Researchers at Stanford University have developed a low-carbon cement formulation based on volcanic rock that could significantly reduce emissions from cement production.
The material, known as “Phlego”, replaces limestone with carbonate-free igneous rock, which does not release CO2 when heated in the kiln. In conventional cement production, the calcination of limestone accounts for nearly two-thirds of total emissions, making it a key target for decarbonisation efforts.
By substituting limestone with volcanic-derived material that has already undergone natural thermal processes, the new formulation can reduce emissions by up to two-thirds while maintaining comparable performance to traditional cement.
The technology also addresses growing constraints in the supply of supplementary cementitious materials (SCMs), such as fly ash, which are increasingly limited as coal-fired power generation declines. Engineered pozzolans such as Phlego could provide a more consistent and scalable alternative.
Developed by a team led by Stanford researcher Tiziana Vanorio, the material is designed to be compatible with existing cement production infrastructure, reducing barriers to industrial adoption. The project has progressed from laboratory validation to early-stage commercial development with support from the Stanford Sustainability Accelerator, including the acquisition of pilot-scale equipment and engagement with industry stakeholders.
The researchers are now working to scale up the process and bring the technology to market.
