We interviewed Dr Josep Maria Chimenos, Full Professor at the Faculty of Chemistry of the University of Barcelona, about an innovative project he leads within the DIOPMA research group, focused on developing more sustainable cement with a lower carbon footprint.

The project has been selected in the Proof of Concept (PoC) call of the Innovation Promotion Fund (F2I), an initiative of the University of Barcelona aimed at boosting innovation and knowledge transfer activities among its researchers.

Your project is ambitious: you aim to develop more sustainable cement with a lower carbon footprint.

Exactly. We are working to reuse clays from secondary or low-grade resources, whether natural or industrial, that currently cannot be valorised. For these secondary clay resources to partially replace Portland cement, they must be activated so that they acquire reactivity and can generate phases similar to those of conventional cement, while maintaining its properties.

Traditionally, this activation is carried out through thermal processes that consume fossil fuels and generate CO₂ emissions. Our proposal is to replace them with mechanical activation, based on the use of renewable energy, which almost completely eliminates these emissions. In this way, we achieve a double benefit: we reuse secondary resources and produce more sustainable cement.

What are “secondary clay resources” and where do they come from?

Clays are materials rich in aluminosilicates and are very abundant in the Earth’s crust, and they are widely used in sectors such as ceramics and construction. However, not all clays are suitable for industrial use. So-called secondary resources are materials that, due to their composition or quality, cannot be commercialised. Our goal is to reuse these materials and make them suitable to partially replace Portland cement.

What makes your project innovative compared to existing solutions?

The main innovative element is the activation method. Traditionally, clay materials are activated through thermal processes that require fossil fuels and generate CO₂ emissions. Our proposal is based on mechanical activation using electrical energy, which makes it possible to incorporate renewable sources and significantly reduce emissions. In addition, we have demonstrated at laboratory scale that this process broadens the range of clay minerals that can be activated, further increasing the potential applications of the technology.

The DIOPMA group has a clear focus on sustainable materials research. How does this project fit into that line?

Our research focuses on developing construction materials with the lowest possible carbon footprint. In this case, we are working to reintroduce into the production cycle secondary resources that were previously unused and often ended up in landfills, as well as natural resources that could not be used due to their composition.

What does it mean for your project to have been selected in the F2I call?

It allows us to scale up the results obtained so far. We are currently working at laboratory scale, but the F2I funding will enable us to take a qualitative step forward and develop a proof of concept at a much larger scale. The goal is to demonstrate that we can also activate these secondary clay resources when working with hundreds of kilograms of material and obtain a binding material with properties similar to Portland cement.

How could this project impact the construction sector?

Several industrial sectors are interested in this technology. On the one hand, the cement industry, which is seeking more sustainable alternatives. On the other hand, sectors such as mining or quarrying, as well as companies that could develop the technology needed to scale the process, such as mill manufacturers. Moreover, it is a solution with global potential, as clays are abundant worldwide. It may also have applications in industries that generate clay-rich waste, such as drinking water treatment plants.

More about… Josep Maria Chimenos

The best invention in history?

Materials have been decisive in the progress of humanity, to the point of defining historical periods such as the Stone Age or the Iron Age. Each new material has driven profound changes in the way we live and produce. However, on a personal level, I would highlight penicillin for its dramatic impact on reducing mortality and for initiating a revolution in healthcare systems.

What would you like to see in the future?

I would like to see a world at peace, although in the current context it may seem like a utopia. Also, a fairer society in which inequalities such as hunger, lack of opportunities or discrimination have been overcome, and where well-being is more accessible.

A future advancement that concerns you?

It is not technological advances themselves that should concern us, but how we use them. Throughout history, all technologies have had a dual potential, with both positive and negative applications. They may raise concerns, such as job losses or impacts on critical thinking. However, they also have the potential to drive major advances in areas such as health, energy or scientific research.

A role model?

Figures such as Isaac Newton, Albert Einstein or Stephen Hawking have profoundly shaped knowledge. In the field of sustainable cement, I would highlight researchers who have driven the development and application of these materials, including Víctor Glukhovsky, Ángel Palomo, Karen Scrivener, Fernando Martirena, Barbara Lothenbach and John Provis.

What could be done to achieve gender equality?

We need to stop valuing people based on their gender and instead do so based on their abilities and contributions. True equality will come when gender no longer determines opportunities or recognition.

Knowledge transfer is important for…

Ensuring that all the knowledge and innovations we generate reach society. Through knowledge transfer, it is possible to scale what we have developed in the laboratory and move towards small-scale validation phases, proof-of-concept studies, industrial pilots and, ultimately, real-world implementation. Without this bridge between research and the productive sector, knowledge would remain confined to laboratories and would not translate into tangible improvements for society.