萃取法分离回收不锈钢酸洗污泥硫酸浸出液中的重金属

采用非皂化P204和皂化P204萃取剂对不锈钢酸洗污泥的硫酸浸出液进行萃取。在浸出液pH为0.80、非皂化P204体积分数为25%、萃取剂与浸出液体积比为1∶2、萃取时间为5 min的条件下,Fe~(3+)萃取率达99.64%,Cr~(3+)和Ni~(2+)萃取率为3.98%和6.99%,一次萃余液pH为0.64。采用皂化P204对除Fe~(3+)后的一次萃余液进行萃取,在P204体积分数为25%、萃取剂与浸出液体积比为1∶2、萃取剂皂化率为60%、一次萃余液pH为1.50、萃取时间为5 min的条件下,Ni~(2+)萃取率为93.12%,Cr~(3+)萃取率为20.69%,二次萃余液pH为2.63。

Extraction and recovery of heavy metals from sulfuric acid leaching solution of stainless steel pickling sludge

The sulfuric acid leaching solution of stainless steel pickling sludge was extracted with non-saponified and saponified P204 extractant. Under the conditions of leaching solution pH 0.80,non-saponified P204 volume fraction 25%,volume ratio of extractant to leaching solution 1∶2 and extraction time 5 min,the extraction rate of Fe³⁺,Cr³⁺ and Ni²⁺ was 99.64%,3.98% and 6.99%,respectively,and the pH of raffinate was 0.64. The raffinate after Fe³⁺ removal was extracted with saponified P204 extractant and under the conditions of P204 volume fraction 25%,volume ratio of extractant to leaching solution 1∶2,saponification rate 60%,raffinate pH 1.50 and extraction time 5 min,the extraction rate of Ni²⁺ and Cr³⁺ was 93.12% and 20.69%,and the pH of the secondary raffinate was 2.63.