Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
212430 | Hydrometallurgy | 2013 | 7 Pages |
This preliminary study examined the role of microwave radiation on precipitation and aging of iron oxyhydroxides at 60 °C. It was observed that due to rapid heating under microwave, transformation of two line ferrihydrite to α-Fe2O3 takes place within 4–10 h. This is in contrast to the usual aging temperature of > 100 °C adopted in most conventional studies, and several days of aging. Besides rapid transformation, microwave helps forming nanoparticles, with crystallite size of ~ 60 nm as determined from X-ray diffractograms, and < 100 nm particles as observed under TEM. Rapid transformation also promotes formation of α-Fe2O3 without the formation of intermediate γ-Fe2O3. This study brought out the advantages of low temperature microwave assisted precipitation/aging as a low energy process to transform iron oxyhydroxides, with likely applications in slurry rheology, synthesis of nanoparticles, and adsorption.
► Precipitation of iron hydroxide under ambient condition ► Aging of the precipitate under microwave at 60 °C ► Characterisation of the precipitate through XRD, TG, TEM, and BET ► The α-Fe2O3 formed after aging was of nanosize. ► A low temperature method to prepare fine iron oxide particles