石煤钒矿硫酸活化常压浸出提钒工艺

Process of vanadium extraction from stone coal vanadium ore by activated sulfuric acid leaching at atmospheric pressure

研究石煤钒矿的硫酸活化提钒方法。分别考察矿石粒度、硫酸浓度、活化剂用量、催化剂用量、反应温度、反应时间和浸出液固比等因素对钒浸出率的影响。结果表明:石煤提钒的优化条件为矿石粒度小于74μm的占80%、硫酸浓度150 g/L、活化剂CaF2用量(相对于矿石)60 kg/t、催化剂R用量20 g/L、反应温度90℃、反应时间6 h、液固比(体积/质量,mL/g)2:1,在此优化条件下,钒浸出率可达94%以上;在优化条件下,采用两段逆流浸出,可有效减少活化剂CaF2以及浸出剂硫酸的消耗量;经过两段逆流浸出萃取反萃氧化水解工艺,全流程钒资源总回收率可达86.9%;V2O5产品纯度高于99.5%。

The method of activated sulfuric acid leaching of stone coal vanadium ore was studied.The effects of the ore particle sizes,sulfuric acid concentration,amount of active agent and catalyst agent,reaction temperature,reaction time and liquid to solid ratio on the leaching rate of vanadium were investigated,respectively.The results show that the optimal conditions of leaching vanadium from stone coal are as follows： stone coal with size less than 74 μm accounting for 80%,sulfuric acid concentration 150 g/L,dosage of active agent（relative to ore） CaF2 60 kg/t,dosage of catalyst R 20 g/L,reaction temperature 90 ℃,reaction time 6 h and liquid to solid ratio（volume/mass,mL/g） 2：1.Under the best condition,the leaching rate of vanadium can be higher than 94%.Under the optimum condition,the two-stage counter-current leaching process was employed,and the dosages of sulfuric acid and active agent CaF2 can be saved.The total recovery rate of vanadium is 86.9% throughout the whole process of two-stage counter-current leaching-solvent extraction-stripping-oxydrolysis.The purity of product V2O5 is higher than 99.5%.