Abstract In this paper, the separation of tungsten and molybdenum by selective precipitation is evaluated, and the addition of cetyltrimethyl ammonium bromide (CTAB), as complex agent, is developed to reduce Mo loss. Thermodynamic equilibrium calculations show that manganese salt has selectivity to precipitate tungsten from molybdenum. Through single factor experiments, the influence of precipitation factors is studied systematically. The results show that CTAB can enhance the separation of molybdenum and tungsten by manganese salts. Under optimal conditions (temperature 50 °C, n(Mo)/n(CTAB) = 2, n(Mo)/n(W) = 10, time 1 h), the loss rate of Mo is 0.73%, the precipitation rate of W is 89.57%, and the separation factor is 2411.67, which is much higher than the separation factor of molybdenum and tungsten without CTAB. The results of XRD and SEM show that the precipitates mainly consist of MnWO4 and a small amount of MnMoO4 with the shape of the flower cluster composed of flakes. The complex effect of CTAB is verified by the simulation of Cambridge sequential total energy package (CASTEP). The results of geometric optimization, total energy and density of states together with FTIR spectra reveal the complex mechanism of CTAB with MoO42−. As an inexpensive and green sorbent, CTAB can be used to enhance the effect of manganese salt precipitation method for selective separation of W and Mo ions.

中文翻译：

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在十六烷基三甲基溴化铵 (CTAB) 的辅助下，使用硫酸锰选择性沉淀分离钨和钼

摘要 本文对选择性沉淀法分离钨和钼进行了评价，并开发了添加十六烷基三甲基溴化铵（CTAB）作为络合剂以减少钼损失。热力学平衡计算表明，锰盐具有从钼中沉淀钨的选择性。通过单因素试验，系统地研究了降水因素的影响。结果表明，CTAB 可以提高锰盐对钼和钨的分离效果。在最佳条件下（温度50℃，n(Mo)/n(CTAB)=2，n(Mo)/n(W)=10，时间1h），Mo损失率为0.73%，析出率W的为89.57%，分离系数为2411.67，远高于不含CTAB的钼和钨的分离系数。XRD和SEM结果表明，析出物主要由MnWO4和少量MnMoO4组成，呈片状花簇状。CTAB的复合效应通过剑桥序贯总能量包（CASTEP）的模拟得到验证。几何优化、总能量和态密度以及 FTIR 光谱的结果揭示了 CTAB 与 MoO42− 的复杂机制。作为一种廉价的绿色吸附剂，CTAB 可用于增强锰盐沉淀法选择性分离 W 和 Mo 离子的效果。几何优化、总能量和态密度以及 FTIR 光谱的结果揭示了 CTAB 与 MoO42− 的复杂机制。作为一种廉价的绿色吸附剂，CTAB 可用于增强锰盐沉淀法选择性分离 W 和 Mo 离子的效果。几何优化、总能量和态密度以及 FTIR 光谱的结果揭示了 CTAB 与 MoO42− 的复杂机制。作为一种廉价的绿色吸附剂，CTAB 可用于增强锰盐沉淀法选择性分离 W 和 Mo 离子的效果。