Simulation assisted characterization of kaolinite–methanol intercalation complexes synthesized using cost-efficient homogenization method

Abstract Recent experimental and simulation findings with kaolinite–methanol intercalation complexes raised the question of the existence of more stable structures in wet and dry state, which has not been fully cleared up yet. Experimental and molecular simulation analyses were used to investigate different types of kaolinite–methanol complexes, revealing their real structures. Cost-efficient homogenization methods were applied to synthesize the kaolinite–dimethyl sulfoxide and kaolinite–urea pre-intercalation complexes of the kaolinite–methanol ones. The tested homogenization method required an order of magnitude lower amount of reagents than the generally applied solution method. The influence of the type of pre-intercalated molecules and of the wetting or drying (at room temperature and at 150 °C) procedure on the intercalation was characterized experimentally by X-ray diffraction and thermal analysis. Consistent with the suggestion from the present simulations, 1.12-nm and 0.83-nm stable kaolinite–methanol complexes were identified. For these complexes, our molecular simulations predict either single-layered structures of mobile methanol/water molecules or non-intercalated structures of methoxy-functionalized kaolinite. We found that the methoxy-modified kaolinite can easily be intercalated by liquid methanol.