2026-06-28T04:54:33Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/342892024-07-23T15:02:54Zcom_20.500.14352_14col_20.500.14352_15

Padilla, Isabel López Delgado, Aurora López De Andrés, María Sol Álvarez Aguirre, Marta Galindo Llorach, Roberto Vázquez Vaamonde, Alfonso J. 2023-06-19T13:42:09Z 2023-06-19T13:42:09Z 2014-01 2356-6140 10.1155/2014/82574 https://hdl.handle.net/20.500.14352/34289 https://www.hindawi.com/journals/tswj/2014/825745/ 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. eng https://creativecommons.org/licenses/by/3.0/es/ open access Atribución 3.0 España The Application of Thermal Solar Energy to High Temperature Processes: Case Study of the Synthesis of Alumina from Boehmite journal article