More sustainable cements to reduce carbon dioxide emissions
(Year 2026)
Center for Design and Optimization of Processes and Materials (DIOPMA) UB | Molins
Cement production is responsible for approximately 7% of global CO₂ emissions, making the reduction of its carbon footprint one of the industry’s major environmental challenges.
In this context, the DIOPMA research group at the University of Barcelona and the Catalan cement manufacturer Molins are collaborating to develop a technology that partially reduces the use of clinker, the main component of Portland cement and one of the largest sources of emissions throughout the production process.
The first pilot trials of this innovative clay mechanical activation technology have demonstrated its feasibility, paving the way for the production of more sustainable cements while making use of locally available raw materials, in line with the sector’s sustainability goals.
This promising DIOPMA research line, accredited with the TECNIO label, originated at the end of 2020 as part of the PhD thesis of Dr Jofre Mañosa, co-supervised by Dr Josep Maria Chimenos, Professor at the Faculty of Chemistry of the University of Barcelona, and Dr Alex Maldonado, currently a researcher at the CETIM Technology Centre. The technology’s strong scientific and industrial potential led to the launch of a collaboration with Molins in 2024 to jointly explore this research and further validate the results in an applied industrial context.
The research aims to reuse clay-rich natural resources, whether naturally occurring or generated as by-products of industrial processes, as supplementary materials capable of partially replacing clinker in Portland cement. Until now, activating these clays—a necessary step to enable them to react properly within the cement matrix—has mainly relied on thermal processes that require fossil fuels and generate CO₂ emissions.
“What we propose is a mechanical activation process powered by electricity, which can come from renewable energy sources. As a result, the process itself generates lower carbon dioxide emissions, and the activated material has a significantly smaller carbon footprint,” explain Dr Mañosa and Dr Chimenos.
More raw materials, sourced locally
The technology’s truly distinctive feature is that this approach significantly broadens the range of raw materials that can be used. While thermal processes are limited to specific clay types, mechanical activation makes it possible to valorise other clay minerals that have so far remained outside the industrial production chain.
“This not only increases flexibility in the use of resources but also makes it easier to use locally available materials, reducing both environmental and logistical impacts,” the researchers add.
Preliminary carbon footprint analyses show substantial reductions compared with conventional cement production. In a scenario powered entirely by renewable electricity, mechanically activated clays can reduce CO₂ emissions by more than 60% compared with conventional thermal activation processes. This benefit is in addition to the emissions savings achieved by partially replacing clinker, the most carbon-intensive component of Portland cement.
Improving cement performance
Mechanical activation is not only a more sustainable solution but also a technologically competitive option for improving material performance. Depending on the processing conditions, researchers have observed improvements in several cement properties, including strength development and final microstructure.
“This is particularly significant because it allows clinker reduction to be seen not as a limitation but as an opportunity for technological improvement based on the use of abundant resources and process innovation, with real transformative potential for the construction materials industry,” they explain.
Towards industrial implementation
During the collaboration between both organisations, which is now entering its final stage, significant progress has been made in scaling up the technology. Building on laboratory results—in which two clay-rich resources with high potential as supplementary cementitious materials were identified—the researchers successfully took an important step towards process scale-up. Specifically, the technology was validated at pilot scale in collaboration with NETZSCH, a global leader in grinding equipment manufacturing.
“This stage has produced highly promising results from both technical and operational perspectives and further strengthens the feasibility of future industrial-scale implementation of the mechanical activation process in the near future,” the researchers emphasise.
The project also opens up collaboration opportunities beyond the cement sector. “The technology has considerable cross-sector potential and could foster new synergies while expanding the impact of these results to other industries interested in the valorisation of primary or secondary resources rich in clay materials,” they note.
From a knowledge transfer perspective, the researchers believe this project is an excellent example of how collaboration between universities and industry can create mutual value.
“On the one hand, industry contributes practical insight, a clear understanding of real sector needs and implementation capacity. On the other hand, academia provides specialised knowledge, innovation capability and a longer-term perspective. This combination has enabled faster and more robust progress towards viable solutions,” they conclude.
