Carbothermal Upgrading of the Awaso Bauxite Ore using Sawdust and Coconut Shells as Reductant

  • Allen Yushark Fosu University of Mines and Technology
  • Nelson Fosu University of Mines and Technology
  • Kwaku Owusu Boateng University of Mines and Technology
  • James Ransford Dankwah University of Mines and Technology
Keywords: Bauxite, Palm nut shells, Gas-fired furnace, Hercynite, Char.

Abstract

Ghana’s bauxite is exported in the raw state with no value addition. One way to achieve value addition is to carbothermally upgrade the ore into magnetic and nonmagnetic fractions, followed by separation using a magnet. This work investigates the carbothermal upgrading of the Awaso bauxite ore using reductant generated from locally available saw dust (SD) and coconut shells (CNS). Composite pellets of bauxite-reductant were prepared, air-dried and cured for 72 hours. The cured pellets were placed in a fire-clay crucible and heated in a custom-made gas-fired furnace for 30 minutes. The fired composite pellets were separated into magnetic and non-magnetic portions using a low intensity hand-held magnet. The various portions were then characterised using XRD, XRF and SEM analyses. XRD results showed magnetite as the predominant species present in the magnetic fraction whilst the non-magnetic fraction showed alumina as the predominant peaks along with some traces of unreduced hematite, silica, carbon and titania but no hercynite.

Author Biographies

Allen Yushark Fosu, University of Mines and Technology

Student, Minerals Engineering Department

 

Nelson Fosu, University of Mines and Technology
Minerals Engineering Department
Kwaku Owusu Boateng, University of Mines and Technology
Minerals Engineering Department
James Ransford Dankwah, University of Mines and Technology
Senior Lecturer, Minerals Engineering Department

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Published
2016-12-20