Valorization of Marble Wastes through Innovative Green Technologies for a Circular Economy Future

The marble industry, a key sector of Italy’s industrial and cultural heritage, plays a relevant economic role in the modern society. Anyway, marble extraction and processing, with particular attention to cutting, polishing and finishing operations, generate large volumes of solid and liquid wastes. These industrial by-products remain largely underutilized. Therefore, it is pivotal to find new sustainable and economically viable valorization strategies in agreement with the circular economy principles. In this context, the regional project “Marble-Up – Recovery and Valorization of Marble Sludge” aims to develop innovative solutions for the reuse and valorization of marble wastes. The project is structured in two main research sections: (1) the characterization and potential reuse of solid residues and (2) the eco-friendly treatment of liquid effluents. Within the first goal, powders and sludges from sawing and polishing have been characterized by FT-IR spectroscopy, BET surface area analysis and water/linseed oil absorption tests to evaluate their chemical composition, porosity and surface properties. The second goal focuses on the removal of fine marble particles and residual additives from the liquid effluents, in order to replace conventional flocculants, such as polyacrylamide and metal salts, with safer, bio-based alternatives, including chitosan, polyglutamic acid, starch, sodium alginate, together with their chemically-modified derivatives. Overall, this research contributes to an efficient transition toward sustainable materials management in the marble industry.