工业含铬废水的络合萃取处理工艺研究

Removing chromium from industrial wastewater by complexing extraction

采用络合萃取法处理工业含铬废水 ,考察了起始pH、流速和接触时间等对络合萃取处理效果的影响 ,探讨了铬盐生产废水和电镀废水的处理工艺。结果表明 ;在废水起始pH为 1 0～ 2 0时 ,络合萃取法能方便、快速、有效地去除废水中的六价铬。络合萃取 碱沉淀法适用于六价铬含量远大于三价铬含量的电镀废水的处理 ,氧化 络合萃取法可用于三价铬含量较高的电镀废水的处理。

Complexing extraction of chromate ions from industrial wastewater was studied.The influences of the initial pH of the aqueous phase,the velocity of wastewater flow,and the contact time between complexing extraction granule and wastewater were discussed,and the treating technology of chromate industrial wastewater and electroplating wastewater was also studied.Experimental results showed that the proper inital pH of the aqueous phase is about 1.0～2.0,complexing extraction method can extract Cr^(6+) from wastewater conveniently,fleetly and effectively,and Cr^(6+) can be also reclaimed easily.Two steps operation of complexing extraction can make high concentration chromate industrial wastewater up to the national discharge standards.Complexing extraction-alkali precipitation method can be used to treat electroplating wastewater which the concentration of Cr^(6+) is far more than that of Cr^(3+),contrarily oxidation-complexing extraction method may be used.