Transformation of Magnetite ( Fe 3 O 4 ) and Maghemite ( γ – Fe 2 O 3 ) to a – Fe 2 O 3 from Magnetic Phase of Glagah Iron Sand

Content Provider	Semantic Scholar
Author	Wahyuningsih, Sayekti Ramelan, Ari Handono Kristiawan, Yosep Rio
Copyright Year	2019
Abstract	The study of magnetite (Fe3O4) and maghemite (γ-Fe2O3) transformation to α-Fe2O3 from magnetic phase of Glagah iron sand has been done. Glagah sand was magnetised to separate magnetic and non-magnetic sand. Then, it was prepared by ball milling for 5 h (20:1 w/w) to reduce the particle size. Magnetic iron sand was roasted at 1,000°C with the addition of sodium carbonate (Na2CO3) (sand mass ratio: Na2CO3 1:2 w/w) for 2 h to reduce the silicon dioxide (SiO2) content. Characterisation of X-ray fluorescence after magnetic separation, ball milling and roasting showed an increasing percentage of Fe2O3 from 31.10% to 70.13%. Furthermore, magnetic iron sand was refluxed using hydrochloric acid (HCl) with concentrations of 3, 6, 9 and 12 M for 2 h. Then, the aqueous phase was precipitated with the addition of 3 M ammonium hydroxide (NH4OH). The obtainable sediments showed Fe2O3 optimal percentage at concentration of 12 M by 67.96%. Calcination of Fe2O3 at 400°C, 600°C and 800°C showed a phase transformation of Fe3O4 and γ-Fe2O3 to α-Fe2O3 which reached an optimum was 92.23% at a temperature calcination of 800°C was showed an optimum percentage (92.23%) of phase transformation of Fe3O4 and γ-Fe2O3 to α-Fe2O3 at a temperature of 800°C. While the thermogravimetry/different thermal analysis showed the formation of a stable α-Fe2O3 after a temperature at 707.9°C is indicated by no longer mass loss.
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Alternate Webpage(s)	http://web.usm.my/jes/15_2019/JES_15_2019_2.pdf
Language	English
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Content Type	Text
Resource Type	Article