Zeolites: the cornerstone of the petrochemical industry... and our future

Zeolites are microporous materials widely used in chemical processes. They present many applications, from agriculture - they can help improve soil permeability or retain water and nutrients - to environmental control or biomedicine.

These structures have been key materials for the petrochemical industry since their application as improved catalysts in cracking reactions in the 60s, substituting the previous amorphous silica-alumina catalysts, permitted a substantial increase of fuel production, fact that resulted in a more sustainable fossil fuel consumption.

Furthermore, more and more frequently, zeolites and ordered porous materials are finding new applications in other fields of the chemical industry, such as the production of high-value-added compounds, in particular synthetic fragrances, food additives or new pharmaceutical formulations, as well as synthetic fuels. Zeolites are, therefore, vital for obtaining clean fuels and moving towards an increasingly sustainable society closer to decarbonisation.

But how do they work, what are the keys to these microporous materials, and what are their challenges? The answer to these questions lies with Avelino Corma, one of the world's leading chemists and a researcher at the Universitat Politècnica de València -Institute of Chemical Technology (UPV-CSIC), which he founded in 1990.

The key to zeolites lies in their structure, characterised by a succession of tiny regular pores that allow the entry of molecules into their interior; their catalytic properties enable these molecules to be selectively transformed into the products of interest thanks to the control of the size of their pores and cavities. Thus, depending on the chemical composition and topology of these structural pores, it is possible to develop different chemical reactions for other applications.

As Professor Corma explains, the structure acts like a sieve, letting through only molecules smaller than the pores. This is why zeolites are commonly used in many catalytic processes and significantly impact industries such as petrochemicals, fine chemicals, and gas separation.

But what happens when zeolites interact with large molecules such as those found in heavy oils and fuels? To solve this problem, Professor Corma's team has developed zeolite synthesis processes using acids and high temperatures to achieve larger mesopores, thus obtaining zeolites that can react with larger molecules.

In the current context, in which decarbonisation is a necessity to improve the sustainability of our society, the design of zeolitic materials focuses its challenges on reducing atmospheric emissions of greenhouse gases, mainly in the capture of CO2 and its transformation into products of interest, the production of hydrogen or obtaining high value-added products from renewable sources, such as biomass.