Mining and industrial waste: A mechanochemical approach to CO2 mitigation

The ongoing growth of atmospheric CO2, related to human industrial activities, has now reached a concentration of 420 ppm (Calvin et al., 2023; Lu et al., 2025). As it is well known, the increased carbon dioxide concentration is also related to global warming (Calvin et al., 2023). In this context, scientists, researchers, and scholars worldwide are studying to achieve the objective of the Paris Agreement towards climate neutrality. Among the several techniques studied by the scientific community, CCUS (Carbon Capture Utilisation and Storage) technologies are gaining increasing appeal (Tapia et al., 2018; Zhang et al., 2020; Dziejarski et al., 2023). In particular, the carbon mineralization reaction, inspired by the natural weathering of minerals, is among the wide array of CCUS approaches (Seifritz, 1990; Cau et al., 2024; Weiler et al., 2024). In this context, the present study investigates the possibility of using granite scraps and red muds to mitigate the greenhouse effect, through the mineralization of atmospheric CO2. The aim of this research is to mimic the natural reactions between rock, carbon dioxide, and water, and to enhance the reaction kinetics using mechanochemical approaches. What was observed is that, under specific conditions, the systems were able to absorb 80% of the CO2 fluxed in the reactor, also producing 10% (v/v) of hydrogen and over 350ppm of methane. Furthermore, a focus is placed on the reaction mechanisms and the conditions that affect the final process yield.