Abstract Recovering microfine particle ilmenite using froth flotation is extremely challenging. In this study, the flotation behaviors of microfine particle (−38 μm) ilmenite untreated or treated with lead ions using sodium oleate as a collector were studied. Micro-flotation experiments revealed that the ilmenite presented superior floatability at pH 5.5. Pb(NO3)2 increased the flotation recovery by~12%. Solution component analysis indicated that the presence of lead ions depressed the dissolution of Fe and Ti metal ions on the ilmenite surface. The dominant Pb(II) species and RCOOH(I) were responsible for ilmenite flotation. Zeta potential measurements suggested that the RCOOH (I) and RCOO− ions mainly reacted with Fe and Pb on the ilmenite surfaces through electrostatic effects in addition to chemical adsorption. Fourier-transform infrared spectroscopy analysis showed that the new PbOL complex was formed on the ilmenite surfaces. X-ray photoelectron spectroscopy confirmed that the treatment of sulfuric acid promoted the valence transitions of iron ions. The proportion of the surface covered by Fe3+eventually increased from 32.51% to 63.22%. Time-of-flight secondary ion mass spectrometry (ToF–SIMS) provided strong evidence for the increased adsorption of oleate species on the ilmenite surfaces. Accordingly, the intensity of C4H7+ increased from 16,447 to 21089. New insights into lead ions activation for microfine particle ilmenite flotation in sulfuric acid system were mainly attributed to the oxidization of SO42− ions and the reinforced absorption of molecule/colloid oleate and PbOL complex compounds.

中文翻译：

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硫酸系统中微细颗粒钛铁矿浮选铅离子活化的新见解：Visual MINTEQ 模型、XPS 和 ToF-SIMS 研究

摘要 使用泡沫浮选法回收微细颗粒钛铁矿极具挑战性。在这项研究中，使用油酸钠作为捕收剂，研究了未处理或用铅离子处理的超细颗粒 (-38 μm) 钛铁矿的浮选行为。微浮选实验表明，钛铁矿在 pH 值为 5.5 时表现出优异的可浮性。Pb(NO3)2 使浮选回收率提高了约 12%。溶液成分分析表明，铅离子的存在抑制了钛铁矿表面 Fe 和 Ti 金属离子的溶解。主要的 Pb(II) 物种和 RCOOH(I) 负责钛铁矿的浮选。Zeta 电位测量表明，除化学吸附外，RCOOH (I) 和 RCOO− 离子主要通过静电效应与钛铁矿表面上的 Fe 和 Pb 反应。傅里叶变换红外光谱分析表明在钛铁矿表面形成了新的 PbOL 配合物。X 射线光电子能谱证实硫酸处理促进了铁离子的价态跃迁。Fe3+覆盖的表面比例最终从32.51%增加到63.22%。飞行时间二次离子质谱（ToF-SIMS）为钛铁矿表面上油酸盐物质的吸附增加提供了强有力的证据。因此，C4H7+ 的强度从 16,447 增加到 21089。 硫酸系统中微细颗粒钛铁矿浮选铅离子活化的新见解主要归因于 SO42− 离子的氧化和分子/胶体油酸盐和 PbOL 络合物的吸收增强.