Abstract In this study, to improve the separation efficiency of magnesite from quartz, ethylenediamine tetra(methylene phosphonic acid) sodium (EDTMPS) was first introduced as a chelation depressant for the selective depression of magnesite in magnesite-quartz flotation system when using dodecylamine (DDA) as the collector. The results of micro-flotation tests indicated that EDTMPS selectively depressed magnesite flotation and achieved the separation of magnesite from quartz via reverse flotation. Contact-angle and zeta-potential measurements demonstrated that EDTMPS interfered with the interaction of DDA with magnesite rather than quartz, resulting in the low hydrophobicity of magnesite in the presence of DDA. Fourier-transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) analysis showed that EDTMPS could prevent DDA adsorption onto a magnesite surface could be attributed to selective chelation on Mg, but had only a slight impact on a quartz surface. Density functional theory (DFT) calculations further revealed that the interaction between DDA and magnesite was weakened by the pre-adsorption of EDTMPS; this observation was supported by the enlarged distance between N atoms for DDA and magnesite surface (from 2.636 A to 8.003 A) in the presence of EDTMPS. Based on these results, a possible model for the flotation separation process was proposed.

中文翻译：

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关于新型抑制剂 EDTMPS 在菱镁矿和石英表面的选择性抑制机制的新见解：吸附机制、DFT 计算和吸附模型

摘要 本研究为提高菱镁矿从石英中的分离效率，首次引入乙二胺四亚甲基膦酸钠 (EDTMPS) 作为螯合抑制剂，在菱镁-石英浮选系统中使用十二胺 (DDA) 选择性抑制菱镁矿。 ) 作为收集器。微浮选试验结果表明，EDTMPS选择性抑制菱镁矿浮选，通过反浮选实现菱镁矿与石英的分离。接触角和 zeta 电位测量表明，EDTMPS 会干扰 DDA 与菱镁矿而不是石英的相互作用，导致在 DDA 存在下菱镁矿的疏水性较低。傅里叶变换红外 (FTIR) 光谱和 X 射线光电子能谱 (XPS) 分析表明，EDTMPS 可以阻止 DDA 吸附到菱镁矿表面，这可归因于对 Mg 的选择性螯合，但对石英表面的影响很小。密度泛函理论（DFT）计算进一步表明，EDTMPS 的预吸附减弱了 DDA 与菱镁矿之间的相互作用；在 EDTMPS 存在下，DDA 和菱镁矿表面的 N 原子之间的距离扩大（从 2.636 A 到 8.003 A）支持了这一观察结果。基于这些结果，提出了浮选分离过程的可能模型。密度泛函理论（DFT）计算进一步表明，EDTMPS 的预吸附减弱了 DDA 与菱镁矿之间的相互作用；在 EDTMPS 存在下，DDA 和菱镁矿表面的 N 原子之间的距离扩大（从 2.636 A 到 8.003 A）支持了这一观察结果。基于这些结果，提出了浮选分离过程的可能模型。密度泛函理论（DFT）计算进一步表明，EDTMPS 的预吸附减弱了 DDA 与菱镁矿之间的相互作用；在 EDTMPS 存在下，DDA 和菱镁矿表面的 N 原子之间的距离扩大（从 2.636 A 到 8.003 A）支持了这一观察结果。基于这些结果，提出了浮选分离过程的可能模型。