Saponite with the incorporation of Zn^2＋ in the octahedral sheets were synthesized under non-hydrothermal condition of below 100 ℃ and at normal pressure by using urea for hydroxyl slow-releasing and pH controlling. The effects of n_Si/n_Al ratios, pH, crystallization time and temperature on the synthesis of Zn-saponite were studied. The synthesized samples were characterized by XRD, TEM and IR techniques. The reflection peaks of XRD pattern confirmed the trioctahedral layer structure of the product. The synthesized saponite with different n_Si/n_Al ratios (from 5.67 to 19) exhibited similar product phase and crystallinity. By adjusting initial mixture pH to 6, the unique saponite with high crystallinity could be synthesized at 90 ℃ for 12.5 h. The saponite grew preferentially on a- and b-axis plane direction. Based on the capability of ion exchange and the difference in sheet-charge, NiAl-HTLcs/saponite layer composites was synthesized through the intercalation of the HTLcs sheet to the interlayer of the two adjacent saponite sheets.

Key words: saponite, non-hydrothermal synthesis, hydrotalcite-like compound, intercalation