Secondary raw materials are key in the circular economy. The concept itself is at the intersection of two circular principles: eliminating waste (by diverting waste flows to recycling and recovery plants) and maintaining the value of components. Secondary raw materials also contribute to strategic autonomy and resilience by reducing reliance on virgin raw materials which are not available domestically.

The ECESP website has plenty of examples of secondary raw materials. This series will shine a spotlight on some of them!

Secondary raw material concept: construction materials from industrial CO₂ emissions and citrus peels

The BUILD-LIMONENE initiative is developing sustainable and efficient materials for the construction industry obtained from carbon dioxide generated by industries in the Valencian Community and waste produced by the citrus sector.

Specifically, it is endeavouring to develop additives and biodegradable materials with a lower carbon footprint that can be used in the construction industry and become viable alternatives to the fossil-based materials currently available.

This new technology will contribute to the recovery of waste by using citrus peels and CO₂ emissions.

Results

Currently, most additives and coatings for construction materials are obtained from virgin fossil materials. This project is studying the processes involved in producing polycarbonates and polyurethanes based on or synthesised from CO₂ to open up a new field of innovation that promotes the development of construction materials with fewer harmful effects.

The project is currently in the experimentation stage. The catalytic reaction of limonene oxide and CO₂ is being optimised to obtain polycarbonates with specific characteristics. Limonene is a natural chemical substance that can be extracted from citrus peels and is a fundamental ingredient in these formulations.