含铬电镀污泥的重金属酸浸特性研究

Leaching characteristics of heavy metals from chromium containing electroplating sludge

以含铬电镀污泥为研究对象,探究酸浸条件对重金属浸出的影响。考察了浸取剂种类、用量、浸取温度、浸取时间和振荡频率等因素对Cr、Ni、Zn浸出率的影响,选取4个因素进行正交实验。实验结果表明:硫酸与柠檬酸作为浸取剂的浸取效果比盐酸、硝酸和硼酸要好;选用硫酸作为浸取剂时,浸取剂用量为16 m L,浸取温度为35℃,浸取时间为2 h,振荡频率为50 r/m时,Cr、Ni、Zn的浸出率分别为76.37%、94.28%、91.23%;正交实验结果表明:浸取剂种类对重金属浸出影响最大,浸取剂用量次之;Cr、Ni、Zn三者的优化条件有所不同,优化后Cr、Ni、Zn的浸出率分别为96.89%、98.37%、97.52%。

in this paper the chrome containing sludge was taken as the object to explore the effect on leaching of heavy metals by acid leaching conditions,such as leaching agent,dosage,temperature,leaching time,oscillation frequency,and then 4 factors were selected for making the orthogonal test.The result showed that,when sulfuric acid and citric acid were used as leaching agent,the leaching rate was higher than that using nitric acid,hydrochloric acid,and boric acid. When the sludge was treated by 16 m L of sulfuric acid for 2 hours at 35℃ with the oscillation frequency of 50 rpm,the leaching rate for Cr,Ni and Zn was able to reach 76. 37%,94. 28%,and 91. 23% respectively.The orthogonal test revealed that type of leaching agent has the most important influence on the leaching rate,and followed by the dosage of leaching agent. The leaching rate of Cr,Ni,and Zn could reach 96. 89%,98. 37%,and 97. 52 % respectively under their own optimizing treatment conditions.