Microwave-Assisted Carbothermal Reduction of Banded Hematite Jasper Ore

  • Veeranjaneyulu Rayapudi
  • Shrey Agrawal
  • Nikhil DhawanEmail author
Research Article


This study investigates the microwave carbothermal reduction of low-grade banded hematite jasper iron ore (Fe ~ 37%). The susceptibility of iron phases to microwave exposure and their selective absorptions help in the liberation of iron values from impurities. It was found that a small fraction of the microwave-irradiated ore-charcoal mixture was rapidly melted to produce pure ferrite balls with Fe ~ 90%. The ferrite balls were observed within 6-10 min of reduction at 8% and above charcoal at microwave power of 900 W. The iron grade deteriorated over prolonged exposure because of the formation of the fayalite phase. The optical micrograph of the ferrite ball reveals retained austenite and martensitic iron phases with an average hardness value ~ 302 HV and a saturation magnetization of ~ 190.4 emu/g.


Iron ore Microwave Carbothermal reduction Magnetic separation Ferrite 



The authors would like to thank and acknowledge the funding agency, the Science Engineering Research Board, for providing early career research funds via the grant no. ECR-000874/2016.

Compliance with Ethical Standards

Conflict of interest

On behalf of all authors, the corresponding author states that there are no conflicts of interest to disclose.


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Copyright information

© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  1. 1.Department of Metallurgical and Materials EngineeringIndian Institute of Technology, IIT-RoorkeeUttarakhandIndia

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