Mixed hydroxy-Al-Fe pillared montmorillonites with large basal spacing were successfully prepared through cation-exchanging of Na +- montmorillonite with mixed hydroxy-Al and hydroxy-Fe pillaring solutions made from ...Mixed hydroxy-Al-Fe pillared montmorillonites with large basal spacing were successfully prepared through cation-exchanging of Na +- montmorillonite with mixed hydroxy-Al and hydroxy-Fe pillaring solutions made from hydrolysis of corresponding metal salts, followed by calcination to convert hydroxy-Al and hydroxy-Fe into intercalated polycations. According to XRD analysis, the basal spacing d(001) of pillared products dramatically enlarged from 12.7 *! in the Na-montmorillonite to 81 *! in the hydroxy-Fe -montmorillonite and 77.5 *! in mixed hydroxy-Al-Fe-montmorillonite. The N_2 BET surface areas of the pillared montmorillonites also greatly increased to more than 200 m 2/g as compared to about 27 m 2/g for the Na-montmorillonite. IR analysis of hydroxy-Fe, and mixed hydroxy-Al-Fe pillared montmorillonites revealed a new absorption vibration at 1384 cm -1 wavelength. XRF elemental analysis data also showed a high content of Fe_2O_3 in the hydroxy-Fe pillared montmorillonite.展开更多
Al-pillared interlayered montmorillonite (Al-PILM) was prepared using the artificial Na-montmorillonite from the Qingfengshan bentonite mine as a starting material mixed with Al-pillaring solutions.The microstructure ...Al-pillared interlayered montmorillonite (Al-PILM) was prepared using the artificial Na-montmorillonite from the Qingfengshan bentonite mine as a starting material mixed with Al-pillaring solutions.The microstructure of the materials was studied by an X-ray powder diffractometer and a Fourier transform infrared (FTIR) spectrometer.The results indicated that the basal spacing [d(001) value] of the materials was increased significantly to 1.9194 nm relative to Na-montmorillonite (1.2182 nm).After calcined for 2 h at 300℃,the basal spacing was stabilized at 1.8394 nm and the layered structure of the materials was not destroyed.Thermal analysis was conducted by a thermal gravimetry and differential thermal analysis (TG-DTA) instrument,it showed that Al-PILM lost physically adsorbed water below 230.6℃ and water formed by dehydroxylation of the pillars at around 497.1℃, with a peak of the phase transformation at 903.0℃.展开更多
Al-Cr-pillared montmorillonite was synthesized by using bentonite and Al-Cr pillaring solutions as starting materials.The basal spacing and specific surface areas of the materials were significantly increased relative...Al-Cr-pillared montmorillonite was synthesized by using bentonite and Al-Cr pillaring solutions as starting materials.The basal spacing and specific surface areas of the materials were significantly increased relative to those of untreated clays.When the Al/Cr molar ratio(R) was 0.10,the d(001) value and specific surface area of pillared montmorillonite were 1.9194 nm and 165.7 m2 g -1,respectively.Thermal stability of the materials was determined using calcined tests and X-ray diffraction (XRD) analysis.The materials formed at different R(0.05;0.10;0.15;0.25) exhibit a high thermal stability at 300℃,especially at initial R=0.10,the basal interlayer spacing of materials is stabilized at 1.7313 nm after calcined at 500℃ for 2 h.Adsorption behavior of the materials was studied by adsorption experiments.The results show that the Al-Cr-pillared montmorillonites exhibit much stronger adsorption capacity on Cr 6+ in aqueous solution than untreated clays do.展开更多
Al-Mn-pillared montmorillonite(AMPM) was prepared by using the artificial Na-montmoril-lonite from the Qingfengshan bentonite mine as starting materials mixed with Al-Mn pillaring solutions at different Al/Mn molar ra...Al-Mn-pillared montmorillonite(AMPM) was prepared by using the artificial Na-montmoril-lonite 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 montmoril-lonite were 1.8987 ran 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℃. 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.展开更多
Through cation exchanging of montmorillonite, mixed hydroxy Fe Al pillared montmorillonites with large basal spacing were synthesized. The application of these mixed hydroxy Fe Al pillared montmorillonites as adsorben...Through cation exchanging of montmorillonite, mixed hydroxy Fe Al pillared montmorillonites with large basal spacing were synthesized. The application of these mixed hydroxy Fe Al pillared montmorillonites as adsorbents in the areas of environmental protection and pollution control was investigated. Adsorption of Direct Green B, an organic dye, on OH—Fe—, OH—Al—, OH—Fe—Al— pillared montmorillonites was studied. Results showed that these pillared montmorillonites had much better adsorption properties than traditional Na organo montmorillonite. It was also found that pH of the solutions had great effect on the performance of these hydroxy metal pillared montmorillonites in treating the wastewater containing Direct Green B.展开更多
文摘Mixed hydroxy-Al-Fe pillared montmorillonites with large basal spacing were successfully prepared through cation-exchanging of Na +- montmorillonite with mixed hydroxy-Al and hydroxy-Fe pillaring solutions made from hydrolysis of corresponding metal salts, followed by calcination to convert hydroxy-Al and hydroxy-Fe into intercalated polycations. According to XRD analysis, the basal spacing d(001) of pillared products dramatically enlarged from 12.7 *! in the Na-montmorillonite to 81 *! in the hydroxy-Fe -montmorillonite and 77.5 *! in mixed hydroxy-Al-Fe-montmorillonite. The N_2 BET surface areas of the pillared montmorillonites also greatly increased to more than 200 m 2/g as compared to about 27 m 2/g for the Na-montmorillonite. IR analysis of hydroxy-Fe, and mixed hydroxy-Al-Fe pillared montmorillonites revealed a new absorption vibration at 1384 cm -1 wavelength. XRF elemental analysis data also showed a high content of Fe_2O_3 in the hydroxy-Fe pillared montmorillonite.
文摘Al-pillared interlayered montmorillonite (Al-PILM) was prepared using the artificial Na-montmorillonite from the Qingfengshan bentonite mine as a starting material mixed with Al-pillaring solutions.The microstructure of the materials was studied by an X-ray powder diffractometer and a Fourier transform infrared (FTIR) spectrometer.The results indicated that the basal spacing [d(001) value] of the materials was increased significantly to 1.9194 nm relative to Na-montmorillonite (1.2182 nm).After calcined for 2 h at 300℃,the basal spacing was stabilized at 1.8394 nm and the layered structure of the materials was not destroyed.Thermal analysis was conducted by a thermal gravimetry and differential thermal analysis (TG-DTA) instrument,it showed that Al-PILM lost physically adsorbed water below 230.6℃ and water formed by dehydroxylation of the pillars at around 497.1℃, with a peak of the phase transformation at 903.0℃.
文摘Al-Cr-pillared montmorillonite was synthesized by using bentonite and Al-Cr pillaring solutions as starting materials.The basal spacing and specific surface areas of the materials were significantly increased relative to those of untreated clays.When the Al/Cr molar ratio(R) was 0.10,the d(001) value and specific surface area of pillared montmorillonite were 1.9194 nm and 165.7 m2 g -1,respectively.Thermal stability of the materials was determined using calcined tests and X-ray diffraction (XRD) analysis.The materials formed at different R(0.05;0.10;0.15;0.25) exhibit a high thermal stability at 300℃,especially at initial R=0.10,the basal interlayer spacing of materials is stabilized at 1.7313 nm after calcined at 500℃ for 2 h.Adsorption behavior of the materials was studied by adsorption experiments.The results show that the Al-Cr-pillared montmorillonites exhibit much stronger adsorption capacity on Cr 6+ in aqueous solution than untreated clays do.
基金Supported by Foundation for University Key Teacher by the Ministry of Education
文摘Al-Mn-pillared montmorillonite(AMPM) was prepared by using the artificial Na-montmoril-lonite 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 montmoril-lonite were 1.8987 ran 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℃. 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.
文摘Through cation exchanging of montmorillonite, mixed hydroxy Fe Al pillared montmorillonites with large basal spacing were synthesized. The application of these mixed hydroxy Fe Al pillared montmorillonites as adsorbents in the areas of environmental protection and pollution control was investigated. Adsorption of Direct Green B, an organic dye, on OH—Fe—, OH—Al—, OH—Fe—Al— pillared montmorillonites was studied. Results showed that these pillared montmorillonites had much better adsorption properties than traditional Na organo montmorillonite. It was also found that pH of the solutions had great effect on the performance of these hydroxy metal pillared montmorillonites in treating the wastewater containing Direct Green B.
