镁离子对钼尾矿中石英和长石浮选分离的影响研究

为了回收内蒙古某钼尾矿中含量约35%的长石以及含量约35%的石英，进行了油酸钠在镁离子存在的条件下对石英和长石浮选分离的研究。通过对浮选条件的优化，在pH=11.0、镁离子用量300 g/t、油酸钠用量900 g/t的条件下，获得了产率为27.28%、SiO₂含量为94.67%的石英产品以及产率为36.47%、K₂O+Na₂O含量11.13%的长石产品。通过Zeta电位测试及镁离子的溶液化学分析表明，矿浆pH值为11.0时，Mg（OH）+的浓度较大，Mg（OH）₂沉淀刚开始生成，此时活化石英的效果最为明显，即浮选精选产率较大，且浮选精矿中长石浮选回收率较低；当矿浆pH值大于11.0时，在矿物表面生成越来越多的Mg（OH）₂沉淀可能使药剂失去选择性，从而导致大量长石开始上浮。镁离子对石英的活化作用有利于石英和长石的浮选分离。 

The Influence of Magnesium Ions on Flotation Separation of Quartz and Feldspar in Molybdenum Tailings

In order to recover about 35% feldspar and 35% quartz from a molybdenum tailings in Inner Mongolia, the flotation separation of quartz and feldspar by sodium oleate in the presence of magnesium ions was studied. Through the optimization of flotation conditions, at pH=11.0, Mg2+ ion dosage of 300 g/t, and sodium oleate dosage of 900 g/t, the quartz products with yield of 27.28%, SiO₂ content of 94.67% and feldspar products with yield of 36.47% and K₂O+Na₂O content of 11.13% were obtained. Zeta potential test and chemical analysis of magnesium ion solution showed that when the pH value of pulp was 11.0, the concentration of Mg(OH)+ was relatively high, and the precipitation of Mg(OH)₂ was just started to form. At this time, the activated anion collector had the most obvious effect of capturing quartz, that is, the yield of flotation concentratrate was high, and the recovery rate of feldspar flotation in the flotation concentrate was relatively low. When the pH value of the pulp is greater than 11.0, the formation of Mg(OH)₂ precipitation on the mineral surface may be an important reason for the loss of selectivity of the agent, leading to the large amount of feldspar beginning to float.