalysed with a solid catalyst. Examples are pyrolysis, hydro-processing, oxidation, amination, dehydration, hydrolysis, (trans)esterification, and isomerisation.[2] Common heterogeneous catalysts are heterogeneous solid base catalysts and heterogeneous solid acid catalysts.[3]
Feedstock
Origin and composition
Due to the wide range of available catalysts and the large spectrum of reactions they can catalyse, the feedstock range for heterogeneous catalysis is significant. This ranges from biomass feedstocks such as lignocellulose, lignin, cellulose, sugars, and fatty acids, to products derived from biomass, such as glycerol and furfural.[2]
Pre-treatment
The pre-treatment of the feedstock for a heterogeneous catalysis is depending on the specific process and feedstock used. In principal, the feedstock normally is a liquid or gas so for solid feedstocks a conversion process like a pyrolysis or gasification or a solution is needed.
Process and technologies
A wide range of processes and technologies can make use of heterogeneous catalysts. Examples are pyrolysis, hydro-processing, oxidation, amination, dehydration, hydrolysis, (trans)esterification, and isomerisation.[2] The most common heterogeneous catalysts are heterogeneous solid base catalysts and heterogeneous solid acid catalysts. Base catalysts have a high concentration of basic sites that ensure the catalytic activity, often from Ba, Ca, Mg, and Sr and can be mixed or doped. Soap formation is a recurring drawback of these systems. Acid catalysts get their activity either from Brønsted or Lewis acidity and are commonly zirconia, silica, zeolites or zeotype materials. Major advantages of heterogeneous catalysis is the ease of separation, recyclability and high selectivity.[3] Current development for future heterogeneous catalytic systems are in metal-organic frameworks (MOFs), magnetic catalysts, and solid phase ionic liquids.[2]
Some large-scale industrial processes incorporating heterogeneous catalysts are listed below:[4]
| Process | Reactants, Product/s (not balanced) | Catalyst | Comment |
|---|---|---|---|
| Sulfuric acid synthesis (Contact process) | SO2 + O2, SO3 | vanadium oxides | Hydration of SO3 gives H2SO4 |
| Ammonia synthesis (Haber–Bosch process) | N2 + H2, NH3 | iron oxides on alumina (Al2O3) | Consumes 1% of world's industrial energy budget |
| Nitric acid synthesis (Ostwald process) | NH3 + O2, HNO3 | unsupported Pt-Rh gauze | Direct routes from N2 are uneconomical |
| Hydrogen production by Steam reforming | CH4 + H2O, H2 + CO2 | Nickel or K2O | Greener routes to H2 by water splitting actively sought |
| Ethylene oxide synthesis | C2H4 + O2, C2H4O | silver on alumina, with many promoters | Poorly applicable to other alkenes |
| Hydrogen cyanide synthesis (Andrussov oxidation) | NH3 + O2 + CH4, HCN | Pt-Rh | Related ammoxidation process converts hydrocarbons to nitriles |
| Olefin polymerization Ziegler–Natta polymerization | propylene, polypropylene | TiCl3 on MgCl2 | Many variations exist, including some homogeneous examples |
| Desulfurization of petroleum (hydrodesulfurization) | H2 + R2S (idealized organosulfur impurity), RH + H2S | Molybdenum-Cobalt on alumina | Produces low-sulfur hydrocarbons, sulfur recovered via the Claus process |
Product
Heterogeneous catalysis is widely used throughout chemistry and a plethora of products can be made. Heterogeneous catalysis is often used in the production of biodiesel[3], but can also be employed in the pyrolysis process or in the production of many other value added chemicals.[2]
Post-treatment
The post-treatment of the products of a heterogeneous catalysis is depending on the specific process and final products aimed for.
Technology providers
| Company name | Country | Technology category | Technology name | TRL | Capacity [kg/h] | Catalyst | Temperature [°C] | Feedstock: Food waste | Feedstock: Garden & park waste |
|---|---|---|---|---|---|---|---|---|---|
| Johnson Matthey | United Kingdom | Conversion (Chemical processes and technologies) | Heterogeneous Catalyst | 9 | - | Various options (Pd, Pt, Rh, Ru) | - | ● | ● |
| Topsøe Renewables | Denmark | Conversion (Chemical processes and technologies) | HydroFlexTM | 6-7 | - | Various available (e.g. noble-metal, base-metal) | - | ● | ● |
Johnson Matthey
| General information | |||
| Company: | Johnson Matthey | 
| |
| Country: | United Kingdom | ||
| Contact: | pharma@matthey.com | ||
| Webpage: | https://matthey.com/ | ||
| Technology and process details | |||
| Technology name: | Heterogeneous Catalyst | Technology category: | Conversion (Chemical processes and technologies) |
| TRL: | 9 | Capacity: | kg·h-1 |
| Catalyst: | Various options (Pd, Pt, Rh, Ru) | Temperature: | °C |
| Other: | |||
| Feedstock and product details | |||
| Feedstock: | Various (e.g. Acetylenes, Alkanes, Aromatics, Dienes, Esters, Furans, Indoles, Lactones, Olefins, Phenols, Quinolines) | Product: | Various |
As a global leader in sustainable technologies, we apply our cutting-edge science to create solutions with our customers that make a real difference to the world around us. We’ve been leaders in our field for more than 200 years, applying unrivalled scientific expertise to enable cleaner air, improved health and the more efficient use of our planet's natural resources. And now, as the world faces the challenges of climate change and resource scarcity, we have an even bigger role to play. Johnson Matthey will be central in accelerating the big transitions needed in transport, energy, chemicals production and creating a circular economy.
By applying the extensive guidance and research from our experts, we can customise catalysts for your specific needs giving you the best catalyst and process parameters for success. Johnson Matthey provides an essential service in terms of both catalysts supply and supporting optimal catalyst identification through in-house parallel screening experimentation and/or expert recommendations. Whether you're looking for an existing catalyst, customised solution, or to improve an existing process, our highly accessible support team is ready to work with you.
Topsøe Renewables
| General information | |||
| Company: | Topsøe Renewables | 
| |
| Country: | Denmark | ||
| Contact: | https://renewables.topsoe.com/contact | ||
| Webpage: | https://renewables.topsoe.com | ||
| Technology and process details | |||
| Technology name: | HydroFlex(TM) | Technology category: | Conversion (Chemical processes and technologies) |
| TRL: | 6-7 | Capacity: | kg·h-1 |
| Catalyst: | Various available (e.g. noble-metal, base-metal) | Temperature: | °C |
| Other: | |||
| Feedstock and product details | |||
| Feedstock: | Biogenic feedstocks such as virgin oils, waste oils and fats, or liquified solid waste | Product: | Drop-in fuels or naphtha |
Topsoe is a global supplier of catalysts, technology, and services to the chemical and refining industries, specialising in carbon reduction technologies. Topsoe Renewables is helping a number of major players in the refinery industry introduce full feedstock flexibility to their operations. Since 2004, Topsoe have been running dedicated research and development programs into renewable feedstocks for the refinery industry.
Working closely with their customers, Topsoe tailors HydroFlex™ to the layout of the plant, intended range of feedstocks, and the aied specifications of the renewable fuels. Renewable feedstocks, for example, all require dewaxing to optimise the cold flow properties of the resulting fuels.
Open access pilot and demo facility providers
Patents
Currently no patents have been identified.
References
- ↑ Yu-Chuan Lin, George W. Huber, 2009: The critical role of heterogeneous catalysis in lignocellulosic biomass conversion. Energy Environ. Sci., Vol. 2, (1), 68–80. doi: https://doi.org/10.1039/B814955K
- ↑ a b c d e Putla Sudarsanam, Ruyi Zhong, Sander Van den Bosch, Simona M. Coman, Vasile I. Parvulescu, Bert F. Sels, 2018: Functionalised heterogeneous catalysts for sustainable biomass valorisation. Chemical Society Reviews, Vol. 47, (22), 8349–8402. doi: https://doi.org/10.1039/C8CS00410B
- ↑ a b c Semakula Maroa, Freddie Inambao, 2021-10-22: A review of sustainable biodiesel production using biomass derived heterogeneous catalysts. Engineering in Life Sciences, Vol. , elsc.202100025. doi: https://doi.org/10.1002/elsc.202100025
- ↑ taken from Heterogeneous catalysis in wikipedia.