In a groundbreaking review published in the journal “Case Studies in Construction Materials,” researchers have outlined a promising shift in the cement and concrete industry’s approach to carbon dioxide (CO₂) emissions. The study, led by Sanghwan Cho of the Department of Civil Engineering at Seoul National University of Science and Technology, explores innovative methods to transform CO₂ from an environmental burden into a valuable component of construction materials.
The cement and concrete industry is a significant contributor to global CO₂ emissions, accounting for nearly 8%. Traditional mitigation strategies have primarily focused on reducing emissions, but this review highlights a paradigm shift: utilizing CO₂ as a functional material component. “This is not just about reducing emissions; it’s about reimagining CO₂ as a resource,” Cho explains.
The research evaluates three key areas: carbonation curing, CO₂-reactive aggregates, and alternative binders. Carbonation curing, a process that involves exposing concrete to CO₂, has shown remarkable benefits. It accelerates hydration kinetics, enhances early-age strength, and refines pore structures while permanently sequestering CO₂. “The results are promising,” Cho notes. “We’re seeing improved mechanical properties and durability, which could have significant commercial implications.”
CO₂-modified aggregates, such as carbonated recycled concrete aggregates (RCA) and steel slag, offer another avenue for CO₂ utilization. These materials not only reduce waste but also improve mechanical integrity, potentially lowering production costs and enhancing product performance.
Emerging binders, including alkali-activated and magnesium-based cements, enable in-situ CO₂ mineralization. These alternatives to traditional Portland cement could significantly reduce the carbon footprint of the construction industry. “The potential is enormous,” Cho says. “We’re talking about a viable low-carbon alternative that could revolutionize the industry.”
However, the path to large-scale implementation is not without challenges. High CO₂ capture costs, suboptimal carbonation kinetics, and the absence of regulatory frameworks hinder widespread adoption. The review highlights these barriers and suggests future research directions, including machine learning-driven mix optimization, automated carbonation control, and integrated life-cycle assessment.
The study lays the foundation for next-generation carbon-neutral cementitious materials, advancing both sustainability and high-performance construction. As the energy sector seeks innovative solutions to reduce emissions, this research offers a compelling glimpse into the future of the cement and concrete industry. By shifting CO₂ from an environmental burden to a value-added resource, the study paves the way for a more sustainable and economically viable construction sector.