A serial of ordered meso-macroporous phosphotungstic acid(HPW) supported on SiO2 nanocomposites were successfully prepared by a homogeneous precipitation method, using monodispersed polystyrene(PS) microspheres and ca...A serial of ordered meso-macroporous phosphotungstic acid(HPW) supported on SiO2 nanocomposites were successfully prepared by a homogeneous precipitation method, using monodispersed polystyrene(PS) microspheres and cationic surfactant as structure directing agent. These nanocomposites were used as catalysts for oxidative desulfurization(ODS) of model fuel. The materials were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), N2 adsorption-desorption isothrem, X-ray diffraction(XRD), and Fourier transform infrared spectra(FTIR). The characterization results suggested that the as-prepared material possessed ordered meso-macroporous architectures with Keggin type phosphotungstic acid dispersed homogeneously in SiO2 matrix. Under the selected reaction conditions, dibenzothiophene(DBT) in model fuel can be removed within 2 h at room temperature(30 ℃). In addition, only 1.2% of efficiency lose than the fresh catalyst even after 5 cycles.展开更多
A series of heteropoly acid (HPA) based Al2O3 catalysts with three-dimensional ordered (3DOM) structure were synthesized by colloidal crystal template method.Interconnected macropores (250 nm) could be clearly observe...A series of heteropoly acid (HPA) based Al2O3 catalysts with three-dimensional ordered (3DOM) structure were synthesized by colloidal crystal template method.Interconnected macropores (250 nm) could be clearly observed by scanning electron microscope (SEM) and transmission electron microscope (TEM).Mesopores could be detected by N2 adsorption-desorption isotherms which further confirmed the 3DOM structural characteristics of catalyst.Moreover,Keggin-type HPW was highly dispersed in the Al2O3 framework,which suggested by powder X-ray diffraction (XRD) and Fourier transform infrared spectra (FT-IR) results.The oxidation desulfurization (ODS) performance of 3DOM H3PW12O40/Al2O3 of refractory sulphur compounds was evaluated in the presence of hydrogen peroxide.It oxidized 98.5% of dibenzothiophene (DBT) into corresponding sulfone within 3 h,which exhibited superior ODS performance than corresponding mesoporous and microporous H3PW12O40/Al2O3 catalyst.The enhancement of ODS efficiency is related to the improvement of mass transfer of DBT in the pore channel resulting from the interconnected 3DOM structure.Furthermore,the as-prepared catalyst still demonstrates outstanding cycle performance after 6 runs,which could be easily recovered from the model fuel.展开更多
The synthesis, properties and dispersion mechanism of sulphonated acetone-formaldehyde superplasticizer （SAF） were presented. This superplasticizer was synthesized by the reaction among acetone, formaldehyde, sodium...The synthesis, properties and dispersion mechanism of sulphonated acetone-formaldehyde superplasticizer （SAF） were presented. This superplasticizer was synthesized by the reaction among acetone, formaldehyde, sodium sulfite and pyrosulfite. The structure and property were respectively characterized by IR and surface tension measurement. Performance of SAF in cement was evaluated by paste flow as well as heat calorimetry. The dispersion mechanism was identified via adsorption and zeta potential measurement. The results show that cement paste mixed with SAF shows good fluidity. SAF exerts little retarding effect on cement paste and it behaves like a typical polycondensate superplasticizer. The main dispersion mechanism of SAF is attributed to electrostatic repulsion.展开更多
In order to reduce the emission of SO_x in the environment,sulfur compounds must be removed efficiently from fuels.Three-dimensional highly ordered meso-macroporous HPW/TiO_(2)(3DO m/M HPW/TiO_(2))materials were synth...In order to reduce the emission of SO_x in the environment,sulfur compounds must be removed efficiently from fuels.Three-dimensional highly ordered meso-macroporous HPW/TiO_(2)(3DO m/M HPW/TiO_(2))materials were synthesized successfully by sol-gel method and applied as oxidative desulfurization catalyst for the model fuel.The characterization results displayed the existence of highly ordered meso-macroporous structures and the Keggin type of HPW was highly dispersed in TiO_(2)framework.The effect of catalyst on desulfurization under different reaction conditions was studied systematically.The results showed that the catalyst exhibited excellent desulfurization performance in the hydrogen peroxide oxidation system,which could be explained by the unique meso-macroporous structure of catalyst.In addition,the catalyst showed good cycling performance and the removal rate of DBT still reached 96.1%even after 6 cycles,providing a feasible method for the development and application of fuel deep desulfurization catalysts.展开更多
基金Supported by the National Nature Science Foundation of China(No.21476177)
文摘A serial of ordered meso-macroporous phosphotungstic acid(HPW) supported on SiO2 nanocomposites were successfully prepared by a homogeneous precipitation method, using monodispersed polystyrene(PS) microspheres and cationic surfactant as structure directing agent. These nanocomposites were used as catalysts for oxidative desulfurization(ODS) of model fuel. The materials were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), N2 adsorption-desorption isothrem, X-ray diffraction(XRD), and Fourier transform infrared spectra(FTIR). The characterization results suggested that the as-prepared material possessed ordered meso-macroporous architectures with Keggin type phosphotungstic acid dispersed homogeneously in SiO2 matrix. Under the selected reaction conditions, dibenzothiophene(DBT) in model fuel can be removed within 2 h at room temperature(30 ℃). In addition, only 1.2% of efficiency lose than the fresh catalyst even after 5 cycles.
基金Funded by the National Natural Science Foundation of China(No.21476177)。
文摘A series of heteropoly acid (HPA) based Al2O3 catalysts with three-dimensional ordered (3DOM) structure were synthesized by colloidal crystal template method.Interconnected macropores (250 nm) could be clearly observed by scanning electron microscope (SEM) and transmission electron microscope (TEM).Mesopores could be detected by N2 adsorption-desorption isotherms which further confirmed the 3DOM structural characteristics of catalyst.Moreover,Keggin-type HPW was highly dispersed in the Al2O3 framework,which suggested by powder X-ray diffraction (XRD) and Fourier transform infrared spectra (FT-IR) results.The oxidation desulfurization (ODS) performance of 3DOM H3PW12O40/Al2O3 of refractory sulphur compounds was evaluated in the presence of hydrogen peroxide.It oxidized 98.5% of dibenzothiophene (DBT) into corresponding sulfone within 3 h,which exhibited superior ODS performance than corresponding mesoporous and microporous H3PW12O40/Al2O3 catalyst.The enhancement of ODS efficiency is related to the improvement of mass transfer of DBT in the pore channel resulting from the interconnected 3DOM structure.Furthermore,the as-prepared catalyst still demonstrates outstanding cycle performance after 6 runs,which could be easily recovered from the model fuel.
基金Funded by the Western Region Traffic Construction Technology Program of the Ministry of Communications of China(No.2007319811130)
文摘The synthesis, properties and dispersion mechanism of sulphonated acetone-formaldehyde superplasticizer （SAF） were presented. This superplasticizer was synthesized by the reaction among acetone, formaldehyde, sodium sulfite and pyrosulfite. The structure and property were respectively characterized by IR and surface tension measurement. Performance of SAF in cement was evaluated by paste flow as well as heat calorimetry. The dispersion mechanism was identified via adsorption and zeta potential measurement. The results show that cement paste mixed with SAF shows good fluidity. SAF exerts little retarding effect on cement paste and it behaves like a typical polycondensate superplasticizer. The main dispersion mechanism of SAF is attributed to electrostatic repulsion.
基金Funded by the National Nature Science Foundation of China(No.21476177)。
文摘In order to reduce the emission of SO_x in the environment,sulfur compounds must be removed efficiently from fuels.Three-dimensional highly ordered meso-macroporous HPW/TiO_(2)(3DO m/M HPW/TiO_(2))materials were synthesized successfully by sol-gel method and applied as oxidative desulfurization catalyst for the model fuel.The characterization results displayed the existence of highly ordered meso-macroporous structures and the Keggin type of HPW was highly dispersed in TiO_(2)framework.The effect of catalyst on desulfurization under different reaction conditions was studied systematically.The results showed that the catalyst exhibited excellent desulfurization performance in the hydrogen peroxide oxidation system,which could be explained by the unique meso-macroporous structure of catalyst.In addition,the catalyst showed good cycling performance and the removal rate of DBT still reached 96.1%even after 6 cycles,providing a feasible method for the development and application of fuel deep desulfurization catalysts.
