从含钴萃余液中制取粗氢氧化钴的试验研究

Study on preparation of crude cobalt hydroxide from cobalt raffinate

利用活性氧化镁浆沉淀含钴萃余液中钴离子制取粗氢氧化钴,存在沉钴产品质量不稳定的问题。针对此问题,本文考察了氧化镁质量浓度、反应温度、反应终点pH值、钴离子浓度、铜离子浓度和洗涤液固比对氢氧化钴滤饼中钴含量和镁含量的影响。条件试验结果表明:活性氧化镁浆质量浓度在2%~10%时对粗氢氧化钴质量影响不大;沉钴反应温度高于45℃、反应终点pH值高于7.3有助于提高沉钴效率;溶液中钴离子浓度越高,铜离子浓度越低,越有助于提高粗氢氧化钴产品中的钴含量。工业生产实践表明,杂质镁含量较高的粗氢氧化钴产品经过清水洗涤后,产品质量可以稳定达到行业二等品标准。

The method of preparing crude cobalt hydroxide by using active magnesium oxide slurry to precipitate cobalt ions in the cobalt raffinate has the problem of unstable cobalt product quality when using the low-cobalt solution as raw material. In response to this problem,this paper investigated the effects of magnesium oxide mass concentration,reaction temperature,end pH,cobalt and copper ion concentration,washing liquid-solid ratio on the cobalt content and magnesium content in the cobalt hydroxide. The results show that it has little effect on the quality of crude cobalt hydroxide when the mass concentration of active magnesium oxide is 2% ~ 10%. It will improve the efficiency of preparation of crude cobalt when the temperature and end pH reach 45 ℃ and 7. 3,respectively. In addition,the higher concentration of cobalt ions and the lower concentration of copper ions are in the solution,the more cobalt grade is in the crude cobalt hydroxide. Industrial production shows that crude cobalt hydroxide which contains higher magnesium can reach the industry second-class product standards after being washed with water.