The recovery of fluorite from calcium-bearing carbonate ores by foam flotation is challenging due to low separation efficiency. Herein, we studied the effect of trisodium nitrilotriacetate (TN) addition on the surface properties of calcite and fluorite. For this purpose, we performed micro-flotation tests and carried out zeta potential measurements as well as Fourier transform infrared (FT-IR) and X-ray photoelectron (XPS) spectroscopic measurements to analyze the surface properties of these minerals.

The addition of TN as a novel depressor significantly improved the effect of calcite and sodium oleate (NaOl) on the flotation-based fluorite recovery and separation from calcite. TN interacted with fluorite via an electrostatic interaction according to the zeta-potential and XPS analyses. The interaction of TN with calcite was via electrostatic attraction and chemical adsorption. Preferential chemical adsorption of NaOl replaces TN from the fluorite surface. However, calcite preferentially adsorbs TN due to the chemical bonding between carboxyl of TN and the hydrated calcite surface layer, which chemically modifies the original calcite surface. This work also suggests interaction and adsorption mechanisms between TN and calcite.

由于分离效率低，通过泡沫浮选从含钙碳酸盐矿石中回收萤石具有挑战性。在此，我们研究了添加次氮基三乙酸三钠 (TN) 对方解石和萤石表面性质的影响。为此，我们进行了微浮选测试并进行了 zeta 电位测量以及傅里叶变换红外 (FT-IR) 和 X 射线光电子 (XPS) 光谱测量，以分析这些矿物的表面性质。

添加 TN 作为新型抑制剂显着改善了方解石和油酸钠 (NaOl) 对浮选萤石回收和方解石分离的影响。根据 zeta 电位和 XPS 分析，TN 通过静电相互作用与萤石相互作用。TN与方解石的相互作用是通过静电吸引和化学吸附。NaOl 的优先化学吸附取代了萤石表面的 TN。然而，由于 TN 的羧基与水合方解石表面层之间的化学键合，方解石优先吸附 TN，从而对原始方解石表面进行化学改性。这项工作还表明了 TN 和方解石之间的相互作用和吸附机制。