Upcycling of construction and demolition waste: Recovery and reuse of binder and fine aggregate in cement applications to achieve circular economy

Abstract

The effective recycling and utilization of construction and demolition (C&D) waste to its maximum capacity to achieve a circular economy model is challenging in the current scenario. This current research emphasizes upcycling C&D waste using an acid dissolution method to separate the binder and aggregate fractions, and their performance was evaluated in cement mortar mixtures. The results showed that replacing 20% of cement with the recovered binder improved compressive strength by 8.07%, enhanced hydration product formation, and decreased water absorption and porosity by 11.48% and 5.21%, respectively. Replacing natural sand with recycled aggregates also resulted in comparable strength gains compared to reference mortars. The complete utilization of the secondary products from the upcycled C&D waste in construction activities helps to achieve sustainable development goals by reducing the carbon footprint and contributing to a circular economy model.

Keywords

• Construction and demolition waste
• Dehydroxylation
• Acid dissolution
• Cement chemistry
• Circular economy