Effect of physicochemical properties and feed mix ratios on the carbothermic reductions of iron ore with coke

  • S.R.R. Munusamy (Faculty of Chemical Engineering & Technology (FKTK), Universiti Malaysia Perlis) ;
  • S. Manogaran (Faculty of Chemical Engineering & Technology (FKTK), Universiti Malaysia Perlis) ;
  • F. Abdullah (Faculty of Chemical Engineering & Technology (FKTK), Universiti Malaysia Perlis) ;
  • N.A.M. Ya'akob (Faculty of Chemical Engineering & Technology (FKTK), Universiti Malaysia Perlis) ;
  • K. Narayanan (Faculty of Chemical Engineering & Technology (FKTK), Universiti Malaysia Perlis)
  • Received : 2023.07.31
  • Accepted : 2024.01.05
  • Published : 2024.06.25


This study aimed to investigate the effect of physicochemical properties and mix ratios of iron ore (oxide feed): coke (reductant) on the carbothermic reductions of iron ore. Coke size was fixed at ≤63 ㎛ while iron ore size varied between 150-63 ㎛ and ≤63 ㎛ respectively. Mix ratios were changed from 100:0 (reference) to 80:20 and 60:40 while the temperature, heating rate and soaking duration in muffle furnace were fixed at 1100 ℃, 10 ℃/min and 1 hour. Particle size analyzer, XRF, CHNS and XRD analyses were used for determination of raw feed characteristics. The occurrence of phase transformations from various forms of iron oxides to iron during the carbothermal reductions were identified through XRD profiles and supported with weight loss (%). XRF analysis proved that iron ore is of high grade with 93.4% of Fe2O3 content. Other oxides present in minor amounts are 2% Al2O3 and 1.8% SiO2 with negligible amounts of other compounds such as MnO, K2O and CuO. Composite pellet with finer size iron particles (≤63 ㎛) and higher carbon content of 60:40 exhibited 45.13% weight lost compared to 32.30% and 3.88% respectively for 80:20 and 100:0 ratios. It is evident that reduction reactions can only occur with the presence of coke, the carbon supply. The small weight loss of 3.88% at 100:0 ratio occurs due to the removal of moisture and volatiles and oxidations of iron ore. Higher carbon supply at 60:40 leads into better heat and mass transfer and diffusivity during carbothermic reductions. Overall, finer particle size and higher carbon supply improves reactivity and gas-solid interactions resulting in increased reductions and phase transformations.



The authors would like to thank Universiti Malaysia Perlis (UNIMAP) and Faculty of Chemical Engineering & Technology (FKTK) for lab equipment and testing machines.


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