Preparation and properties of pillared montmorillonite by polyhydroxyl-aluminum-manganese cations

Abstract

Al−Mn-pillared montmorillonite (AMPM) was prepared by using the artificial Na-montmorillonite from the Qingfengshan bentonite mine as starting materials mixed with Al−Mn pillaring solutions at different Al/Mn molar ratios (R). The basal spacing and specific surface area of the materials were increased significantly compared with untreated clays. When R=0.5, the d(001) value and specific surface area of pillared montmorillonite were 1.8987 nm and 146.01 m2 g−1, respectively. The thermal stability was determined using calcined tests, X-ray diffraction (XRD) analysis, thermal gravimetry and differential thermal analysis(TG-DTA). The materials formed at initial R=0.5 exhibited a high stability, the basal interlayer spacing was stabilized at 1.7859 nm after calcined for 2 h at 300°C. The adsorption behavior of the materials was studied by adsorption experiments. The results show the AMPM and calcined Al−Mn-pillared montmorillonite(CAMPM) exhibit a strong capacity of adsorbing the Zn(II) in aqueous solution at pH 10.0.