Abstract: Objective Coal kaolin is a mineral raw material with high purity and high crystallinity, which can be effectively broadened its application range after intercalation and compounding by organic matter. High-temperature calcination and modification can significantly enhance the adsorption effect of kaolin on heavy metal ions. MethodIn this work, coal kaolin intercalation complexes were prepared by liquid-phase intercalation method using potassium acetate as intercalating agent, and their adsorption properties on Pb(II) in water were investigated. Result The coal kaolin has the characteristics of structural order, high crystallinity, etc., which is suitable for interlayer modification. After high-temperature calcination and potassium acetate interlayer modification, the crystal spacing increases, which is conducive to the participation of potassium acetate in the interlayer, and the change of the crystal structure is not significant. Meanwhile, the agglomerating effect of the modified material is weakened, and the stacking property is enhanced, and the specific surface area is increased from 7.186 m²/g to 10.213 m²/g, which increases the probability of contacting with the heavy metal ions. The adsorption of Pb(II) by modified coal kaolin was significantly increased to 0.551 mg/g. ConclusionPotassium acetate intercalation modified coal kaolin has the advantages of cheap and easy availability and good adsorption performance, which is of positive significance in guiding the efficient recycling of coal kaolin.