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Bauxite Enrichment by Microwave-Magnetising Roasting Using Sawdust as Reducing Agent

Received: 8 August 2014    Accepted: 22 August 2014    Published: 10 September 2014
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Abstract

As high grade bauxite is getting depleted in several parts of the world, bauxite with high iron content is becoming increasingly important, and this trend has called for studies into the reduction of iron in bauxite. This study investigated the use of microwave energy in the magnetising roasting of high-iron bauxite using sawdust as reducing agent. Mineralogical studies revealed gibbsite and goethite as the main constituents of bauxite. The sawdust utilised had a fixed carbon content of 7.2% and ash, 1.7%. Microwave heating responses of bauxite and sawdust were determined as a function of mass and time, and both materials proved to be active microwave absorbers as they heated rapidly. Magnetising roasting of the bauxite sample was conducted with 20-40% sawdust at temperatures between 870oC and 880oC. After magnetic separation, the major phase in the magnetic fraction was magnetite, while gibbsite and boehmite were the major phases in the non-magnetic fraction. The alumina content of the non-magnetic fraction increased to 87.5% from an as-received sample grade of 53.6%. The use of sawdust in this manner satisfies a dual role of environmental clean-up and bauxite enrichment.

Published in American Journal of Chemical Engineering (Volume 2, Issue 5)
DOI 10.11648/j.ajche.20140205.11
Page(s) 59-64
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

Bauxite, Sawdust, Microwaves, Magnetic Separation

References
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Cite This Article
  • APA Style

    Grace Ofori-Sarpong, Charles Ebenezer Abbey, Richmond Komla Asamoah, Richard Kwasi Amankwah. (2014). Bauxite Enrichment by Microwave-Magnetising Roasting Using Sawdust as Reducing Agent. American Journal of Chemical Engineering, 2(5), 59-64. https://doi.org/10.11648/j.ajche.20140205.11

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    ACS Style

    Grace Ofori-Sarpong; Charles Ebenezer Abbey; Richmond Komla Asamoah; Richard Kwasi Amankwah. Bauxite Enrichment by Microwave-Magnetising Roasting Using Sawdust as Reducing Agent. Am. J. Chem. Eng. 2014, 2(5), 59-64. doi: 10.11648/j.ajche.20140205.11

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    AMA Style

    Grace Ofori-Sarpong, Charles Ebenezer Abbey, Richmond Komla Asamoah, Richard Kwasi Amankwah. Bauxite Enrichment by Microwave-Magnetising Roasting Using Sawdust as Reducing Agent. Am J Chem Eng. 2014;2(5):59-64. doi: 10.11648/j.ajche.20140205.11

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  • @article{10.11648/j.ajche.20140205.11,
      author = {Grace Ofori-Sarpong and Charles Ebenezer Abbey and Richmond Komla Asamoah and Richard Kwasi Amankwah},
      title = {Bauxite Enrichment by Microwave-Magnetising Roasting Using Sawdust as Reducing Agent},
      journal = {American Journal of Chemical Engineering},
      volume = {2},
      number = {5},
      pages = {59-64},
      doi = {10.11648/j.ajche.20140205.11},
      url = {https://doi.org/10.11648/j.ajche.20140205.11},
      eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajche.20140205.11},
      abstract = {As high grade bauxite is getting depleted in several parts of the world, bauxite with high iron content is becoming increasingly important, and this trend has called for studies into the reduction of iron in bauxite. This study investigated the use of microwave energy in the magnetising roasting of high-iron bauxite using sawdust as reducing agent. Mineralogical studies revealed gibbsite and goethite as the main constituents of bauxite. The sawdust utilised had a fixed carbon content of 7.2% and ash, 1.7%. Microwave heating responses of bauxite and sawdust were determined as a function of mass and time, and both materials proved to be active microwave absorbers as they heated rapidly. Magnetising roasting of the bauxite sample was conducted with 20-40% sawdust at temperatures between 870oC and 880oC. After magnetic separation, the major phase in the magnetic fraction was magnetite, while gibbsite and boehmite were the major phases in the non-magnetic fraction. The alumina content of the non-magnetic fraction increased to 87.5% from an as-received sample grade of 53.6%. The use of sawdust in this manner satisfies a dual role of environmental clean-up and bauxite enrichment.},
     year = {2014}
    }
    

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  • TY  - JOUR
    T1  - Bauxite Enrichment by Microwave-Magnetising Roasting Using Sawdust as Reducing Agent
    AU  - Grace Ofori-Sarpong
    AU  - Charles Ebenezer Abbey
    AU  - Richmond Komla Asamoah
    AU  - Richard Kwasi Amankwah
    Y1  - 2014/09/10
    PY  - 2014
    N1  - https://doi.org/10.11648/j.ajche.20140205.11
    DO  - 10.11648/j.ajche.20140205.11
    T2  - American Journal of Chemical Engineering
    JF  - American Journal of Chemical Engineering
    JO  - American Journal of Chemical Engineering
    SP  - 59
    EP  - 64
    PB  - Science Publishing Group
    SN  - 2330-8613
    UR  - https://doi.org/10.11648/j.ajche.20140205.11
    AB  - As high grade bauxite is getting depleted in several parts of the world, bauxite with high iron content is becoming increasingly important, and this trend has called for studies into the reduction of iron in bauxite. This study investigated the use of microwave energy in the magnetising roasting of high-iron bauxite using sawdust as reducing agent. Mineralogical studies revealed gibbsite and goethite as the main constituents of bauxite. The sawdust utilised had a fixed carbon content of 7.2% and ash, 1.7%. Microwave heating responses of bauxite and sawdust were determined as a function of mass and time, and both materials proved to be active microwave absorbers as they heated rapidly. Magnetising roasting of the bauxite sample was conducted with 20-40% sawdust at temperatures between 870oC and 880oC. After magnetic separation, the major phase in the magnetic fraction was magnetite, while gibbsite and boehmite were the major phases in the non-magnetic fraction. The alumina content of the non-magnetic fraction increased to 87.5% from an as-received sample grade of 53.6%. The use of sawdust in this manner satisfies a dual role of environmental clean-up and bauxite enrichment.
    VL  - 2
    IS  - 5
    ER  - 

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Author Information
  • Mineral Engineering Department, University of Mines and Technology, Tarkwa, P. O. Box 237, Ghana

  • Mineral Engineering Department, University of Mines and Technology, Tarkwa, P. O. Box 237, Ghana

  • Mineral Engineering Department, University of Mines and Technology, Tarkwa, P. O. Box 237, Ghana ; Ian Wark Research Institute, The ARC Special Research Centre for Particle and Material Interfaces, University of South Australia, Mawson Lakes, Adelaide, SA 5095, Australia

  • Mineral Engineering Department, University of Mines and Technology, Tarkwa, P. O. Box 237, Ghana

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