The key role of catalysts

There are many different ways to approach this issue, and efforts from all sides are needed to solve the problem. However, among all of the possible options to reduce and manage CO₂ emissions, it is important to remember what the most recognised experts in chemistry advised many years ago.

The concept of the ‘Green Carbon Science’ and its importance was introduced by Prof. Dr Avelino Corma and Prof. Dr Mingyuan. They established a new future scenario where required chemicals could be produced based on the hydrogen from water, and renewable energy and carbon from biomass and CO₂.^2,3

The Nobel Laureate Prof. Dr George A. Olah published his book ‘Beyond Oil and Gas: The Methanol Economy’ in 1994, where he advanced that the solution to replace fossil fuels would come through CO₂ conversion to methanol and other chemicals by reaction with green hydrogen.⁴

This article will corroborate again how catalysts play a crucial role in the energy transition, specifically in the conversion of CO₂ to chemicals and fuels, and will review the current status of some major industrial projects.

The electrification of cars is one important element of the energy transition, but there are some considerations to be made. On one side, the renewal of the car park and the gas station network is very expensive. Batteries also have a high cost, heavy weight, and short life, as well as short autonomy and long charging times. On the other side, electrification cannot be applied to aviation or heavy vehicles or ships. For all these reasons, technologies that are based on a circular economy of carbon are becoming more relevant. In this way, keeping the same infrastructure and engines, and combining them with the use of biofuels, would make reaching the carbon neutrality goals set for 2050 more possible.

The CO₂ molecule is extremely stable due to the two double bonds carbon to oxygen. This high stability means that the energy needed to convert this chemical to other substances is extremely high. Consequently, the role of catalysts is more important than ever, because they are required to lower the activation energy to obtain the desired reactions. The CO₂ molecule is also extremely versatile. Thanks to catalytic reactions, 17 different chemical compounds can be obtained from CO₂: methanol, ethanol, ethylene, acetaldehyde, dimethyl ether, methane, carbon monoxide, acetone, acetate, formate, alkylalcohol, 1-propanol, glycolaldehyde, propionaldehyde, ethylenglycol, hydroxyacetone and glyoxal.⁵

It is well known that CO₂ is a chemical already widely used in the industry, including several industrial processes that use CO₂ as a raw material to convert it into value-added chemicals. Currently, the annual volume of CO₂ used by the industry is approximately 120 million t, which is less than 0.5% of the total annual anthropogenic emissions of CO₂ (34 billion t).⁶ For this reason, the search for CO₂ applications where this chemical is a precursor for chemical processes is a very urgent task.

Written by Dr Meritxell Vila, MERYT Catalysts & Innovation, Spain.

This article was originally published in the November 2021 issue of Hydrocarbon Engineering magazine. To read the full article, sign in here or register for a free trial subscription.

References

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Read the article online at: https://www.hydrocarbonengineering.com/special-reports/04112021/the-key-role-of-catalysts/