RT Journal Article T1 The Application of Thermal Solar Energy to High Temperature Processes: Case Study of the Synthesis of Alumina from Boehmite A1 Padilla, Isabel A1 López Delgado, Aurora A1 López De Andrés, María Sol A1 Álvarez Aguirre, Marta A1 Galindo Llorach, Roberto A1 Vázquez Vaamonde, Alfonso J. AB The aim of this paper is to evaluate the feasibility of obtaining alumina from boehmite using a free, clean, and unlimited power source as the solar energy. Boehmite was obtained by hydrothermal treatment of a hazardous waste coming from aluminum slag milling. The waste is considered as a hazardous substance because of it releasing toxic gases (hydrogen, ammonia, methane, and hydrogen sulfide) in the presence of water. The as-obtained boehmite was transformed into alumina, in air atmosphere, using a solar energy concentrator (Fresnel lens). The solar installation provides a power density of 260 W·cm−2 which allows reaching temperatures upper than 1000°C at few minutes of exposure. Tests were performed at different periods of time that ranged between 5 and 90 min. The percentage of transformation of boehmite into alumina was followed by the water content of samples after solar radiation exposure. Samples were characterized by X-ray diffraction, infrared spectroscopy, and thermogravimetry. Metastable aluminas started to appear at 5 min and the crystalline and stable phase corundum at 10 min of solar radiation exposure. PB Hindawi Publishing Corporation SN 2356-6140 YR 2014 FD 2014-01 LK https://hdl.handle.net/20.500.14352/34289 UL https://hdl.handle.net/20.500.14352/34289 LA eng NO Universidad Complutense de Madrid NO Consejo Superior de Investigaciones Científicas (CSIC) DS Docta Complutense RD 13 abr 2025