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
Both inorganic and organic pillared montmorillonites were used to adsorb phenol. Batch kinetics and isotherm studies were carried out to evaluate the effect of equilibrium time and pH on adsorption of phe- nol by mont...Both inorganic and organic pillared montmorillonites were used to adsorb phenol. Batch kinetics and isotherm studies were carried out to evaluate the effect of equilibrium time and pH on adsorption of phe- nol by montmorillonites and re-adsorbing characteristics of pillared montmorillonites. The adsorption of phenol increased with increasing solution pH values. The elimination ratio of phenol from the solution by the absorption of organic modified pillared montmorillonite (OrPMt) reached equilibrium quickly after vibrating for 5 minutes. Meanwhile for organic montmorillonite (OrMt), pillared montmorillonite (PMt) and montmorillonite (Mt), the time to reach phenol-absorption equilibrium were 20, 30 and 90 minutes, respectively. The adsorbing capacity of the pillared montmorillonite modified with surfactant improved greatly. The phenol-adsorbing capacity of pillared molltmorillonites mainly depended on microporous structure and surface component of the modified clays. After calcination at 500 ℃, the pillar structure and the basal spacing (1.83 um) were still stable. So the pillared montmorillonite could be recycled, and it was a potential material for adsorbing environmental pollutants.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
A mesoporous titanium/silicon -containing montmorillonite-based catalytic materials has been synthesized by novel gallery-templated techniques. XRD, SEM, framework IR, and N2 adsorptiondesorption isotherms provided e...A mesoporous titanium/silicon -containing montmorillonite-based catalytic materials has been synthesized by novel gallery-templated techniques. XRD, SEM, framework IR, and N2 adsorptiondesorption isotherms provided evidence of the formation of Si/Ti pillars. The synthetic materials show potential catalytic application for hydroxylation of phenol with peroxide.展开更多
A novel bisupported bimetal catalyst PVP-PdCl2-FeSO4/Al-Mont-PEG600 was prepared by immobilization of PVP (poly (N-vinyl-2-pyrrolidone)) supported bimetallic catalyst using alumina pillared inartificial montmorill...A novel bisupported bimetal catalyst PVP-PdCl2-FeSO4/Al-Mont-PEG600 was prepared by immobilization of PVP (poly (N-vinyl-2-pyrrolidone)) supported bimetallic catalyst using alumina pillared inartificial montmorillonite as the carrier. This catalyst has good dehalogenation activity and selectivity to aryl halides o-chlorotoluene in aqueous system in the presence of phase transfer catalyst (PEG) and sodium formate as hydrogen source. The catalyst also shows good reusability.展开更多
Nickel-substituted mica-montmorillonite clays(Ni-SMM) were synthesized, the pillared clays, Si-Ni-SMM, were prepared from the Ni-SMM intercalated with NH2(C3H5)Si(OC2H5)3.The pillar perhaps consists of tripolymer of s...Nickel-substituted mica-montmorillonite clays(Ni-SMM) were synthesized, the pillared clays, Si-Ni-SMM, were prepared from the Ni-SMM intercalated with NH2(C3H5)Si(OC2H5)3.The pillar perhaps consists of tripolymer of silica according to the judgement from the pillar height (8. 5A ) data. The results of IR, ESR and XRD indicate that the hydroxy group in the octahedral layer is attacked by crosslinking agent. Thus the silicon oxide pillars become directly linked via oxygen to the nickel atoms in the octahedral layer. The change of the ratio of Lewis to Bronsted acidity on Si-Ni-SMM reduced at 400℃ by H2 shows that the hydrogenating component such as Ni in the framework of SMM plays an important role in catalyst deactivation in H, atmosphere. This kind of action may be due to spilled- over hydrogen.展开更多
The orientation of HDTMA+ in the interlayer of organic pillared montmorillonites prepared at different concentrations of HDTMA+ have been studied using X-ray powder diffraction (XRD) and theoretical calculation. A ser...The orientation of HDTMA+ in the interlayer of organic pillared montmorillonites prepared at different concentrations of HDTMA+ have been studied using X-ray powder diffraction (XRD) and theoretical calculation. A series of arrangement models of HDTMA+ in the interlayer of montmorillonite have been proposed as lateral-monolayer (LM), lateral-bilayer (LB), pseudotrilayer (PT), paraf-fin-type-monolayer (PM), paraffin-type-bilayer (PB). With the increase of the concentration of HDTMA+, the arrange-ment model of HDTMA+ in the interlayer of montmorillo-nites changes as lateral-monolayer→lateral-bilayer→para- ffin-type monolayer→pseudotrilayer→paraffin-type-bilayer and the packing density of HDTMA+ in the interlayer in-creases gradually. In the intermediate stages, different mod-els may coexist.展开更多
Remove of titanium (Ti) from titanium-pillared montmorillont (TIPM) is not expected during its application as adsorbent and photocatalyst, etc. But studies on immobilization of Ti on TIPM are seldom reported. In t...Remove of titanium (Ti) from titanium-pillared montmorillont (TIPM) is not expected during its application as adsorbent and photocatalyst, etc. But studies on immobilization of Ti on TIPM are seldom reported. In this work, TIPM was synthesized from TIC14 and Na+-montmorillont (Na+-MMT). Then the prepared TIPM was heated at different temperatures (100, 240 and 450 ~C) to yield three TIPM samples (TIPM1, TIPM2, and TIPM3). Inductively coupled plasma optical emission spectrometer (ICP-OES) was used to determine the effect of heating temperature on the remaining amount of Ti on TIPMs. A two-step treatment method which is often used in the pretreatment and application of TIPM was developed to investigate the immobile character of Ti on TIPMs. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), N2 adsorption/desorption isotherm, thermogra- vimetric analysis and differential scanning calorimetry (TG-DSC) were also used to characterize TIPMs before and after the treatment. The results show that with an increase in heating temperature, the amount of Ti species re- mained on T1PM decreases gradually and Ti immobilization is strengthened on TIPM. For TIPM3, less than 2% Ti is removed from TIPM3 after the treatment required to simulate the practical conditions of TIPM in its application, while those of TIPM1 and TIPM2 are 6.6% and 8.4%, respectively. The reason may be that when TIPM is heated, Ti species intercalated into MMT become chemically bonded with the framework of MMT and partially migrate into the layer structure, which make Ti immobile on TIPM firmly during the treatment process.展开更多
Al-pillared mesoporous montmorillonite was facilely synthesized from concentrated Al13 solution obtained by vacuum concentrating-ultrasonic pillaring strategy.Concentrated Al13 solution could reduce the process of pil...Al-pillared mesoporous montmorillonite was facilely synthesized from concentrated Al13 solution obtained by vacuum concentrating-ultrasonic pillaring strategy.Concentrated Al13 solution could reduce the process of pillare and increase pillaring efficiency.The absolute value of layer distance could be increased by 0.96 nm via concentrated Al13 solution pillare.27Al NMR indicates that Al Keggin ions of concentrated Al13 are arranged in a more regular way by vacuum concentrating method.The Al-pillared mesoporous montmorillonite from concentrated Al13 solution has bigger specific surface area and even pore size distribution which were characterized by X-ray diffraction(XRD) and nitrogen adsorption measurement.Furthermore the catalytic activity of Ai-pillared montmorillonite loaded Ni and Mo catalysts was tested by the hydrodesulfurization of thiophene.The thiophene conversion reached 77.5%,which was higher than the corresponding value reported in the literature.展开更多
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℃.
基金Project (No. 000623) supported by the Provincial Natural Science Foundation of Guangdong, China.
文摘Both inorganic and organic pillared montmorillonites were used to adsorb phenol. Batch kinetics and isotherm studies were carried out to evaluate the effect of equilibrium time and pH on adsorption of phe- nol by montmorillonites and re-adsorbing characteristics of pillared montmorillonites. The adsorption of phenol increased with increasing solution pH values. The elimination ratio of phenol from the solution by the absorption of organic modified pillared montmorillonite (OrPMt) reached equilibrium quickly after vibrating for 5 minutes. Meanwhile for organic montmorillonite (OrMt), pillared montmorillonite (PMt) and montmorillonite (Mt), the time to reach phenol-absorption equilibrium were 20, 30 and 90 minutes, respectively. The adsorbing capacity of the pillared montmorillonite modified with surfactant improved greatly. The phenol-adsorbing capacity of pillared molltmorillonites mainly depended on microporous structure and surface component of the modified clays. After calcination at 500 ℃, the pillar structure and the basal spacing (1.83 um) were still stable. So the pillared montmorillonite could be recycled, and it was a potential material for adsorbing environmental pollutants.
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.
基金supported by the National Natural Science Foundation of China(29706011)Zhejiang Provincial Natural Science Foundation NSF(201057)is acknowledged
文摘A mesoporous titanium/silicon -containing montmorillonite-based catalytic materials has been synthesized by novel gallery-templated techniques. XRD, SEM, framework IR, and N2 adsorptiondesorption isotherms provided evidence of the formation of Si/Ti pillars. The synthetic materials show potential catalytic application for hydroxylation of phenol with peroxide.
文摘A novel bisupported bimetal catalyst PVP-PdCl2-FeSO4/Al-Mont-PEG600 was prepared by immobilization of PVP (poly (N-vinyl-2-pyrrolidone)) supported bimetallic catalyst using alumina pillared inartificial montmorillonite as the carrier. This catalyst has good dehalogenation activity and selectivity to aryl halides o-chlorotoluene in aqueous system in the presence of phase transfer catalyst (PEG) and sodium formate as hydrogen source. The catalyst also shows good reusability.
文摘Nickel-substituted mica-montmorillonite clays(Ni-SMM) were synthesized, the pillared clays, Si-Ni-SMM, were prepared from the Ni-SMM intercalated with NH2(C3H5)Si(OC2H5)3.The pillar perhaps consists of tripolymer of silica according to the judgement from the pillar height (8. 5A ) data. The results of IR, ESR and XRD indicate that the hydroxy group in the octahedral layer is attacked by crosslinking agent. Thus the silicon oxide pillars become directly linked via oxygen to the nickel atoms in the octahedral layer. The change of the ratio of Lewis to Bronsted acidity on Si-Ni-SMM reduced at 400℃ by H2 shows that the hydrogenating component such as Ni in the framework of SMM plays an important role in catalyst deactivation in H, atmosphere. This kind of action may be due to spilled- over hydrogen.
基金supported by the National Natural Science Foundation of China(Grant No.49972018)the Natural Science Foundation of Guangdong Province(Grant No.990522).
文摘The orientation of HDTMA+ in the interlayer of organic pillared montmorillonites prepared at different concentrations of HDTMA+ have been studied using X-ray powder diffraction (XRD) and theoretical calculation. A series of arrangement models of HDTMA+ in the interlayer of montmorillonite have been proposed as lateral-monolayer (LM), lateral-bilayer (LB), pseudotrilayer (PT), paraf-fin-type-monolayer (PM), paraffin-type-bilayer (PB). With the increase of the concentration of HDTMA+, the arrange-ment model of HDTMA+ in the interlayer of montmorillo-nites changes as lateral-monolayer→lateral-bilayer→para- ffin-type monolayer→pseudotrilayer→paraffin-type-bilayer and the packing density of HDTMA+ in the interlayer in-creases gradually. In the intermediate stages, different mod-els may coexist.
文摘Remove of titanium (Ti) from titanium-pillared montmorillont (TIPM) is not expected during its application as adsorbent and photocatalyst, etc. But studies on immobilization of Ti on TIPM are seldom reported. In this work, TIPM was synthesized from TIC14 and Na+-montmorillont (Na+-MMT). Then the prepared TIPM was heated at different temperatures (100, 240 and 450 ~C) to yield three TIPM samples (TIPM1, TIPM2, and TIPM3). Inductively coupled plasma optical emission spectrometer (ICP-OES) was used to determine the effect of heating temperature on the remaining amount of Ti on TIPMs. A two-step treatment method which is often used in the pretreatment and application of TIPM was developed to investigate the immobile character of Ti on TIPMs. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), N2 adsorption/desorption isotherm, thermogra- vimetric analysis and differential scanning calorimetry (TG-DSC) were also used to characterize TIPMs before and after the treatment. The results show that with an increase in heating temperature, the amount of Ti species re- mained on T1PM decreases gradually and Ti immobilization is strengthened on TIPM. For TIPM3, less than 2% Ti is removed from TIPM3 after the treatment required to simulate the practical conditions of TIPM in its application, while those of TIPM1 and TIPM2 are 6.6% and 8.4%, respectively. The reason may be that when TIPM is heated, Ti species intercalated into MMT become chemically bonded with the framework of MMT and partially migrate into the layer structure, which make Ti immobile on TIPM firmly during the treatment process.
文摘Al-pillared mesoporous montmorillonite was facilely synthesized from concentrated Al13 solution obtained by vacuum concentrating-ultrasonic pillaring strategy.Concentrated Al13 solution could reduce the process of pillare and increase pillaring efficiency.The absolute value of layer distance could be increased by 0.96 nm via concentrated Al13 solution pillare.27Al NMR indicates that Al Keggin ions of concentrated Al13 are arranged in a more regular way by vacuum concentrating method.The Al-pillared mesoporous montmorillonite from concentrated Al13 solution has bigger specific surface area and even pore size distribution which were characterized by X-ray diffraction(XRD) and nitrogen adsorption measurement.Furthermore the catalytic activity of Ai-pillared montmorillonite loaded Ni and Mo catalysts was tested by the hydrodesulfurization of thiophene.The thiophene conversion reached 77.5%,which was higher than the corresponding value reported in the literature.