La-SO42-/SBA-15 was synthesized with various amounts of lanthanum via incipient-wetness impregnation. Characterization was done by X-ray diffraction（XRD）, transmission electron micrographs（TEM）, nitrogen adsorptio...La-SO42-/SBA-15 was synthesized with various amounts of lanthanum via incipient-wetness impregnation. Characterization was done by X-ray diffraction（XRD）, transmission electron micrographs（TEM）, nitrogen adsorption, FTIR spectroscopic analysis, thermogravimetric analysis, and the total amount of acidity of catalyst was estimated by TPD of NH3. The results indicate that lanthanum has been incorporated into SBA-15 molecular sieve. The prepared materials（La-SO42-/SBA-15） keep the highly ordered mesoporous two-dimensional hexagonal structure and do not change the mesoporous channel structure of the support SBA-15. The catalyst showed best catalytic activity in the synthesis of n-butyl acetate. The optimum conditions of the esterification by orthogonal experiments were studied： the molar ratio of n-butanol to acetic acid 1：1.2, the amount of catalyst 7.5%, reaction time 80 min. The yield of n-butyl acetate could reach 93.2% under the optimum conditions. The catalyst was recyclable, cost effective and environmental friendly.展开更多
A mesoporous Al-Mg composite oxide with a hexagonal structure was synthesized with aluminium nitrate and magnesium nitrate as the reagents and sodium dodecyl sulfate（SDS） as the template in the presence of ethylened...A mesoporous Al-Mg composite oxide with a hexagonal structure was synthesized with aluminium nitrate and magnesium nitrate as the reagents and sodium dodecyl sulfate（SDS） as the template in the presence of ethylenediamine. The XRD, nitrogen adsorption-desorption and TEM studies indicate that the composite has a hexagonal framework structure and an average pore diameter of 2. 6 nm. The TG/DTA spectra indicate that the decomposition and the removal of the occluded surfactant of the sample take place in a range of 230-550 ℃. The mesoporous Al-Mg composite oxide exhibites a highly catalytic activity for the oxyethylation of fatty alcohols. Narrow-range distributed ethoxylates are formed in the presence of the mesoporous Al-Mg composite oxide catalyst. The distribution selectivity coefficient（Cx） is 24 when the mesoporous Al-Mg composite oxide was used as a catalyst for the oxyethylation of octanol and the average adduct degree of ethoxylates is 6. 4.展开更多
Co3O4-Ce O2 nanoparticles with increasing Co/Ce atomic ratio were prepared by wet impregnation and characterized by means of X-ray photoelectron. Co3O4 is prevalent in the samples with lower cobalt content, whereas Co...Co3O4-Ce O2 nanoparticles with increasing Co/Ce atomic ratio were prepared by wet impregnation and characterized by means of X-ray photoelectron. Co3O4 is prevalent in the samples with lower cobalt content, whereas Co3O4 is the main presence at high Co/Ce atomic ratios.Ce O2 is slightly reduced: Ce(III) is evident at the interface supported/ supporting oxide.X-ray diffraction and scanning electron microscopy allowed us to obtain interesting information concerning particle dimensions and growing morphology. New acidic/basic sites are evident on the surface of the nanocomposites; this is particularly evident in the samples with lower cobalt content.展开更多
基金the Graduate Student Innovation Scientific Research Projects of Heilongjiang Province, China (No.YJSCX2007-0282-HLJ)
文摘La-SO42-/SBA-15 was synthesized with various amounts of lanthanum via incipient-wetness impregnation. Characterization was done by X-ray diffraction（XRD）, transmission electron micrographs（TEM）, nitrogen adsorption, FTIR spectroscopic analysis, thermogravimetric analysis, and the total amount of acidity of catalyst was estimated by TPD of NH3. The results indicate that lanthanum has been incorporated into SBA-15 molecular sieve. The prepared materials（La-SO42-/SBA-15） keep the highly ordered mesoporous two-dimensional hexagonal structure and do not change the mesoporous channel structure of the support SBA-15. The catalyst showed best catalytic activity in the synthesis of n-butyl acetate. The optimum conditions of the esterification by orthogonal experiments were studied： the molar ratio of n-butanol to acetic acid 1：1.2, the amount of catalyst 7.5%, reaction time 80 min. The yield of n-butyl acetate could reach 93.2% under the optimum conditions. The catalyst was recyclable, cost effective and environmental friendly.
基金Supported by the Natural Science Foundation of Heilongjiang Province(No.9810B).
文摘A mesoporous Al-Mg composite oxide with a hexagonal structure was synthesized with aluminium nitrate and magnesium nitrate as the reagents and sodium dodecyl sulfate（SDS） as the template in the presence of ethylenediamine. The XRD, nitrogen adsorption-desorption and TEM studies indicate that the composite has a hexagonal framework structure and an average pore diameter of 2. 6 nm. The TG/DTA spectra indicate that the decomposition and the removal of the occluded surfactant of the sample take place in a range of 230-550 ℃. The mesoporous Al-Mg composite oxide exhibites a highly catalytic activity for the oxyethylation of fatty alcohols. Narrow-range distributed ethoxylates are formed in the presence of the mesoporous Al-Mg composite oxide catalyst. The distribution selectivity coefficient（Cx） is 24 when the mesoporous Al-Mg composite oxide was used as a catalyst for the oxyethylation of octanol and the average adduct degree of ethoxylates is 6. 4.
基金support of this research by the Key Projects of the Natural Science Foundation of Heilongjiang Province (No. B201010)
文摘Co3O4-Ce O2 nanoparticles with increasing Co/Ce atomic ratio were prepared by wet impregnation and characterized by means of X-ray photoelectron. Co3O4 is prevalent in the samples with lower cobalt content, whereas Co3O4 is the main presence at high Co/Ce atomic ratios.Ce O2 is slightly reduced: Ce(III) is evident at the interface supported/ supporting oxide.X-ray diffraction and scanning electron microscopy allowed us to obtain interesting information concerning particle dimensions and growing morphology. New acidic/basic sites are evident on the surface of the nanocomposites; this is particularly evident in the samples with lower cobalt content.
