A new approach ‘dynamic contact angle analysis’ has been used in the present investigation to characterize the hydrophobization mechanisms of single and mixed surfactants on muscovite surface. The hydrophobization of muscovite surface was achieved by anionic NaOL (sodium oleate), cationic DDA (dodecylamine) and combined DDA/NaOL surfactants. Besides dynamic contact angle analysis, AFM and flotation tests were carried out to gain detail information about the wettability of muscovite, adhesion ability of bubbles towards muscovite surface and adsorption of single and mixed DDA/NaOL surfactants on the muscovite surface. From flotation results, the highest recovery (>90%) was obtained by the mixed DDA/NaOL when they were used at a ratio of 1:3 and the concentration of 2 × 10⁻⁴ mol/L. The dynamic contact angle tests showed that the angles achieved by DDA/NaOL were bigger and the bubbles were adhered more easily, which are in agreement with the flotation results. AFM imaging indicated that, as compared to single collectors, the combined surfactants adsorbed uniformly on the muscovite surface as bulks and formed a tight adsorption multilayer. The attraction in mixed DDA/NaOL was stronger than that in single DDA with the same jump-in distance at around 15 nm and the long-range repulsion was observed in single NaOL.

一种新的方法“动态接触角分析”已用于本研究中，以表征白云母表面上单一和混合表面活性剂的疏水化机理。白云母表面的疏水化是通过阴离子NaOL（油酸钠），阳离子DDA（十二烷基胺）和DDA / NaOL组合表面活性剂实现的。除了动态接触角分析之外，还进行了AFM和浮选测试，以获取有关白云母的润湿性，气泡对白云母表面的粘附能力以及单一和混合DDA / NaOL表面活性剂在白云母表面的吸附的详细信息。根据浮选结果，当DDA / NaOL以1：3的比例和2×10 ^-4的浓度使用时，回收率最高（> 90％） 摩尔/升。动态接触角试验表明，DDA / NaOL的夹角更大，气泡更容易附着，与浮选结果吻合。原子力显微镜成像表明，与单个收集器相比，结合的表面活性剂均匀地吸附在白云母表面，形成了紧密的吸附多层。在相同的跳入距离约为15 nm的情况下，混合DDA / NaOL的吸引力要强于单个DDA，并且在单个NaOL中观察到了长程排斥力。