废催化剂中贵金属钒的浸出工艺

开展废催化剂的回收利用,不仅可以得高品位的贵金属,而且可以使废催化剂的有害部分减量化甚至无害化,解决相关环境污染问题。本课题对废催化剂中贵金属钒的浸出工艺进行研究,通过氧化焙烧—浸取法,可以从废催化剂中回收得到较纯的五氧化二钒。结果表明,氯化钠,硫酸钠,碳酸钠均不适合做焙烧过程的附加剂,焙烧工艺条件为:采用CaCO3作为焙烧附加剂,m(废催化剂):m(CaCO3)=1:8,焙烧温度1000℃,焙烧时间2.5 h,同时焙烧过程中要定时打开炉门放入一定量的空气,以保证四价钒充分氧化为五价钒,此时,钒浸出率最高可达94%左右。

Developing the recycling of spent catalyst can not only gain high-valued noble metal,but also cut down the harmful ingredients of the spent catalyst or make them harmless,hence the problem of environmental pollution could be solved.Leaching-out methodology of recycling vanadium from spent catalyst is studied in this paper.Relatively pure V2O5 is obtained by the method of roasting and leaching.The test result shows that NaCl,NaSO4 and Na2CO3 are not suitable additives in the roasting process.At last,CaCO3 is used as appropriate additive,the ratio of CaCO3 to spent catalyst in the material is 1 to 8,the roasting temperature is 1000℃,the spent catalyst is roasted for two hours and a half and then the door of the close roaster is opened to let the air into it to insure that there is enough oxygen which can oxidize V4＋ to V5＋;94% of vanadium can be precipitated.