LAUSR

A novel strategy for comprehensive utilization of vanadium slag with high content chromium is proposed in present study. This approach involves two steps: vanadium slag is firstly treated by calcification roasting-sulfuric acid leaching method to extract vanadium. Then high carbon ferrochromium is smelted with the mixture by carbothermal reduction. In the 1st step, 99.41% vanadium in vanadium slag can be enriched in leaching liquor, however, the loss of chromium is negligible. The roasting and leaching parameters are studied. n(CaO)/n(V2O3)=0.5, 900oCand 60min are the optimum roasting conditions. 50oC, 60 min and sulfuric acid concentration 20% are the optimum leaching conditions. In the 2nd step, the chromium oxides and iron oxides are firstly reduced to chromium carbide and iron carbide, then further reduced to metallic chromium and iron with the increasing of temperature. The recoveries of chromium, iron and metal reach all exceed 95.00%. The chromium content in high carbon ferrochromium can achieve ov...