用[Omim]Cl离子液体从钒渣水浸液中萃取分离钒试验研究

Solvent Extraction of Vanadium From Vanadium Slag Leaching Solution by Chloro-1-octyl-3-methylimidazolium Ionic Liquid

研究了以正戊醇为稀释剂、[Omim]Cl离子液体为萃取剂、氯化铵溶液为反萃取剂从钒渣水浸液中萃取分离钒,考察了萃取剂浓度、萃取时间、水相pH、萃取温度对钒萃取率的影响,以及反萃取剂浓度、反萃取剂pH、反萃取时间对钒反萃取率的影响。结果表明:在[Omim]Cl质量浓度50.0g/L、萃取时间30s、萃取温度25.0℃、水相pH=8.051条件下,钒萃取率为96.2%,萃取反应自发放热;以NH4Cl为反萃取剂,在NH4Cl浓度1.5mol/L、反萃取剂pH=8.5、反萃取时间30.0min条件下,钒反萃取率达98.06%;反萃取得到的NH4VO3固体经洗涤、烘干、煅烧得到纯度较高的五氧化二钒。

The solvent extraction and separation of V(Ⅴ)from a vanadium slag leaching solution using n-pentanol as diluents,chloro-1-octyl-3-methylimidazolium ionic liquid as extractant and ammonium chloride as stripping agent was studied.The effects of extractant concentration,contact time,solution pH and temperature on extraction of V(Ⅴ),and influences of concentration of back-extraction NH 4 Cl,pH and stripping time on stripping of V(Ⅴ)were examined.The results show that at the conditions of extractant concentration of 50.0 g/L,contact time of 30 s,temperature of 25.0℃and solution pH of 8.051,the extraction of V(Ⅴ)is 96.2%.The extraction process of vanadium is exothermic and spontaneous.The back-extraction of V(Ⅴ)is 95.84%at the conditions of NH 4 Cl concentration of 1.5 mol/L,pH of 8.5,stripping time of 30.0 min.The NH 4 VO 3 obtained by back-extraction is calcined,the vanadium pentoxide is obtained.