KnE Materials Science
ISSN: 2519-1438
The latest conference proceedings on physical materials, energy materials, electrical materials.
Hydrothermal Resource-saving Processes in Complex Processing of Bauxite and Red Mud
Published date: Dec 31 2020
Journal Title: KnE Materials Science
Issue title: IV Congress “Fundamental Research and Applied Developing of Recycling and Utilization Processes of Technogenic Formations” Volume 2020
Pages: 383–390
Authors:
Abstract:
The Bayer bauxite residue (red mud, RM) is environmentally hostile and hazardous to human health. Red mud can be viewed as an important and promising source of scandium, yttrium, zirconium and other elements rather than a solid waste. Due to a high content of iron in bauxites and especially in RM, the conversion of hematite into magnetite in Bayer liquor plays a key role in the exploration of a cleaner technology of alumina production. Thus, RM and raw bauxite were used for hydrothermal digestion in an original one-stage method of magnetite production during co-recovery of alumina. The yield of alumina reaches 80% from RM and more from bauxites during digestion with addition of lime and Fe(II) or Fe . The saturation magnetization of a bulk sample of magnetized bauxite is 40.5 emu/g, two orders of magnitude higher than that of a raw red mud sample. Moreover, magnetite containing a residue has a high crystallinity, which contributes to better deposition and magnetic separation in the development of an overall flowsheet for RM utilization.
Keywords: Red mud, bauxite, hydrothermal treatment; enrichment, extraction, magnetization, hematite, magnetite, rare elements
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