废弃SGR催化剂中有价金属回收的实验研究

发布时间：2018-05-21 19:54

  本文选题：废弃SCR催化剂 + 有价金属　； 参考：《华北电力大学》2015年硕士论文

【摘要】：废弃SCR催化剂中含有V、W和Ti等多种有价金属,直接弃置不仅会造成环境污染,还会造成资源的浪费,因此回收其中的有价金属具有重大意义。本文采用湿法冶金的方法,通过NaOH碱性浸出法一次性浸出废弃催化剂中的V和W,余下未溶解的固体主要成分为二氧化钛,从而将Ti分离;然后对浸出液进行钙化沉淀,通过甲酸选择性浸出钙混合沉淀物中的钒,经过除杂,加入氨水钒将以偏钒酸铵的形式沉淀出来;甲酸浸出后沉淀物中的钨,加入盐酸转化为钨酸,经过灼烧,最终生成三氧化钨。通过实验确定NaOH碱性浸出法最佳工艺条件为:对于钒,NaOH浓度为20%,固液比1:7,催化剂粒径125~180μm,温度50℃,浸出时间60min,钒的浸出效率达93%以上;对于钨,NaOH浓度为30%,固液比1:7,催化剂粒径125~180μm,温度60℃,浸出时间60min,钨的浸出效率达87%以上。对于甲酸选择性浸出过程,最佳反应条件为:温度30℃、pH=5、固液比1:5、反应时间40min,钒的浸出率为94.88%,同时钨的浸出率(损失率)仅为3.99%。从原料到产物钒和钨最终的回收率分别为:82.25%和78.48%,钛(含杂质)回收率超过99%。
[Abstract]:There are many valuable metals in the waste SCR catalyst, such as VN W and Ti, which will not only cause environmental pollution, but also cause waste of resources. Therefore, it is of great significance to recover the valuable metals. In this paper, using hydrometallurgical method, V and W in the waste catalyst were leached in one time by NaOH alkaline leaching method. Titanium dioxide was the main component of the remaining undissolved solid, and Ti was separated, then the leaching solution was calcified and precipitated. After selective leaching of vanadium from calcium mixed precipitate by formic acid, adding ammonia water vanadium will precipitate in the form of ammonium metavanadate; after formic acid leaching, the tungsten in the precipitate is converted into tungstic acid by adding hydrochloric acid, and after burning, the vanadium in the precipitate will be precipitated in the form of ammonium metavanadate. Finally, tungsten trioxide is formed. The optimum technological conditions of NaOH alkaline leaching method are as follows: for vanadium NaOH concentration 20, solid to liquid ratio 1: 7, catalyst particle size 125 ~ (180) 渭 m, temperature 50 鈩，

本文编号：1920538