Abstract Dodecylamine hydrochloride (DAHC) surfactant was used as a collector for effective apatite recovery through flotation separation in siliceous phosphate ore, wherein quartz is the main gangue mineral. The roles of pH and collector concentration were investigated, and the adsorption of the collector on the minerals and related properties were systematically studied by measuring zeta potential, contact angle, surface tension, and adsorption density. When the collector concentration was 5 × 10−5 M, 23.7% P2O5 grade was achieved for a conditioning time of 10 min. However, the separation performance of the flotation was lower at pH 7 regardless of the collector concentration. Thus, more collector molecules are adsorbed on the quartz surface than the apatite surface at pH 3 and 5 × 10−5 M of collector, resulting in separation of quartz and apatite. The extended Derjaguin–Landau–Verwey–Overbeek (DLVO) theory, which considers the hydrophobic interaction energy, revealed that the improved flotation performance is attributed to a hydrophobic attractive force that is a consequence of the collector adsorption. Therefore, the results of flotation of artificially mixed minerals further revealed that optimization of the amine collector concentration and pH value can selectively separate quartz from apatite.

中文翻译：

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石英与磷灰石的浮选分离和气泡-颗粒相互作用中的表面力：pH 值和阳离子胺捕收剂含量的作用

摘要 使用盐酸盐十二胺（DAHC）表面活性剂作为捕收剂，在硅质磷矿中通过浮选分离有效回收磷灰石，其中石英是主要的脉石矿物。研究了pH和捕收剂浓度的作用，并通过测量zeta电位、接触角、表面张力和吸附密度，系统地研究了捕收剂对矿物的吸附及相关性质。当捕收剂浓度为 5 × 10-5 M 时，在 10 分钟的调节时间内达到 23.7% P2O5 等级。然而，无论捕集剂浓度如何，浮选的分离性能在 pH 7 时较低。因此，在 pH 3 和 5 × 10-5 M 的收集器上，石英表面吸附的收集器分子比磷灰石表面吸附的多，导致石英和磷灰石的分离。考虑疏水相互作用能的扩展的 Derjaguin-Landau-Verwey-Overbeek (DLVO) 理论表明，改进的浮选性能归因于疏水吸引力，这是捕收剂吸附的结果。因此，人工混合矿物的浮选结果进一步揭示了胺类捕收剂浓度和pH值的优化可以选择性地将石英与磷灰石分离。