不同萃取体系分离微生物浸出液中低含量镍钴

采用P507一Cyanex272混合萃取体系分离微生物浸出液中的镍钴,实验结果表明该体系具有较好的协萃效应.结合低含量镍钴的微生物浸出液体系高酸度、低钴镍比的特点,对比了P507、Cyanex272和P507-Cyanex272三种萃取体系对镍钴的萃取分离效果,确定了在初始pH值1.5~2.2、对应的平衡pH值4.00~5.25条件下P507-Cyanex272协萃体系有较好的镍钴分离效果.系统考察了室温28℃下协萃体系各影响因素对镍钴分离的影响,确定协同萃取的最佳工艺为:P507与Cyanex272摩尔比3:2,皂化率60%,萃取剂体积分数10%,有机相(由萃取剂与煤油组成)和水相体积比1:4.在此条件下钻的一级萃取率为99.16%,镍钻分离系数为932.59.

Separating low-content nickel and cobalt in bioleaching solution by different extraction systems

Separation of nickel and cobalt from bioleaching solution was studied using a synergistic extraction system of P507 and Cyanex272. Test results indicate that the system has a better extraction effect. Combined with the system characteristic of high acidity and low cobalt-to-nickel ratio, the separation effect of nickel and cobalt was compared in three extraction systems of P507, Cyanex272, and P507-Cyanex272. P507-Cyanex272 was identified to have a good separation effect of nickel and cobalt at the initial pH value of 1.5 to 2.2 and the balance pH value of 4.00 to 5.25. Influence factors on separation of nickel and cobalt in the extraction system at 28℃ were examined systematically, and the best processes for this synergistic extraction are the P507/Cyanex272 mole ratio of 3:2, the saponification rate of 60%, the extractant volume fraction of 10%, and the organic to aqueous phase ratio of 1:4. Under these conditions, the first extraction rate of cobalt is 99.16%, and the separation factor of nickel and cobalt is 932.59.