Synthesis of submicronic α-alumina from local aluminum slags

In this study, a high valued product submicronic α-alumina was successfully extracted from aluminum slags generated by the local aluminum industry. The extraction technique was based on the leaching of slags by H2SO4 followed by precipitation. The coarser aluminum-rich fractions of the slags were us...

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Main Authors: Benkhelif A., Kolli M., Hamidouche M.
Format: Article
Language:English
Published: University of Belgrade, Technical Faculty, Bor 2022-01-01
Series:Journal of Mining and Metallurgy. Section B: Metallurgy
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Online Access:http://www.doiserbia.nb.rs/img/doi/1450-5339/2022/1450-53392100053B.pdf
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author Benkhelif A.
Kolli M.
Hamidouche M.
author_facet Benkhelif A.
Kolli M.
Hamidouche M.
author_sort Benkhelif A.
collection DOAJ
description In this study, a high valued product submicronic α-alumina was successfully extracted from aluminum slags generated by the local aluminum industry. The extraction technique was based on the leaching of slags by H2SO4 followed by precipitation. The coarser aluminum-rich fractions of the slags were used in this study instead of the finer oxide-rich fractions that were commonly used in previous studies. The precipitation of the leached slags by NH4OH was controlled by a zetameter in order to determine the optimal precipitation pH. Then, the obtained gel showing the higher precipitation rate and the finer particle size was calcined at 1200 °C and characterized by the XRF, XRD, FTIR, SEM, EDS, and laser granulometry. Even without any pretreatment of slags, the XRF analysis revealed that a high purity and high extraction efficiency of 99.2% and 93.75% respectively could be achieved just at a leaching acid concentration of 15%. The XRD spectrum shows that the produced alumina was pure a-corundum, which was confirmed by the FTIR spectrum showing only the Al-O bonds. The laser granulometry showed that the recovered powder exhibited a wide particle size distribution, which was between 50 nm and 20 μm, while the average particle size (d50) was about 400 nm. The SEM observations revealed that the grains were in the form of submicronic whiskers. The above characteristics allowed the obtained alumina powder in this study to be used in the usual applications of alumina such as refractory, ceramic fibers, abrasive, etc. The obtained powders may also assume applications as a thermally stable substitute for the commonly used transition alumina powders, which needs further investigations in future studies.
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record_format Article
series Journal of Mining and Metallurgy. Section B: Metallurgy
spelling doaj-art-4514265a36134570adf3a65d69f39e5e2025-02-02T07:57:17ZengUniversity of Belgrade, Technical Faculty, BorJournal of Mining and Metallurgy. Section B: Metallurgy1450-53392217-71752022-01-0158111712710.2298/JMMB210401053B1450-53392100053BSynthesis of submicronic α-alumina from local aluminum slagsBenkhelif A.0Kolli M.1Hamidouche M.2Ferhat Abbas Setif University, Research Unit of Emergent Materials, Setif, Algeria + Ferhat Abbas Setif University, Institute of Optics and Precision Mechanics, Setif, AlgeriaFerhat Abbas Setif University, Research Unit of Emergent Materials, Setif, Algeria + Ferhat Abbas Setif University, Institute of Optics and Precision Mechanics, Setif, AlgeriaFerhat Abbas Setif University, Research Unit of Emergent Materials, Setif, Algeria + Ferhat Abbas Setif University, Institute of Optics and Precision Mechanics, Setif, Algeria + Research Center in Industrial Technologies CRTI, Cheraga, Algiers, AlgeriaIn this study, a high valued product submicronic α-alumina was successfully extracted from aluminum slags generated by the local aluminum industry. The extraction technique was based on the leaching of slags by H2SO4 followed by precipitation. The coarser aluminum-rich fractions of the slags were used in this study instead of the finer oxide-rich fractions that were commonly used in previous studies. The precipitation of the leached slags by NH4OH was controlled by a zetameter in order to determine the optimal precipitation pH. Then, the obtained gel showing the higher precipitation rate and the finer particle size was calcined at 1200 °C and characterized by the XRF, XRD, FTIR, SEM, EDS, and laser granulometry. Even without any pretreatment of slags, the XRF analysis revealed that a high purity and high extraction efficiency of 99.2% and 93.75% respectively could be achieved just at a leaching acid concentration of 15%. The XRD spectrum shows that the produced alumina was pure a-corundum, which was confirmed by the FTIR spectrum showing only the Al-O bonds. The laser granulometry showed that the recovered powder exhibited a wide particle size distribution, which was between 50 nm and 20 μm, while the average particle size (d50) was about 400 nm. The SEM observations revealed that the grains were in the form of submicronic whiskers. The above characteristics allowed the obtained alumina powder in this study to be used in the usual applications of alumina such as refractory, ceramic fibers, abrasive, etc. The obtained powders may also assume applications as a thermally stable substitute for the commonly used transition alumina powders, which needs further investigations in future studies.http://www.doiserbia.nb.rs/img/doi/1450-5339/2022/1450-53392100053B.pdfα-aluminaaluminum slagsacid leachingprecipitationcalcination
spellingShingle Benkhelif A.
Kolli M.
Hamidouche M.
Synthesis of submicronic α-alumina from local aluminum slags
Journal of Mining and Metallurgy. Section B: Metallurgy
α-alumina
aluminum slags
acid leaching
precipitation
calcination
title Synthesis of submicronic α-alumina from local aluminum slags
title_full Synthesis of submicronic α-alumina from local aluminum slags
title_fullStr Synthesis of submicronic α-alumina from local aluminum slags
title_full_unstemmed Synthesis of submicronic α-alumina from local aluminum slags
title_short Synthesis of submicronic α-alumina from local aluminum slags
title_sort synthesis of submicronic α alumina from local aluminum slags
topic α-alumina
aluminum slags
acid leaching
precipitation
calcination
url http://www.doiserbia.nb.rs/img/doi/1450-5339/2022/1450-53392100053B.pdf
work_keys_str_mv AT benkhelifa synthesisofsubmicronicaaluminafromlocalaluminumslags
AT kollim synthesisofsubmicronicaaluminafromlocalaluminumslags
AT hamidouchem synthesisofsubmicronicaaluminafromlocalaluminumslags