The structure difference of the flotation reagent has a significant influence on its flotation performance. In this work, sodium N-lauroyl glycinate (SNG) was synthesized by introducing an acyl group into sodium N-dodecylglycinate (SN), and was using the collector in the oxide ores flotation. Properties of these two collectors were compared, and the effects behavior and mechanism of introducing the acyl group on the flotation performance of alkylglycine-based collectors to the zinc oxide minerals were systematically investigated. Flotation results proved that the introduction of C = O group into SN barely affected the floatability of smithsonite, hemimorphite and calcite, while the floatability of quartz was greatly reduced. Contact angle tests, surface tension tests, and froth collapse measurements indicated that the introduction of the acyl group into SN could selectively weaken its ability to improve the hydrophobicity of mineral surfaces, reduce its surface tension, adsorption capacity and intensity on the mineral surface, and the froth stability, thereby enhancing its selectivity, consistent with the flotation results. Fourier transform infrared spectroscopy (FTIR) analyses and density functional theory (DFT) calculations revealed that the introduction of the acyl group could increase the cross-sectional area and reduce the charge of the SNG polar groups to selectively weaken the adsorption interaction, particularly by significantly reducing the electrostatic adsorption between SNS and quartz surfaces. These also confirm that SNG is a promising highly selective collector for the flotation separation of zinc oxide minerals.

中文翻译：

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酰基对烷基甘氨酸基捕收剂浮选性能的影响及机理研究


浮选药剂的结构差异对其浮选性能有显著影响。在本工作中，通过将酰基引入 N-十二烷基甘氨酸钠 （SN） 中合成了 N-月桂酰甘氨酸钠 （SNG），并在氧化物矿石浮选中使用捕收剂。比较了这两种捕收剂的性质，并系统研究了引入酰基的行为和机理对烷基甘氨酸基捕收剂浮选性能的影响。浮选结果表明，在 SN 中引入 C = O 基团对史密森石、半晶石和方解石的可浮性几乎没有影响，而石英的可浮性大大降低。接触角试验、表面张力试验和泡沫塌陷测量表明，酰基引入SN会选择性地削弱其提高矿物表面疏水性的能力，降低其表面张力、矿物表面的吸附能力和强度以及泡沫稳定性，从而提高其选择性，与浮选结果一致。傅里叶变换红外光谱 （FTIR） 分析和密度泛函理论 （DFT） 计算表明，酰基的引入可以增加横截面积并减少 SNG 极性基团的电荷，从而选择性地削弱吸附相互作用，特别是通过显着减少 SNS 和石英表面之间的静电吸附。这些也证实了 SNG 是一种很有前途的高选择性捕收剂，用于氧化锌矿物的浮选分离。