Bastnaesite is a major light rare earth resource in the earth, which is difficult to separate from calcium-bearing gangue minerals in flotation because of their similar flotation characteristics as the semisoluble salt minerals. To address this problem, in 3-hydroxy-2-naphthyl hydroxamic acid (H205) system, the selective inhibition mechanism of oxalic acid on common calcium-bearing gangue minerals (calcite and fluorite) in bastnaesite flotation was studied by flotation tests, solution chemistry analysis, zeta potential measurements, and X-ray photoelectron spectroscopy (XPS) measurements, combined with thermodynamics and density functional theory (DFT) calculation. After the analysis of those tests and calculation results, it can be known that the hydrophilic oxalic acid can selectively compete with H205 for the active site (Ca²⁺) on the surface of the calcium-bearing gangue minerals, thus reducing its surface hydrophobicity and inhibiting its floating, while bastnaesite is not susceptible. In this process, fluorite is more inhibited than calcite.

氟碳铈矿是地球上主要的轻稀土资源，由于与半溶性盐类矿物具有相似的浮选特性，因此很难在浮选中与含钙脉石矿物分离。针对这一问题，在3-羟基-2-萘基异羟肟酸（H2O5）体系中，通过浮选试验、溶液化学等方法研究了草酸对氟碳铈矿浮选中常见含钙脉石矿物（方解石和萤石）的选择性抑制机制。分析、zeta 电位测量和 X 射线光电子能谱 (XPS) 测量，结合热力学和密度泛函理论 (DFT) 计算。通过对这些试验和计算结果的分析可知，亲水性草酸可以选择性地与 H2O5 竞争活性位点（Ca²⁺ ) 在含钙脉石矿物的表面，从而降低其表面疏水性并抑制其漂浮，而氟碳铈矿则不敏感。在这个过程中，萤石比方解石更受抑制。