摘要
为了控制电镀行业污染、减少重金属离子排放、加强资源利用,研究了pH值对电镀废水中重金属离子浸出的影响.将电镀废水用氢氧化钠溶液逐渐调节废水pH值,在多个pH值点分别沉淀出电镀废水中铜、铬、锌和镍.结果表明,随溶液pH值的升高,溶液中的铜、铬、锌和镍先沉淀后又部分溶解,实际操作中应将pH值控制在9.0～9.5范围内.电镀污泥经酸浸后,常温下电动搅拌1 h,在浸出液中加入锰铁合金块可直接还原铜、镍和锌离子,调节pH值至9.5时,可沉淀出铁、锰、铬混合金属氢氧化物.
In order to control the pollution of the electroplating industry, reduce the emissions of heavy metal ions, and improve resource utilization, the effects of pH on the leaching of heavy metal ions in electroplating wastewater is studied. Copper, chromium, zinc and nickel are precipitated at various pH, by gradually adjusting the pH of electro- plating wastewater with sodium hydroxide solution. It shows that hydroxides of copper, chromium, zinc and nickel precipitate first and dissolves with the pH value increasing. The actual operation is that Cu, Zn, Cr and Ni are precip- itated at pH = 9.0-9.5. After electroplating sludge acid leaching, Fe-Mn alloy is used as reducing agent to reduce low melting point heavy metal ions of copper, nickel and zinc. Adjusting pH to 9.5, the mixed hydroxides of Fe, Mn and Cr can be precipitated.
出处
《南通大学学报（自然科学版）》
CAS
2012年第4期46-49,共4页
Journal of Nantong University(Natural Science Edition)
基金
南通大学自然科学基金项目(10Z016)
关键词
PH值
电镀废水
重金属回收
金属离子
pH value
electroplating wastewater
heavy metal recovery
metal ions
