反浮选法分离粉石英和斜绿泥石及其机理

Separation of clinochlore from powder quartz by reverse flotation and its mechanism

采用油酸作阴离子捕收剂,用反浮选的方法对粉石英的纯化进行研究,探讨粉石英和斜绿泥石的分离机理以及捕收剂的吸附机理。实验中测定粉石英和斜绿泥石的ζ电位、pH值、油酸浓度、浮选时间对SiO2回收率和纯度的影响;分析粉石英、斜绿泥石的晶体结构和表面性质以及油酸作阴离子捕收剂时的溶液化学。结果表明：在pH为8-0的碱性溶液中,粉石英难与金属阳离子缔合,所以,不与油酸根离子结合;而斜绿泥石解离后层间存在活性金属阳离子,可与油酸根离子发生化学吸附产生疏水作用,因而使用反浮选的方法能有效地实现二者的分离;当pH为9时,斜绿泥石的去除率最高,粉石英的纯度达99.86%,回收率为35%。

The purification of powder quartz was studied through reverse flotation by using oleic acid as the anionic collector. The separation mechanisms of powder quartz and clinochlore as well as the adsorption mechanism of the anionic collector were investigated. In the experiment, if-potential of the two minerals were measured, and the effects of pH, concentration of oleic acid and flotation time on the purity and recovery of SiO2 were tested. Furthermore, the crystal structure, surface characters of quartz and clinochlore, and the solution chemistry of oleic acid as the anionic collector were analyzed. The results show that quartz cannot react with oleic irons at pH=8-10, because it is difficult to combine with metallic irons. On the contrary, clinochlore can adsorb with oleic ions because there are enough active metallic positive ions between the minerals layers which can combine with clinochlore. The clinochlore can be hydrophobic, and so the separation can be realized finally. At pH=9, the clinochlore removal rate is the maximum, the purity of SiO2 is 99.86%, and the recovery of SiO2 is 35%.