Elimination of adverse effects of seawater on molybdenite flotation using sodium silicate
Elimination of adverse effects of seawater on molybdenite flotation using sodium silicate
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DOI：
10.1016/j.mineng.2019.106108
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发表时间：
2020-01
影响因子：
4.8
通讯作者：
Yinghao Peng;Yubiao Li;Wanqing Li;X. Fang;Cheng Liu;Rong Fan
中科院分区：
文献类型：
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作者：
Yinghao Peng;Yubiao Li;Wanqing Li;X. Fang;Cheng Liu;Rong Fan
由于淡水资源的匮乏，海水在矿物浮选过程中的应用越来越多。然而，海水对碱性条件下的硫化钼浮选有不利影响，但其影响机理尚不清楚，限制了其在浮选厂的应用。本研究以海水为浮选介质，以Ca2+和Mg2+为影响离子，添加水玻璃（SS），对二硫化钼进行浮选。与淡水中相比，海水中二硫化钼浮选回收率显著降低。此外，在0.05 M MgCl2溶液中的MoS2回收率显著低于在0.01 M CaCl2溶液中的MoS2回收率（这些浓度与海水一致），表明Mg2+比CaCl2起更有害的作用。SS的加入不同程度地提高了MoS_2的回收率，其中以0.05 M MgCl_2溶液中的提高最为明显。接触角、zeta电位、物种计算和XPS分析表明，浮选回收率的降低主要是由于钙镁络合物和沉淀物吸附在MoS2表面所致。此外，DLVO理论计算表明，SS通过将MoS2颗粒与Mg（OH）2胶体之间的相互作用力由吸引力逆转为排斥力，阻止了带正电的Mg沉淀在带负电的MoS2表面的吸附.该研究为利用海水浮选二硫化钼提供了新的思路。
Seawater has been increasingly applied in mineral flotation process due to the scarcity of freshwater. However, seawater plays an adverse effect on molybdenite (MoS2) flotation under alkaline condition, but the influencing mechanisms were still unclear, limiting its application in flotation plants. In this study, seawater, and the ions with the most influence of Ca2+and Mg2+were applied in MoS2flotation, with the addition of sodium silicate (SS). As compared to that in freshwater, MoS2flotation recovery was signifiantly decreased in seawater. In addition, MoS2recovery in 0.05 M MgCl2solution was significantly lower than that in the 0.01 M CaCl2solution (these concentrations being consistent with seawater), indicating that Mg2+plays a more detrimental role than that of CaCl2. The addition of SS increased MoS2recovery to different contents, with the most apparent being for that in 0.05 M MgCl2solution. Various measurements including contact angle, zeta potential, species calculation, and XPS analysis indicate that the decreased flotation recovery is primary due to the adsorption of Ca and Mg complexes and precipitates onto MoS2surface. Moreover, the DLVO theory calculation suggests that SS prevents the adsorption of positively charged Mg precipitates onto negatively charged MoS2surface by reversing the interaction force betwen MoS2particles and Mg(OH)2colloids from attraction to repulsion. This study therefore provides a new insight into utilizing seawater for MoS2flotation.