Preparation of kaolinite nanotubes by a solvothermal method

Abstract

Kaolinite nanotubes were prepared by intercalation and solvothermal reactions using pristine kaolin as a starting material. Firstly, an intercalation compound of kaolinite/dimethyl sulfoxide was prepared as a precursor. Then, kaolinite/methanol (KM) was achieved by replacing dimethyl sulfoxide with methanol through solvothermal reaction at 100°C. Dimethyl sulfoxide molecules can be replaced mostly when the reaction time was 2h, and the intercalation ratio of KM compound reached 97.9% for the reaction time of 24h. Finally, the kaolinite nanotubes were achieved by the solvothermal reaction of the KM compound and methanol solution of CTAC (1M) at 100°C for 24h. XRD, IR, SEM, and N2 sorption measurements were used to characterize the as-prepared samples. It is found that the kaolinite nanotubes had a specific surface area of 45.44m2/g. The length of the nanotubes is about 300–2000nm and the internal diameter and external diameter is about 15–55nm and 40–80nm, respectively.