富钒溶液直接制备高纯V_2O_5的实验研究

Experimental Study on Direct Preparation of High Purity V2O5 from Vanadium⁃Rich Solution

采用磷酸铵镁法净化含钒富集液,脱除硅、磷,考察了除杂剂加入量、温度、pH值、铵镁比、反应时间等因素对杂质去除率的影响。结果表明,最佳净化除杂条件为:100 mL含钒富集液中加入200 g/L的氯化铵溶液8 mL,按铵镁比1.4加入氯化铵,直接使用原溶液(pH≈10.2)于室温下搅拌净化30 min后过滤得净化液,除磷率达到96%以上,除硅率达到87%,钒损失率可控制在2%左右。经过沉钒、过滤、洗涤、烘干、煅烧后,获得了纯度99.93%的高纯五氧化二钒。经重复性试验验证,此工艺稳定可靠、流程简单,而且生产成本低,可为高纯V_2O_5制备提供技术方案。

The vanadium⁃enriched liquid was purified by magnesium ammonium phosphate to remove silicon and phosphorus,and the effects of the adding amount of impurity remover,temperature,pH value,ammonium⁃magnesium ratio,reaction time and other factors on the removal rate of impurities were investigated.The results show that after adding 8 mL of magnesium chloride solution(200 g/L)and some prepared ammonium chloride with ammonium⁃magnesium ratio of 1.4,100 mL vanadium⁃enriched solution(pH≈10.2)was directly stirred at room temperature and then subjected to a 30⁃minute purification.The purified solution was obtained after filtration,showing the phosphorus removal rate over 96%and the silicon removal rate up to 87%,with the vanadium loss rate controlled at about 2%.After the processes of vanadium precipitation,filtration,washing,drying and calcination,the vanadium pentoxide with a purity of 99.93%was obtained.It is verified with repeated experiments that this processing technique is stable and reliable,with simple process and low production cost,which can provide a technical alternative for the preparation of high⁃purity V2O5.