摘要
采用单矿物浮选、Zeta电位和芘荧光探针,研究由DDA和SDS组成的阴阳离子混合表面活性剂在不同的浮选条件下对长石、石英分离效能影响以及表面活性剂在矿物表面的吸附行为。结果表明:在相同浓度阴阳离子混合表面活性剂中,长石的疏水性要强于石英;Zeta电位在DDA∶SDS=1∶1时主要由阳离子决定,在DDA∶SDS=1∶2、1∶3时由阴离子决定。芘荧光探针结果表明:在pH=2.0,长石和石英表面极性在低浓度混合表面活性剂中与浓度呈负相关;在DDA∶SDS=1∶1、浓度为4×10-4 mol/L时,混合表面活性剂在矿物表面形成半胶束,且长石表面形成半胶束浓度低于石英。当DDA∶SDS=1∶2、1∶3时,长石表面形成半胶束浓度提高,而石英未能在实验条件内形成胶束。综合而言,在同一混合表面活性剂条件下,长石表面疏水性强于石英。
We investigated the effect of flotation conditions on the separating efficiency and adsorbing behaviors of quartz and feldspar with DDA and SDS as an anion-cation mixed surfactant using pure mineral samples to test flotation, Zeta potential and pyrene fluorescence. Results of the pure mineral flotation show that the hydrophobicity of feldspar is stronger than that of quartz in same measured quantity. Zeta potential tests indicate that the Zeta potential is determined by cations when DDA∶SDS=1∶1, while determined by anions when DDA∶SDS=1∶2 and 1∶3,. Pyrene fluorescence, under the condition of pH=2.0, shows that there is a negative correlation between surface polarity and quantity in lower quantities of mixed surfactant. When DDA∶SDS=1∶1 and solution is 4×10-4 mol/L, the mineral surface begins to form micelles, and the micelles form on the surface of feldspar are much lower than those on quartz. When DDA∶SDS=1∶2 and 1∶3, micelles of feldspar increases, while quartz unable to form micelles under the experimental conditions. In general, the hydrophobicity of feldspar is stronger than that of quartz under certain conditions of anion-cation mixed surfactant.
引文
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