电解锰铬钝化液循环利用工艺技术研究

Recycling and Utilization of Electrolytic Manganese Passivation Wastewater

以电解锰工艺末端铬钝化废液为研究对象,采用氧化-分离工艺降低废液中Cr3+、Mn2+的质量浓度以及提高Cr(Ⅵ)质量浓度,对其开展氧化和树脂吸附实验,研究电解锰生产过程中铬钝化液在线循环处理.结果表明,使用K2MnO4作氧化剂,可将废钝化液体系中的Cr3+转化为有效的Cr(Ⅵ),转化率达到86.0%,可返回钝化工序循环使用,Mn2+被转化为MnO2,转化率达到69.5%,生成的MnO2沉淀易分离,氧化-分离工艺能够实现电解锰钝化废液的净化和循环利用.

A series of experiments were carried out for chrome recycling and utilization by oxidation,adsorption and oxidation-separation technologies in K2Cr2O7 passivator of electrolytic manganese wastewater. The purpose was to reduce the level of trivalent chrome ion and manganese ion and to improve sexavalent chrome ion concentration simultaneously. The results showed that choosing potassium permanganate as the oxidant,trivalent chrome can be transformed to sexavalent chrome,the transformation ratio was 86. 0% which can be recycled in passivation process. Manganese ion can be transformed to manganese dioxide,the precipitation of which can be easily separated,and the transformation ratio was 69. 5%. The oxidation-separation technology can achieve purification and recycling of passivator of electrolytic manganese wastewater.