The mesoporous molecular sieve was synthesized by using silica from water glass of industry,titanium from TiCl3,H2SO4 for adjusting the pH of the slurry and CTMAB as template in an open-vessel.The mole ratio of the slurry mixture was: n(SiO2)∶n(Na2O)∶n(CTMAB)∶n(TiCl3)∶n(H2O)=7∶2.08∶1.4∶(0.07,0.14,0.28)∶530.The product was producted by making the mixed slurry crystallize at 373 K for 12 h and used as catalyst in catalytic oxidation of cyclohexene to epoxy cyclohexane.The characterization of its crystal order and framework titanium was carried out by means of X ray diffraction(XRD),Fourier transform infrared spectrometer(FT-IR),Visiblespectroscopy(UV-Vis) and mensuration of pore structure.The effects of titanium source concentration on the crystal parameter and catalytic oxidation activity of the mesoporous molecular sieve was discussed.The results showed that within the limits of discussed silicon titanium molar ratio(100~25),mesoporous molecular series Ti-MCM-41 with good Long-range order and crystallinity can be prepared in an open system.The framework symmetry,specific surface area,pore volume and pore diameter of Ti-MCM-41 reduces gradually along with increasing titanium source concentration and Ti content into the molecular sieve framework which leads to mesoporous silica skeleton tending to chaos,but its increasing activity isn't affected in catalytic oxidation of cyclohexene to epoxy cyclohexane.

The mesoporous molecular sieve was synthesized by using silica from water glass in industry,titanium from TiCl3,H2SO4 for adjusting the pH of the slurry and CTMAB as template in an open-vessel.The mole ratio of the slurry mixture was:n(SiO2)∶n(Na2O)∶n(CTMAB)∶n(TiCl3)∶n(H2O)=7∶2.08∶1.4∶0.14∶530.The product was prepared by making the mixed slurry crystallizing at 373 K for certain time and used as catalyst in catalytic oxidation of cyclohexene to epoxy cyclohexane.The characterization of its crystallinity and framework titanium was carried out by means of X-ray diffraction(XRD),fourier transform infrared spectrometer(FT-IR),visiblespectroscopy(UV-Vis) and mensuration of pore structure.The effect of crystallization time on the crystal parameter and catalytic oxidation activity of the mesoporous molecular sieve was discussed.The results showed that within the limits of discussed crystallization time(0.5-5 d),mesoporous molecular series Ti-MCM-41 with good long-range order and crystallinity could be prepared in an open system.The framework symmetry,specific surface area,pore volume and pore diameter of Ti-MCM-41 reduced gradually along with increasing crystallization time in range of 0.5-3 d and Ti content into the molecular sieve framework which leads to mesoporous silica skeleton tending to chaos,but its increasing activity wasn't affected in catalytic oxidation of cyclohexene to epoxy cyclohexane.After crystallizing for 3 d,titanium content no longer increased,and the pore structure of molecular sieve,conversion and selectivity of reaction almost no longer changed.

Supercritical carbon dioxide (SC CO2) was used as a carrier/solvent for the "dry" alumination of mesoporous silica to prepare aluminium-containing mesoporous MCM-41. The effect of alumination on the structure and crystallinity of the materials was studied. In addition, the hydrothermal and thermal stability of this material have been investigated and compared with Al-MCM-41 prepared via conventional impregnation and direct hydrothermal synthesis. Irrespective of the preparation method, the surface area, pore diameter, pore volume, and crystallinity of Al-MCM-41 all decrease after hydrothermal and thermal treatments. However, Al-MCM-41 materials prepared with the assistance of SC CO2 possess better hydrothermal and thermal stability. This method allows for the incorporation of aluminum onto rather than into pores wall, without disintegration of the mesoporous structure, compared to Al-MCM-41 that has been prepared via impregnation and direct hydrothermal synthesis.

TiO2/MCM-41 mesoporous molecular sieve materials have been prepared with the assistance of supercritical carbon dioxide (SC CO2). Effects of temperature and CO2 pressure have been studied.The materials were characterized by X-ray diffraction (XRD),N2 adsorption-desorption experiment,FT-IR,UV-Vis spectroscopy and scanning electronic microscope (SEM).The results suggest that the titanium species can be transported into the pores deeply in the SCCO2 -assisted grafting process. So this supplies the possibility that the incorporated titanium dioxide may become a thin layer onto the pore walls of MCM-41.

H2O and highly pure N2 was generated in the range of 100-300°C, when commercial nitrogen and hydrogen gas past through high temperature superconductor YBa2 Cu3 O7-x(YBCO). The results of XRD, TG analysis and the measurement for nitrogen purity indicated that YBCO might be a very useful oxidation catalyst in gas purification. The optimum temperature of catalysis is in the range of 130-150°C The oxidation catalysis mechanism of YBCO was discussed on the basis of the saturation isothermal of oxygen adsorption of YBCO and the Langmuir theory and so on.

Light paraffins will play an important role as feedstocks of chemical industry to substitute for oil in 21century,and the activation of C-H bonds of light paraffins is an attractive challenging research subject.This article summarizes the catalytic activation of the C-H bonds of light paraffins,especially methane,under mild liquid phase conditions.

The deposit carbon on Ni/ZrO_2 catalyst was studied when using methane partial oxidation to syngas in the YBCO membrane reactor.Results show that the velocity of the deposited carbon increases with the temperature.According to the equilibrium constant of the deposit carbon reaction,the deposited carbon reaction is mainly caused by the decomposed of methane.From SEM pictures the species of the carbon is mainly filiform carbon at the temperature between 850 ℃ and 875 ℃.When temperature rises to 900 ℃,the species of the carbon is mainly contained carbon,which affects the activity of the catalyst strongly.

以工业催化学科为例,讨论了通过设置专门课程促进研究生了解本学科前沿进展的必要性,并通过实践,对课程的实施情况与效果作了介绍和分析.

Porous alumina material was prepared with activated carbon as template and aluminum acetylacetonate as precursor in supercritical carbon dioxide (SC-CO2). The effects of coating temperature and pressure on the coating ratio in the supercritical CO2 were studied, and optimal coating conditions at 80℃and 22 MPa were explored. The X-ray diffraction (XRD) result shows that the product isα-Al2O3, the BET surface areas calculated from the nitrogen adsorption isotherms of the product is up to 67. 20 m /g and the average pore diameter is about 4 nm. SEM experimental results indicated the activated carbon template was well replicated by the porous product and TEM results showed the Al2O3 nanoparticles were well dispersed in the product.

We investigated the performance of YBa2Cu3O7−x (YBCO) membrane reactor in the process of partial oxidation of methane (POM) to syngas. When Ni/ZrO2 catalyst was used the CH4 conversion and CO selectivity could reach almost 100% and 95%, respectively, and the oxygen permeation fluxes could reach 1.5mlmin−1cm−2 at 900°C. The YBCO membranes reactor also showed self-catalytic properties; without any catalysts the CH4 conversion and CO selectivity could reach about 28% and 90% at 900°C, respectively. However, the stability of YBCO membrane was not desirable because of the reduction of copper from the YBCO membrane. The reaction mechanism of POM in YBCO reactor was also discussed based on the influence of space velocity (SV) on CO selectivity. The indirect partial oxidation mechanism may be the dominant mechanism of POM process in the YBCO membrane reactor.

The ZSM-5 zeolite was synthesized with inorganic amine plate.The data of Pulse catalytic isomirization of m-xylene on the HZSM-5 were measured in various temperatures and carrying gas flow rates.Experimental results showed that the main conversion process of m-xylene on the HZSM-5 zeolite was unimolecular transfer reaction appearing as a first order kinetic characterization in the reaction conditions of temperture range of 758~801 K,carrying gas flow rate and pressure in the region of 22~60 ml/min and 0.2~0.3 Mpa respectively.The apparent activation energy,the adsorption heat and the activation energy of surface reaction were 119.2 kJ/mol,47.2 kJ/mol and166.4 kJ/mol respectively.

The research progresses of methane partial oxidation to syngas using mixed conducting oxygen-permeable membrane reactor are introduced.The influences of the perovskite oxide structure on oxygen permeability and permeation stability,membrane stability in the reducing environment,membrane surface modification,as well as the potential applications of this method are reviewed.

The parameters to be controlled to coat metallic walls by VOx/TiO2 catalysts which are used in the mild oxidation of hydrocarbons and NOx abatement are studied. Stainless steel (316L) was chosen because of its large application in industrial catalytic reactors. TiO2 films on stainless steel were obtained by dip-coating in two steps. Superficially oxidized plates were first dipped in Ti-alkoxide sol–gel to be coated by a very thin layer of TiO2. On this anchoring layer was then deposited a porous film of titania by dipping plates in an aqueous suspension of TiO2 particles. After calcination, VOx species were grafted to TiO2/SS plates and their loading was determined by means of X-ray photoelectron spectroscopy. The chemical and mechanical resistances of films were controlled by several tests. Laser Raman spectroscopy, X-ray diffraction and scanning electron microscopy were used to characterize the samples after each step of preparation. The porous texture was determined using a thermobalance. The dispersion and the nature of VOx species and the value of theoretical monolayer of VOx on TiO2/stainless steel are shown to depend on the surface V/Ti ratio, in the same manner as for VOx/TiO2 coating anodised aluminum plates and as for VOx/TiO2 powders. Therefore, we have demonstrated that the shaping of TiO2 has no influence on the characteristics of the active phase, which is of prime importance for catalytic applications in structured reactors.

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A Al2O3/Fe2O3 mesoporous composite has been prepared with a nanoscale casting process using activated carbon as template in supercritical carbon dioxide (SC CO2). The composite precursor of iron(III) acetylacetonate (Fe(acac)3) and aluminum acetylacetonate (Al(acac)3) and acetone were dissolved in supercritical CO2 and then coated on activated carbon in the desired supercritical conditions. After removal of activated carbon template by calcination in air at 600 °C, a Al2O3/Fe2O3 mesoporous composite was obtained. Temperature, pressure, and composite precursor ratio effects were studied. X-ray diffraction pattern proved that the product was composed of α-Al2O3 and γ-Fe2O3. Dendritic nanocrystals were observed from TEM graphs. SEM results show that the porous structure of activated carbon template was well replicated by composite product. The product pore structure information was calculated from the nitrogen sorption isotherms.

Titania/silica mesoporous composites have been prepared with nanoscale casting process using activated carbon as template in supercritical carbon dioxide (SC CO2). The composite precursor of tetrabutyl titanate and tetraethyl orthosilicate (TEOS) were dissolved in supercritical CO2, and then coated on activated carbon in the desired supercritical condition. After removal of activated carbon template by calcinations in air at 600°C, TiO2/SiO2 mesoporous composite was obtained. The effects of CO2 pressure and temperature have been studied on the coating ratio during the supercritical condition. The products were characterized by XRD, nitrogen sorption isotherms, SEM and TEM. SEM result indicates that the composite product has pretty well porous structure and the product pore structure information had been calculated from the nitrogen sorption isotherms. The titanium dioxide was in anatase phase and the largest BET surface area is up to 318.70m2/g. TEM experimental result shows that in the composite product, some titania nano-wire was formed.

The coking and deactivation of virgin naphtha aromatization catalyst are studied on isothermal reactor. The impact of coking on catalyst physical properties, acidity and activity as well as the effect of reactor temperature and reaction time length on catalyst coking are investigated The results indicate that the catalyst pore volume,specific surface area and strong and weak acids are reduced in different degrees with incremental coking on catalyst, indicating that the coke on the catalyst has not only blocked the access pore paths but also covered the catalyst acidic site, which results in the catalyst deactivation. With extension of reaction time, the coking tends to be saturated and a little increase in coking will lead to a significant deterioration of catalyst performances. The increase of reaction temperature will accelerate the coking rate of catalyst.

Nanoporous ferric oxide has been prepared with nanoscale casting process using activated carbon template in supercritical carbon dioxide. The precursors with the cosolvent of acetone were dissolved in supercritical CO2, and then attached to activated carbon in the supercritical condition. After removal of the activated carbon template by calcinations in air at 873K, the nanoporous Fe2O3 was obtained. Four factors were considered to study the effect on the coating ratio and yield. The structure and morphology of the products were characterized through nitrogen adsorption–desorption isotherms, thermal gravimetric analysis (TGA), wide-angle X-ray diffraction (WAXD) and transmission electron microscopy (TEM).

Zirconium phosphate is a novel porous material with many functions developed in the recent years. Some mesoporous materials of zirconium phosphate were synthesized by hydrothermal method using some templates such as CTAB, TBAB, diethyl amine, ethylenediamine and urea, respectively. The specific surface area, pore radius and pore volume of these mesoporous materials were measured. The results showed that the specific surface area was in the range of 116.5-218.1 m 2/g, the pore radius in the range of 4.40-7.22 nm, the pore volume in the range of 0.26-0.72 ml/g, respectively. In addition, the effect of different templates was discussed on distribution of pore radius during the preparation of the mesoporous zirconium phosphate material by hydrothermal synthesis.