Abstract: Chinese coal-series kaolin is rich in reserves. To meet the needs of industries such as papermaking and textiles, it usually needs to be further processed. The optimum conditions for the preparation of coal-series kaolin/DMSO intercalated composites were explored using Shanxi Shuozhou coal-series kaolin as raw materials under constant temperature magnetic stirring and ultrasonic waves. Ultrasonic assisted stripping of coal-series kaolins was carried out on the basis of intercalated composites to prepare kaolin fine powder and XRD, SEM, BET, TG-DSC and other methods were used to analyze and characterize the sample. Orthogonal experimental results show that the amount of DMSO, intercalation time and intercalation temperature all have certain effects on the intercalation rate under magnetic stirring conditions. The ultrasonic wave is beneficial to the process of intercalation of kaolin. The thickness of the grains of the intercalation composites after ultrasonic assisted exfoliation are significantly reduced. The lamellar structure and edges of few kaolinite with large lamellar structure are both fragmented, and the the tendency of cracking is obvious. The specific surface area and pore size of exfoliated sample has been increased twice, providing new ideas for the exfoliation of hard kaolin and the preparation of ultrafine powder.

Key words: coal-series kaolin micropowder, ultrasonic assist, lamellar structure, exfoliation, ultrafine powder