Beaussart Audrey, Mierczynska-Vasilev Agnieszka, Beattie David A
Ian Wark Research Institute, ARC Special Research Centre for Particles and Material Interfaces, University of South Australia, Mawson Lakes SA 5095, Australia.
Langmuir. 2009 Sep 1;25(17):9913-21. doi: 10.1021/la9010778.
The adsorption of dextrin on talc, molybdenite, and graphite (three naturally hydrophobic minerals) has been compared. Adsorption isotherms and in situ tapping mode atomic force microscope (TMAFM) imaging have enabled polymer adsorbed amount and morphology of the adsorbed layer (area coverage and polymer domain size) to be determined and also the amount of hydration water in the structure of the adsorbed layer. The effect of the polymer on the mineral contact angles, measured by the captive bubble method on cleaved mineral surfaces, indicates clear correlations between the hydrophobicity reduction of the minerals, the adsorbed amount, and the surface coverage of the adsorbed polymer. Predictions of the flotation recovery of the treated mineral phases have been confirmed by performing batch flotation experiments. The influence of the polymer surface coverage on flotation recovery has highlighted the importance of this key parameter in the predictions of depressant efficiency. The roles of the initial hydrophobicity and the surface structure of the mineral basal plane in determining adsorption parameters and flotation response of the polymer-treated minerals are also discussed.
已对糊精在滑石、辉钼矿和石墨（三种天然疏水矿物）上的吸附进行了比较。吸附等温线和原位敲击模式原子力显微镜（TMAFM）成像能够确定聚合物的吸附量和吸附层的形态（面积覆盖率和聚合物域尺寸），以及吸附层结构中的水合水量。通过在劈开的矿物表面上用俘获气泡法测量聚合物对矿物接触角的影响，表明矿物疏水性降低、吸附量和吸附聚合物的表面覆盖率之间存在明显的相关性。通过进行分批浮选实验，证实了对处理过的矿物相浮选回收率的预测。聚合物表面覆盖率对浮选回收率的影响突出了这一关键参数在抑制剂效率预测中的重要性。还讨论了矿物基面的初始疏水性和表面结构在确定聚合物处理矿物的吸附参数和浮选响应中的作用。
