Modification of kaolinite surfaces through mechanochemical treatment—a mid-IR and near-IR spectroscopic study

DRIFT spectroscopy has been used to study the changes in the molecular structure of kaolinite mechanochemically activated through dry grinding in the presence and absence of quartz. A comparison is also made with structure of mechanochemically activated kaolinite, which has been intercalated with potassium acetate. The effect of dry grinding with quartz causes the loss of intensity of the hydroxyl stretching and deformation bands of kaolinite to a much greater extent than for the kaolinite mechanochemically activated in the absence of quartz. The effect of intercalation upon the structure of the mechanochemically activated kaolinite is an apparent restructuring of the kaolinite layers. Two steps in the dehydroxylation of the kaolinite through mechanochemical activation and the hydration of the modified kaolinite surface are observed