Yuan Ji-zu

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

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.

Synthesis and Characteristics of Organic Bentonite Gel

The bentonite was modified using Cabentonite as a matrix and octadecyl/hexadecyl ammonium chloride as the cover agent, based on hydrothermal process. The organic gel with 5.0 Pa · s viscosity was synthesized by dispersing it into the dimethyl benzene-methyl alcohol system fully. The optimum process conditions for organic modification were that the coating agent dosage is 22 g/L, reaction time is 90 minutes and the pH value of pulp is 10. X-ray diffraction (XRD) analysis indicates that the d (001) value of the modified bentonite is 20. 532 Å. The influence of gel temperature on its viscosity characteristic was studied. By analyzing the transmssion electron microscopy (TEM) images and observing the dispersed gel, the nanometer effect of the organic gel was discussed.