摘要:
黏土钒矿是典型的难处理钒矿资源之一。以选矿富集的黑色页岩型黏土钒精矿为研究对象,研究硫酸配加助浸剂、氧化剂直接浸出黏土钒矿的工艺,并对酸浸影响因素条件进行优化。研究表明:高浓度硫-氟酸性溶液体系可以很好地破坏云母、黏土矿物、褐铁矿的结构,直接浸钒可行。在黏土钒矿粒度-74μm比例 ≥ 85%,浸出温度80~90℃、硫酸(含量98%)加入量54%、搅拌速度400 r/min,液固比L/S=2.5~4.0:1,氧化剂NaClO3用量1.25%,助浸剂CaF2用量12%、酸浸时间11 h的浸出优化条件下,V2O5的浸出率可达到90%以上,优于传统焙烧法。采用扩散渗析器回收硫酸和氟离子效果良好。
Abstract:
Vanadium-bearing clay mineral is one of typical vanadium resources which are difficult to utilize.The feasibility of direct leaching of black shale-hosted vanadium-bearing clay mineral concentrates by H2SO4-CaF2-NaClO3 system was studied.Furthermore,the influencing factors of leaching were investigated.The results show that H-SO4-F acid solution system with high concentration can effectively destroy the mineral structures of mica,clay minerals and limonite.Vanadium leaching rate reaches 90.0% or above with 85% of concentrates' sizes smaller than -74 μm,reaction temperature at 80℃,liquid to solid ratio(volume/mass,mL/g) of 2.5 to 4.0:1、H2SO4 (98%) addition amount higher than 54%, stirring speed of 400 r/min,NaClO3 addition amount of 1.25%,CaF2 addition amount of 12%,and leaching time of 11 h.under the conditions,vanadium leaching rate is higher than that of the traditional roasting method.sulfuric acid and fluoride ions can be effectively recovered by diffusion dialyzer.