摘要
将电镀废水中的六价铬还原成Cr(III),用化学沉淀法和絮凝法将其转化为Cr(OH)3沉淀,通过硫酸酸化,结晶为高纯硫酸铬,作为皮革工业的铬鞣剂。分析了镀铬废水的絮凝效果、Cr(III)溶液絮凝前后杂质的含量及硫酸铬的纯度,选定了最佳pH。结果表明,使用回收后的硫酸铬进行铬鞣与使用标准铬粉进行铬鞣达到了同等水平,废水中铬的回收率高达92.8%。
The Cr(Ⅲ) was obtained by reducing Cr(Ⅵ) in the electroplating wastewater to Cr(Ⅲ), which was converted to Cr(OH)3 by means of chemical precipitation and flocculation methods. Using H2SO4 as acidulant, chromic sulfate with high purity was obtained by crystallization, which was applied to leather industry as chrome tanning agent. The flocculation effect of chrome plating wastewater, the content of impurities in Cr(Ⅲ) wastewater before and after flocculating and the purity of chromic sulfate were analyzed, and the optimal pH was determined. The results show that the same tanning effect was achieved by either using chromic sulfate recovered from wastewater or standard chrome powder. The recovery rate of chrome in wastewater reaches 92.8%.
出处
《电镀与涂饰》
CAS
CSCD
2007年第4期52-54,共3页
Electroplating & Finishing
关键词
镀铬废水
化学沉淀法
絮凝法
硫酸铬
皮革工业
铬鞣剂
( Institute of Chemistry & Chemical Engineering, Shanxi University of Science Technology, Xi'an 710021, China)