钒铬渣钠化焙烧同步提取钒和铬

Simultaneous Extraction of Vanadium and Chromium from Vanadium-chromium Slag by Sodium Roasting

通过钒铬渣钠化焙烧化学反应理论分析和热力学计算,提出采用高碱低温钠化焙烧同步提取钒和铬。主要考察了钒铬渣粒度、碳酸钠用量、焙烧时间、焙烧温度对钒、铬转浸率的影响规律。研究结果表明,钠化焙烧最佳条件为钒铬渣粒度-0.074 mm、碳酸钠用量50%~53%、焙烧时间60~70 min和焙烧温度790~850℃,获得的钒、铬转浸率分别为98.31%和93.53%。钠化焙烧后,钒铬渣中的钒铬铁尖晶石、铁橄榄石、玻璃相等物相基本消失,生成的主要物相为钒铬酸钠、钠辉石、氧化铁等。

Based on the theoretical analysis and thermodynamic calculations of chemical reactions for sodium roasting of vanadium-chromium slag,the simultaneous extraction of vanadium and chromium by high sodium and low temperature roasting was proposed.The effects of particle size of vanadium chromium slag,addition amount of sodium carbonate,roasting temperature and time on leaching rates of vanadium and chromium were researched.The results show that a rate of 98.31% and 93.53% respectively for vanadium and chromium leaching can be obtained at the optimum conditions for sodium roasting,i.e.less than 0.074 mm of the particle size of vanadium chromium slag,50%~53% of sodium carbonate addition,60~70 min of the roasting time and 790~850 ℃ of the roasting temperature.After sodium roasting,the phases of V-Cr-Fe spinel,iron olivine and glassy in vanadium-chromium slag disappear basically,mainly with the new phases of sodium vanadates,sodium chromates,sodium pyroxene and Fe2O3 formed.