Abstract
The accumulation of significant amounts of metallurgical vanadium slags has a negative impact on the environment. It is relevant to maximize their involvement in industrial processing for the vanadium extraction. The article presents the results of hydrometallurgical vanadium extraction in the form of soluble vanadates from titanomagnetite ore processing slags (ITmk3 process slag and EVRAZ NTMK slag) using soda technology. The effect of leaching conditions (temperature and duration) on the vanadium extraction degree was investigated. Samples with a charge of slag and Na2CO3 were processed to oxidative roasting and subsequent water leaching at different temperatures from 50 °C to 80 °C for 1, 2 and 3 hours. The vanadium content in the solution was determined with X-ray fluorescence spectroscopy (XRF) and by titrimetric method. It was found that the slag chemical composition and the water leaching conditions had a significant effect on vanadium extraction degree. The vanadium extraction degree from the EVRAZ NTMK slag was 2–2,5 times higher than from the ITmk3 process slag under the same leaching conditions. The highest degree of vanadium extraction was obtained after leaching at a temperature of 80 °C for 3 hours. Application of the above leaching conditions increased the vanadium extraction degree from the EVRAZ NTMK slag to 65 – 87%, and from the ITmk3 process slag to 31 – 33%.
Keywords
Technogenic waste, vanadium slag, oxidizing roasting, leaching, vanadium extraction degree.