Scalable Electrochemical Concrete Fabrication and Closed-Loop Recycling

Area of Science:

• Sustainable Materials Science
• Green Chemistry
• Circular Economy Engineering

Background:

• Concrete production is a major source of CO2 emissions and demolition waste.
• Current concrete recycling methods result in downcycling, limiting environmental benefits.
• A circular economy approach is needed to address concrete's unsustainability.

Purpose of the Study:

• To develop an electrochemical-driven recycling (ER) strategy for upcycling concrete waste.
• To regenerate high-value resources, including clinker precursors and pristine aggregates.
• To create carbon-neutral concrete with comparable performance to conventional concrete.

Main Methods:

• An electrochemical-driven recycling (ER) process was developed to decompose hydrated cement phases.
• Recovered materials were used to produce reversed Portland Cement and reversed concrete.
• The process was validated at a pilot scale (19.2 t/year).

Main Results:

• The ER strategy achieved 95.4 wt.% circularity.
• Global warming potential was reduced from 448.4 to -4.6 kg CO2-eq/m3, achieving carbon neutrality.
• Cost analysis showed competitiveness with conventional production, with potential net savings of up to $94.8/m3.

Conclusions:

• The ER strategy offers a scalable path toward circular concrete by closing material and carbon loops.
• This method transforms concrete demolition waste from an end-of-life problem into a valuable resource.
• Electrochemical recycling presents a viable and economical solution for sustainable concrete production.