TGA kinetic study on the hydrogen reduction of an iron nickel oxide

Content Provider	Semantic Scholar
Author	Yu, Dawei Zhu, Mingqian Utigard, Torstein A. Barati, Mansoor
Copyright Year	2013
Abstract	Abstract Reduction of a mixed iron nickel oxide by hydrogen to produce ferronickel alloy was investigated by thermo-gravimetric analysis (TGA). The iron nickel oxide, which contains 50 wt% Fe and 10 wt% Ni mainly in the form of hematite (Fe 2 O 3 ) and nickel ferrite (NiFe 2 O 4 ), is a residue produced from the water leaching of a selectively sulfation roasted nickel calcine. Continuous heating tests with a fixed heating rate as well as isothermal tests were performed. Results indicate that the reduction of the mixed oxide began above 350 °C. The reduction reactions occurred in a non-topochemical mode at low temperatures between 350 °C and 600 °C with its rate controlled by the solid–gas chemical reactions. The reduction rate increased with the increase in temperature from 350 °C up to 1100 °C. Between 600 °C and 1200 °C, the rate controlling step was the diffusion of reducing gas through the pores of the sample bed with an apparent activation energy of 34.1 kJ/mol. Due to the melting of the silicate material at 1200 °C which substantially reduced the sample porosity, the reduction rate decreased. Above 1200 °C, the reduction rate increased again due to the increased diffusion of the reducing gas through the molten sample at higher temperatures.
Starting Page	32
Ending Page	38
Page Count	7
File Format	PDF HTM / HTML
DOI	10.1016/j.mineng.2013.03.018
Volume Number	54
Alternate Webpage(s)	https://tspace.library.utoronto.ca/bitstream/1807/90630/1/TGA%20Kinetic%20study.pdf
Alternate Webpage(s)	https://doi.org/10.1016/j.mineng.2013.03.018
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article