含镍废液制备硫酸镍并深度除Fe、Cu、Zn

摘要

本文以镀镍行业产生的含Fe、Cu、Zn等杂质的硫酸镍废液为原料,通过采用氧化、化学沉淀、P204多级萃取等低成本的方法,实现了Fe、Cu、Zn等主要杂质的深度去除,制备出符合HG/T 2824-2009中Ⅰ类一等品的硫酸镍产品.试验重点考察了双氧水用量用量对除铁的影响,以及中和pH值、萃取pH值、萃取相比等技术参数对Fe、Cu、Zn、Ni除杂率的影响,并按照最佳条件处理了一批10 L废液得到2300 9硫酸镍产品,一次结晶率达60％.试验结果表明:用双氧水氧化后石灰中和至pH值5.0,Fe离子沉淀完全;在中和终点pH值4.5 ～5.7范围内,Fe、Cu、Ni的沉淀率随pH值的增大而增大,Zn的变化不大;pH值达5.7,Cu的沉淀率达98.4％;P204对金属离子的萃取顺序为:Fe3+ ＞Zn2+＞Cu2+＞Fe2+＞Ni2+;P204可有效萃取分离Fe、Cu、Zn等杂质;经萃取分离后硫酸镍溶液中Fe、Cu、Zn的含量全部达到10-3g/L以下.%In this paper,the nickel sulfate wastewater containing Fe,Cu and Zn produced by nickel plating industry was used as a raw material.Nickel sulfate product,which conformed to HG/T 2824-2824 Ⅰ classes firsts,was prepared by Oxidation process,Chemical precipitation,P204 extraction that were used to deep removal of Fe,Cu,Zn.The influence of hydrogen peroxide dosage,neutralization pH,extraction pH,O/A and other technical parameters on Fe,Cu,Zn and Ni removal were tested.According to the best conditions,10 L wastewater was treated and 2300 g nickel sulfate products,whose crystallization rate was 60％,were prepared.The experimental results showed that:The solution was neutralized to PH 5.0 with lime,after oxidized by H2O2,Fe was precipitated completely.The deposition rates of Fe,Cu and Ni were increasing,while Zn hadn't changed much,with the increase of pH.The precipitation rate of Cu was 98.4％ at pH 5.7.The order of P204 extraction of metal ions is:Fe3+ ＞Zn2+ ＞Cu2+ ＞Fe2+ ＞Ni2+,and the content of Fe,Cu and Zn in nickel sulfate solution are all less than 10-3 g/L after extracted.