Metall. Res. Technol.
Volume 115, Number 6, 2018
|Number of page(s)||7|
|Published online||11 December 2018|
Sequential extraction of vanadium and chromium from chromium-bearing vanadium slag through two-stage soda roasting-water leaching
College of Materials Science and Engineering, Chongqing University, Chongqing
400044, PR China
Accepted: 30 August 2018
The sequential extraction of vanadium and chromium from the chromium-bearing vanadium slag through two-stage soda roasting-water leaching was proposed. The precipitation order and thermodynamic stability of Cr-spinel and V-spinel were thoroughly calculated with FactSage 6.3 software. The mechanism of the sequential extraction process is further determined by X-ray diffraction (XRD). Thermodynamic calculations show that the precipitation order of main phases in the chromium-bearing vanadium slag is as follows: Cr-spinel → V-spinel → Fe-olivine, while the priority of the reaction between main phases with Na2CO3 follows the order of Fe-olivine → V-spinel → Cr-spinel. XRD results reveal that the vanadium-bearing phase in roasted slag is water-soluble NaVO3, while the chromium-bearing phase in roasted slag is Cr-spinel ((Mn, Fe) Cr2O4) and solid solutions ((Fe0.6Cr0.4)2 O3) with the soda amount of 21% and temperature of 800 °C. The different evolution route of vanadium-bearing phase and chromium-bearing phase during the roasting process ensures preferential extraction of vanadium from the chromium-bearing vanadium slag. The leaching rates of vanadium and chromium reach 89.36% and 4.91% with optimized experimental conditions. The high leaching rate of vanadium and low leaching rate of chromium show good results of preferential extraction of vanadium from the chromium-bearing vanadium slag.
Key words: sequential extraction / chromium-bearing / vanadium slag / V-spinel / Cr-spinel
© EDP Sciences, 2018
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.