Abstract
The influence of magnesium on roasting vanadium slag was investigated by simulating the roasting process of vanadium by mixing V2O5 and MgO. The calcination products of V2O5 reacted with MgO at different temperatures which were characterized by X-ray diffraction (XRD), Thermogravimetry-differential scanning calorimetry (TG-DSC) and scanning electron microscope (SEM). There were two mass loss intervals, three endothermic peaks and one exothermic peak appearing during the reaction by the integrated thermal analysis as the temperature increased from room temperature to 1273.15 K. The samples of mixed V2O5 and MgO began to melt at 573.15 K and reacted at 773 K, and the shape of the particles changed from block to ovoid or irregular sphere at 773.15 K. With increasing the reaction temperature from 973.15 to 1073.15 K, the intermediate of VO2 was produced, and MgV2O6 was partially decomposed at 1073.15 K. During this process, the particle shape gradually returned to block shape. The conversion rate of vanadium is 99.4% with MgO of 1.65%.
Highlights
Up to now, about 88% reserves of vanadium in the world are extracted from vanadium-titanium magnetite (Qiu et al 2011), and the rest of that is collected from various minerals such as stone coal, and spent catalyst (Moskalyk & Alfantazi 2003, Li et al 2013).Vanadium slag is a crucial raw material for preparing vanadium and steel material containing vanadium in the present research
For the traditional vanadium production process, the vanadium slag is used to be roasted with sodium salt or calcium salt (Voglauer et al 2004, Gabra & Malinsky 1981, Bradbury 2002, Song et al 2014, Li et al 2015, Cao 2012, Chen et al 2013), such as NaCl, Na2CO3, or Na2SO4 in rotary kiln or multiple hearth furnace filled with oxidizing atmosphere at the temperature around 1023.15 to 1123.15 K
The differential thermal analysis (DTA) figure 4b shows that the endothermic peak near the temperature of 443.15 K was due to the dehydration reaction, and the exothermic peak appears around the temperature of 743.15 K was due to the formation of MgV2O6 and crystal transformation of V2O5
Summary
About 88% reserves of vanadium in the world are extracted from vanadium-titanium magnetite (Qiu et al 2011), and the rest of that is collected from various minerals such as stone coal, and spent catalyst (Moskalyk & Alfantazi 2003, Li et al 2013). For the traditional vanadium production process, the vanadium slag is used to be roasted with sodium salt or calcium salt (Voglauer et al 2004, Gabra & Malinsky 1981, Bradbury 2002, Song et al 2014, Li et al 2015, Cao 2012, Chen et al 2013), such as NaCl, Na2CO3, or Na2SO4 in rotary kiln or multiple hearth furnace filled with oxidizing atmosphere at the temperature around 1023.15 to 1123.15 K. Magnesium exists in vanadium slag in the form of spinel and complex oxides containing various metals (Wang 2011). There are few researches about effects of magnesium except chromium (Liu et al 2016) and calcium (every 1% increase in CaO in slag will lose 4.7%–9.0% of V2O5 (Peng et al 2007)). The effect of the roasting temperature on vanadium extraction and the characterization of leach residues are discussed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
