复杂钼矿石中钼的化学物相分析

Chemical phase analysis of molybdenum in complex molybdenum ore

目前我国针对钼矿石进行物相分析时一般主要选择先溶解氧化钼,将留在残渣中的钼相计为硫化钼,但对于复杂钼矿石,这种操作会导致部分难溶的胶态氧化钼被计为硫化钼而使测定结果不准确,误导选矿工艺的制定。准确分离硫化钼和这部分难溶矿物中钼是钼矿石化学物相分析方法和选矿工艺亟待解决的问题。某地钼矿石因含有与金红石嵌连关系十分复杂的胶态氧化钼,无法通过传统化学物相分析方法浸出。实验以该地区的钼矿石为研究对象,通过实验探讨了使用王水作为浸取剂分离硫化钼和这部分难溶矿物中钼的方法,实现了硫化钼的准确定量分析。结果表明,采用45%(V/V)王水,于80℃水浴上反应2.0h的条件浸取硫化钼,能较好地分离出硫化钼。对钼矿各相态结果进行精密度考察,硫化钼相的钼测定结果的相对标准偏差(RSD,n=6)为0.13%,残渣部分难溶矿物中钼的RSD(n=6)为1.8%;相态合量与总钼测定结果一致;且分离测定的硫化钼分布率69.56%与经矿物自动解离分析仪(MLA)鉴定结果70%一致,实验结果能正确指导选矿工艺。

At present,the molybdenum oxide is firstly dissolved during the phase analysis of molybdenum ore in China.Then the molybdenum phase in residue is considered as molybdenum sulfide.For the complex molybdenum ore,however,partial insoluble colloidal molybdenum oxide would be calculated as molybdenum sulfide,leading to inaccurate measurement results and misdirection for the beneficiation process.Hence,how to accurately separate molybdenum sulfide and molybdenum in this part of insoluble ore has become an urgent issue in chemical phase analysis of molybdenum ore and beneficiation process.One molybdenum ore sample from a certain deposit containes colloidal molybdenum oxide which has a very complex contact relationship with rutile,and it cannot be leached using the traditional chemical phase analysis method.The molybdenum ore from this area was selected as the research object.The aqua regia was used as the leaching reagent for the separation of molybdenum sulfide and this part of colloidal molybdenum oxide.Consequently,the accurate quantitative analysis of molybdenum sulfide was achieved.The results showed that molybdenum sulfide could be well separated under the following leaching conditions:45%(V∶V)aqua regia,reaction in water bath at 80℃for 2.0h.The precision tests of determination results of various phases in molybdenum ore were conducted.The relative standard deviation(RSD)of molybdenum sulfide phase was 0.13%,while the RSD of molybdenum in insoluble residue was 1.84%.The sum of phases was consistent with the determination result of total molybdenum.Moreover,the distribution rate of molybdenum sulfide(69.56%)was in agreement with the result from mineral liberation analysis(MLA),i.e.,70%.The proposed method could correctly guide the mineral processing process.