摘要
钒电解液是钒电池储能系统的关键材料,钒电解液中Mn,Cr,Ti等杂质元素含量对钒电池性能影响很大。高纯V_(2)O_(5)作为钒电解液的重要原料,主要从钒渣钠化焙烧-水浸或者钙化焙烧-酸浸两种工艺获得。本文选取钙化焙烧-酸浸含钒浸出液进行研究,针对其中Mn,Cr,Ti等杂质离子的除杂,形成浸出液水解沉钒—碱溶和净化—铵盐沉钒—煅烧的工艺流程,制备高纯V_(2)O_(5)。确定优化的钒浸出液水解沉钒制备粗V_(2)O_(5)条件为:反应时间为2.0 h,反应pH值为2.2,反应温度为80℃;将获得的粗V_(2)O_(5)进行碱溶二次净化,在优化条件为:NaOH浓度为1%,碱溶终点pH值为8.0,加入阴离子型絮凝剂,温度为60℃时,Mn,Cr,Ti等杂质均得到进一步去除;以经过二次净化后的钒浸出液为原料,在条件为反应时间为60 min,pH值为2.0,温度为90℃,加铵系数(K)为1.2时制备多钒酸铵,再得到高纯V_(2)O_(5),Mn,Cr,Ti等杂质离子都得到了有效去除。
High-purity V_(2)O_(5) is one of the key raw materials of vanadium battery energy storage system,and its demand is increasing withthe development of vanadium battery energy storage technology.At present,China mainly uses converter vanadium slag as the raw materi-al to obtain vanadium-containing leachate through two processes of sodiumization roasting-water leaching or calcification roasting-acidleaching,and then prepare V_(2)O_(5),and then remove impurities to prepare high-purity V_(2)O_(5).Because there are many associated elements inthe vanadium slag,they will be enriched in the leaching solution with vanadium,which will reduce the purity of the vanadium pentoxideproduct,and then affect the performance of the vanadium electrolyte.Theoretically,depending on the vanadium extraction process,thecomposition of the vanadium leaching solution will be different.The metal ions contained in the vanadium leaching solution may includeV,Fe,Mn,Cr,Ti,Na and Ca,and the non-metal ions may include Si,P,S,etc.,these elements not only have variable valence,but alsomay form complex heteropolyacid ions with other ions or ion groups.Using a suitable extractant or exchange resin could recover vanadiumand obtain its high-purity product,but the large amount of extraction method and ion exchange reagent and the long process could not meetthe large-scale production of high-purity V_(2)O_(5) products.At present,the impurity removal of vanadium leaching solution was only a onestep impurity removal,that was,to remove a specific impurity by adjusting the p H or adding a coprecipitation agent,but the impurities ofMn,Cr,and Ti were still high,and the V_(2)O_(5) produced was not suitable for preparing vanadium electrolysis.The main content of this exper-iment included three parts:hydrolysis precipitation of vanadium leaching solution,dissolution and purification of crude vanadium pentox-ide,and vanadium precipitation by ammonium salt.Firstly,the raw materials of the leachate were hydrolyzed to precipitate vanadium toobtain crude vanadium pentoxi
作者
张国权
陶忍
秦志峰
彭穗
Zhang Guoquan;Tao Ren;Qin Zhifeng;Peng Sui(State Key Laboratory of Vanadium and Titanium Resources Comprehensive Uilization,Panzhihua 617000,Chi-na;School of Chemical Engineering,Sichuan University,Chengdu 610065,China)
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2021年第1期70-76,共7页
Chinese Journal of Rare Metals
基金
国家自然科学基金项目(51774205)
钒钛资源综合利用国家重点实验室开放课题项目(18H0063)
川大-攀枝花校市合作项目(2018CDPZH-6)
四川省科技厅应用基础研究项目(2019YJ0111)
四川钒钛产业发展研究中心开放课题(2018VTCY-Y-01)资助。
关键词
高纯五氧化二钒
钒浸出液
化学沉淀净化
沉钒
high-purity vanadium pentoxide
vanadium leaching solution
chemical precipitation purification
vanadium precipitation
