镍基合金电解加工渣泥中镍和钴的回收

摘要

Recovery of nickel and cobalt from electromachining sludge of a nickel alloy was investigated. According to component of the sludge and thermodynamical analysis, the sludge was treated by using a washing—leaching—hydrolysis precipitation process. The results show that soluble compounds such as sodium chloride, sodium nitrate and a part of chromium salts can be washed out from the sludge. In the following sulphuric acid leaching process, nickel, cobalt and chromium in the washed sludge can be leached out, but tungsten and molybdenum remain in the leaching residue. Extraction ratio of nickel and cobalt in the leaching process amounts to 98%. The chromium in the leach solution can be removed as chromium hydroxide by using a hydrolysis-precipitation process and the efficiency of chromium removal reaches 94.44%.%根据镍基合金电解加工渣泥的组成和热力学分析， 用水洗—浸出—水解沉淀工艺处理这种渣泥。 试验结果表明： 氯化钠、 硝酸钠和部分铬盐等可溶性化合物可以从渣泥中洗出； 继而的硫酸浸出过程中， 可将洗后渣泥中的镍、 钴和铬浸出， 而钨和钼留在浸出渣中。 在浸出过程中， 镍和钴的浸出率达98%。 浸出液中的铬可通过水解沉淀法以氢氧化铬的形态除去， 铬的脱除率达94.44%。