Biogenic Ashes Offer a Low-Carbon Future for Concrete

ETH Zurich researchers are developing cement substitutes from biogenic waste, such as crop residues and other organic by-products, by converting them into reactive ashes or biochar. These materials can partially replace Portland cement in concrete, significantly reducing CO₂ emissions associated with clinker production while potentially improving long-term carbon sequestration within the matrix. The team is investigating the chemical and microstructural mechanisms governing pozzolanic reactivity and durability, aiming to optimize formulations for scalable, low-carbon concrete. The research also highlights the need to integrate material performance with sustainable sourcing and circular-economy considerations to ensure real-world viability.