The flotation separation of bastnaesite and monazite is challenging due to their similar physicochemical properties and floatability. In this work, an environmentally friendly depressant, dextrin hydrate (DH), was introduced for the flotation separation of bastnaesite from monazite using caprylhydroxamic acid (CHA) as the collector. The flotation behavior of bastnaesite and monazite in the absence and presence of DH was studied by micro-flotation tests. The mechanism was investigated by Zeta potential, Fourier infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The flotation results showed that monazite recovery decreased by 68.47% when the pH was 9.0 ± 0.2 and the amount of DH was 2.2 mg/L. In contrast, the bastnaesite recovery only exhibited a slight reduction of 7.98% under these conditions. Zeta potential analysis showed that DH had a strong effect on the subsequent adsorption of CHA on the surface of monazite but a minor effect on bastnaesite. FTIR and XPS analysis further confirmed that the chemisorption of DH on the Ce sites of monazite occurred. For bastnaesite, the adsorption of CHA still could be detected, making the bastnaesite well floatable. Therefore, the efficient separation of bastnaesite from monazite could be achieved with the DH as a selective depressant.

氟碳铈矿和独居石的浮选分离具有挑战性，因为它们具有相似的物理化学性质和可浮性。在这项工作中，使用辛基异羟肟酸 (CHA) 作为捕收剂，将环境友好型抑制剂水糊精 (DH) 引入浮选分离氟碳铈矿与独居石。通过微浮选试验研究了氟碳铈矿和独居石在不存在和存在 DH 的情况下的浮选行为。通过 Zeta 电位、傅立叶红外光谱 (FTIR) 和 X 射线光电子能谱 (XPS) 研究了该机理。浮选结果表明，当pH为9.0±0.2、DH用量为2.2mg/L时，独居石回收率降低了68.47%。相比之下，氟碳铈矿的回收率在这些条件下仅略微降低了 7.98%。Zeta 电位分析表明，DH 对随后 CHA 在独居石表面的吸附有很强的影响，但对氟碳铈矿的影响较小。FTIR 和 XPS 分析进一步证实了 DH 在独居石的 Ce 位点上发生了化学吸附。对于氟碳铈矿，仍然可以检测到CHA的吸附，使得氟碳铈矿具有良好的可浮性。 因此，使用 DH 作为选择性抑制剂可以实现氟碳铈矿与独居石的有效分离。