Abstract In this work, the activation mechanism of calcium species on the α-quartz surface was investigated. Microflotation, zeta potential measurements, first-principle calculation based on density functional theory (DFT), time-of-flight secondary ion mass spectrometry (ToF-SIMS) measurements and atomic force microscope (AFM) were conducted in this investigation. Sample preparation methods for minerals without a complete cleavage plane and reagent adsorption determination were introduced. Results revealed that quartz could be activated by calcium ions at the pH above 10, and calcium ion concentrations at pH below 10 slightly affected quartz recovery. Ca2+ could repel the hydration shell and hydroxylation on the quartz and be preferentially adsorbed onto the quartz surface at an alkaline pH. However, the coverage thickness and density of Ca2+ and the relevant coverage density of sodium oleate increased as the pH increased. The adsorbed amounts in the horizontal and vertical directions were also not uniform. The surface coverage thickness and density of Ca2+ and the corresponding amount of adsorbed sodium oleate played an important role in the activation of quartz. When the pH was above 10, the thickness and density of Ca2+ coverage on the quartz surface was sufficient, and Ca2+ could subsequently react with sodium oleate forming C18H33O2Ca. Thus, the quartz hydrophobicity was improved.

中文翻译：

---

钙物质对石英的激活机制的新见解：ToF-SIMS 和 AFM 研究

摘要 在这项工作中，研究了钙物质在α-石英表面的活化机制。在这项调查中进行了微浮选、zeta 电位测量、基于密度泛函理论 (DFT) 的第一性原理计算、飞行时间二次离子质谱 (ToF-SIMS) 测量和原子力显微镜 (AFM)。介绍了不完整解理面矿物的制样方法和试剂吸附测定。结果表明，石英可以在 pH 值高于 10 时被钙离子活化，而钙离子浓度在 pH 值低于 10 时对石英的回收率有轻微影响。Ca2+可以排斥石英上的水化壳和羟基化作用，在碱性pH条件下优先吸附在石英表面。然而，Ca2+的覆盖厚度和密度以及油酸钠的相关覆盖密度随着pH的增加而增加。水平和垂直方向的吸附量也不均匀。Ca2+的表面覆盖厚度和密度以及相应的油酸钠吸附量对石英的活化起着重要作用。当 pH 值大于 10 时，石英表面 Ca2+ 覆盖的厚度和密度足够，随后 Ca2+ 可以与油酸钠反应形成 C18H33O2Ca。因此，石英疏水性得到改善。Ca2+的表面覆盖厚度和密度以及相应的油酸钠吸附量对石英的活化起着重要作用。当 pH 值大于 10 时，石英表面 Ca2+ 覆盖的厚度和密度足够，随后 Ca2+ 可以与油酸钠反应形成 C18H33O2Ca。因此，石英疏水性得到改善。Ca2+的表面覆盖厚度和密度以及相应的油酸钠吸附量对石英的活化起着重要作用。当 pH 值大于 10 时，石英表面 Ca2+ 覆盖的厚度和密度足够，随后 Ca2+ 可以与油酸钠反应形成 C18H33O2Ca。因此，石英疏水性得到改善。