RT Journal Article T1 Semi-continuous flow mechanochemistry as a tool for the valorization of spent coffee grounds for biorefinery A1 Pérez-Merchán, Antonio Manuel A1 Cecilia-Buenestado, Juan Antonio A1 Mérida-Robles, Josefa María A1 Moreno-Tost, Ramón A1 Malpartida-García, Irene A1 Maireles-Torres, Pedro Jesús K1 Café - Industria K1 Mecanoquímica K1 Hidrólisis K1 Monosacáridos AB Spent coffee grounds (SCG) are a by-product of the coffee industry, with its production steadily increasing. In this study, a sequential biorefinery process for the valorization of SCG was investigated, aiming to produce biodiesel, 5-hydroxymethylfurfural (5-HMF) and activated carbon as products of significant industrial interest. In all these processes, conventional and mechanochemical-assisted methodologies were evaluated aiming at process intensification. Firstly, lipids were extracted from SCG and subsequently transformed into biodiesel using calcium diglyceroxide (CaDG) as heterogeneous catalyst, achieving a yield of 98.4 %. Afterwards, autohydrolysis of extracted SCG has allowed the recovery of hemicellulosic liquors, containing 22 % sugars in solution in the form of monomers (mainly C6) and oligomers. These sugar solutions were subjected to dehydration in a water, using CaCl2 and Al2O3, resulting in a maximum 5-HMF yield of 65 %. Finally, the residue obtained after these sequential processes, primarily composed of cellulose and lignin, underwent pyrolysis with KOH as an activating agent, producing activated carbon with a maximum surface area of 1359 m2/g. This cascade biorefinery approach demonstrates a sustainable pathway for SCG utilisation by minimizing waste and maximizing the production of valuable products. PB Elsevier SN 0956-053X YR 2025 FD 2025-06-15 LK https://hdl.handle.net/10630/38996 UL https://hdl.handle.net/10630/38996 LA eng NO Pérez-Merchán, A. M., Cecilia, J. A., Mérida-Robles, J. M., Moreno-Tost, R., Malpartida-García, I., & Maireles-Torres, P. (2025). Semi-continuous flow mechanochemistry as a tool for the valorization of spent coffee grounds for biorefinery. Waste Management, 204, 114946. NO Funding for open access charge: Universidad de Málaga / CBUA DS RIUMA. Repositorio Institucional de la Universidad de Málaga RD 19 ene 2026