A team of engineers from the University of São Paulo and Princeton University has developed a new method to recycle cement waste into a sustainable, low-carbon alternative.

The material, which performs comparably to traditional Portland cement, could significantly reduce the environmental impact of concrete. In their study, which was published in ACS Sustainable Chemistry & Engineering, the researchers demonstrated that mixtures containing up to 80% recycled cement achieved strength levels on par with conventional Portland cement. Crucially, this recycled alternative generates only a fraction of the carbon emissions associated with Portland cement, which is widely used as the primary binder in concrete production. Portland cement's high carbon intenstity is a major contributor to the cement and concrete industry’s 8% share of global CO2 emissions. By offering a viable recycled substitute, this new approach addresses a critical challenge for the sector. 

The researchers estimate that, if used alongside other emerging technologies designed to replace cement, this innovation could cut emissions from the cement industry by up to 61%.