Extraction of vanadium from low-vanadium grade magnetite concentrate pellets with sodium salt

This study reported the extraction of vanadium from low-vanadium grade magnetite concentrate pellets using sodium salt. 71.1% of vanadium can be extracted under the following optimal conditions: pelletizing with 5 wt% Na2CO3, preheating at 1050 degrees C for 10 min, roasting at 1250 degrees C for 10 min, and water leaching at 120 degrees C for 120 min with a liquid:solid ratio of 5:1 (mL/g) in the bench-scale experiment. XPS and SEM-EDS results showed that part of trivalent vanadium was not oxidized completely during the sodium salt roasting and still occurred in the iron mineral phase; consequently, this part of vanadium was retained in the leached iron ore. The sodium salt roasting parameters are consistent with those of the iron ore oxidized pellets produced by grate-kiln or straight-grate methods; thus, the production efficiency of sodium salt roasting for vanadium extraction can be improved significantly. Pilot-scale experiment was further performed to verify the feasibility of the recommended method in a traveling grate, a better vanadium extraction ratio of 79.1% was achieved. (C) 2021 The Author(s). Published by Elsevier B.V.

Automated summary

This study focused on extracting vanadium from low-vanadium grade magnetite concentrate pellets using sodium salt, achieving a high extraction rate under optimal conditions. The research found that part of trivalent vanadium was not completely oxidized during the sodium salt roasting process. By optimizing the sodium salt roasting parameters, the production efficiency of vanadium extraction can be significantly improved.