Abstract To separate and enrich rare-earth elements (REE) minerals from their ores through flotation process has become an attracting topic for REE’s strategic position. In the present investigation, the floatability of bastnasite [(Ce,La)CO3F] was explored by using 1-hydroxydodecylidene-1,1-diphosphonic acid (HDDPA) as a collector. The micro-flotation results showed that bastnasite displayed an eminent floatability under pH 7.0–10.0, and HDDPA realized an efficient separation of bastnasite from calcite at pH around 8.0. Zeta potential and solution chemistry inferred that at pH 7.5–9.3, HDDPA3− anions were glad to replace the CO32- ions of Ce(Ⅲ) carbonates in/on bastnasite interface, resulting in a high flotation recovery of bastnasite. With increasing OH- concentration, the competition ability of OH- against HDDPA anion intensified, gradually the surface Ce(III) hydroxide species increased, and the floatability of bastnasite reduced. Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) recommended that the surface Ce(III) of bastnasite interacted with the O atoms of HDDPA’s O P(O)O group to generate a four membered ring configuration, which hydrophobized bastnasite particles.

中文翻译：

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氟碳铈矿的 1-Hydroxydodecylidene-1,1-diphosphonic acid 浮选：性能和机理

摘要 通过浮选工艺从矿石中分离和富集稀土元素(REE)矿物已成为稀土战略地位的一个吸引人的话题。在本研究中，使用 1-羟基十二烷-1,1-二膦酸 (HDDPA) 作为捕收剂，探索了氟碳 [(Ce,La)CO3F] 的可漂浮性。微浮选结果表明，氟碳铈矿在pH 7.0-10.0下表现出优异的可浮性，而HDDPA在pH 8.0左右实现了氟碳铈矿与方解石的有效分离。Zeta 电位和溶液化学推断，在 pH 7.5-9.3 时，HDDPA3− 阴离子很乐意取代氟碳铈矿界面上/上的 Ce(Ⅲ)碳酸盐的 CO32- 离子，导致氟碳铈矿的高浮选回收率。随着 OH- 浓度的增加，OH- 对 HDDPA 阴离子的竞争能力增强，表面的Ce(III)氢氧化物种类逐渐增多，氟碳铈矿的可浮性降低。傅里叶变换红外 (FTIR) 和 X 射线光电子能谱 (XPS) 表明，氟碳铈矿的表面 Ce(III) 与 HDDPA 的 OP(O)O 基团的 O 原子相互作用，生成四元环构型，从而疏水化氟钛矿颗粒.