铁精矿浮选脱硅过程中, 矿浆中的难免阳离子(Ca2+, Fe3+)对阴离子捕收石英的可浮性有重要影响, 而搞清难免阳离子对含石英等脉石矿物的活化机制, 对解决超纯铁精矿脱硅技术难题有重要意义。 目前关于捕收剂对石英吸附结构的研究较多, 而难免离子活化石英的吸附结构及吸附强弱发生机制研究较少。 因此, 采用红外光谱、 XPS检测手段对难免离子(Ca2+, Fe3+)活化石英浮选进行光谱学表征, 同时解析石英中含氧官能团及难免离子的赋存形式, 分析其活化机理。 红外检测结果表明, 在适宜的pH值条件下, Ca2+和Fe3+的加入, 对SDS捕收剂浮选石英均有活化作用, 而活化后的石英与SDS作用, 其间既包括物理吸附, 也包括化学吸附; 而且Fe3+活化作用下的Si-O特征峰红移波数大于Ca2+活化作用下的红移波数, 是由于Ca2+活化石英是单氧-硅键作用, 其键能小, 吸附弱, 而Fe3+活化石英是双氧-硅键作用, 其键能大, 吸附强。 XPS测试表明, Fe3+活化石英的结合能(Fe(2p)结合能为711.16 eV)强于Ca2+活化石英的结合能(Ca(2p)结合能为346.93 eV), 其Si(2s)和Si(2p)结合能化学位移量更大, 说明Fe3+活化作用下其化学吸附更稳定、 更致密, 且产生两个活性位点, 在石英表面生成稳定的Fe基六元环螯合物; 而对比Fe3+和Ca2+活化作用下的化学吸附不稳定、 不致密, 在石英表面生成Ca基链状络合物。 综合红外光谱、 XPS分析表明, Fe3+比Ca2+有更强的活化作用, 同时加强了药剂与石英表面的化学吸附和物理吸附, 更利于活化石英的浮选。

During the flotation desilication of iron concentrate, the unavoidable cations (Ca2+, Fe3+) in the pulp have important influences on the floatability of quartz using the anion collecter, and it is of great significance to find out the activation mechanism of the unavoidable cations on the quartz and other pulsar minerals to solve the technical problem of desilication of ultra-pure iron concentrate. At present, there are many pieces of research on the adsorption structure of quartz for collectors, while there are few pieces of research on the adsorption structure and the occurrence mechanism of adsorption strength for inevitable ion-activated quartz. So infrared spectroscopy and XPS analysis were adopted, the spectral characterization of unavoidable ions (Ca2+, Fe3+) activated quartz were performed, and the occurrence forms of oxygen-containing functional groups and unavoidable ions in quartz were analyzed, the mechanism of unavoidable ions activated quartz were also analyzed. The results show that in the infrared characterization, at the appropriate pH value, the addition of Ca2+ and Fe3+ activates the flotation of quartz. When quartz is activated by Ca2+ and Fe3+ and reacts with SDS, the chemical adsorption and physical absorption occur almost at the same time. And the red-shifted wave numbers of Si-O characteristic peak under Fe3+ activation is stronger than that of Ca2+ activation. Ca2+ can activate quartz is due to mono- silicon bond, and the bond action has small bond energy and weak adsorption; Fe3+ activated quartz is due to a dioxy-silicon bond, which has large bond energy and strong adsorption. The XPS test results show that the binding energy of Fe3+ activator activated quartz (Fe(2p) binding energy of 711.16 eV) is stronger than that of Ca2+ activated quartz (Ca(2p) binding energy of 346.93 eV), which makes the chemical displacement of Si(2s) and Si(2p) binding energy larger. It is indicated that the stable Fe-based six-membered ring chelate is formed on the surface of quartz under the activation of Fe3+, and chemical adsorption is more stable and dense, and two active sites are generated; while the unstable Ca-based s chain-like complex is formed on the surface of quartz under the activation of Ca2+, and chemical adsorption is unstable and not so dense. Comprehensive infrared spectrum and XPS analysis show that Fe3+ has stronger activation than Ca2+, and enhance the chemical and physical adsorption between the agent and quartz surface, which is more conducive to the flotation of activation quartz.