Substituent Effects in Kaolinite Flotation Using Dodecylamine: Experiment and DFT Study

The molecular structure of cationic surfactants is closely related to their flotation performance. In this paper, three with different head group structures were selected as collectors kaolinite, and the substituent effects studied by DFT method. calculation results showed that increasing number substituents in dodecylamine can significantly increase its surface charge. Dodecylamine has lowest LUMO orbital energy, so strongest electron attraction ability interaction kaolinite. Electron density differential there was an area aggregation between collector energy DDA on kaolinite surfaces greater than other two collectors, indicating adsorption more stable. Flotation higher a yield obtained presence dodecyl dihydroxyethyl methyl ammonium chloride. calculated solvent-accessible surfaces, charge, bonds show good consistency actual which be used screening index for collectors.