SBA-15 silica-supported potassium catalysts were first reported for the selective oxidation of ethane to aldehydes by using oxygen as oxidant. It was found that SBA-15-supported potassium catalysts exhibited very high yield of aldehydes, especially surprisingly high yield of acrolein in the selective oxidation of ethane. The SBA-15-supported catalyst with 2% loading of potassium showed the best performance for the partial oxidation of ethane to aldehydes. The yields highest of acrolein and total aldehydes (formaldehyde, acetaldehyde, and acrolein) were 2.5% and 5.2%, respectively, when the ethane conversion was 14.8% at the reaction temperature of 748 K.

Vanadium oxides supported on γ-Al2O3, SiO2, TiO2, and ZrO2 were studied on their molecular structures and reactive performances for soot combustion. To investigate the effect of different alkali metals on the structures and reactivities of supported-vanadium oxide catalysts, they were doped into the V4/TiO2 catalyst which had the best intrinsic activity for soot combustion in the selected supported vanadium oxide catalysts. The experimental results demonstrated that the catalytic properties of these catalysts depended on the vanadium loading amount, support nature, and the presence or the absence of alkali metals. The spectroscopic analysis (FT-IR and UV–vis) and H2-TPR results revealed that the higher activity of alkali-promoted vanadium oxide catalysts could be related to the ability of alkali metal promoting the redox cycle of the active vanadyl species. TG results showed that adding alkali to Vm/TiO2 catalyst was beneficial to lowering their melting points. Low melting points could ensure the good surface atom migration ability, which would improve the contact between the catalyst and soot. Due to the alkali metal components promoting the redox ability and the mobility of the catalysts, alkali-modified vanadium oxide catalysts could remarkably improve their catalytic activities for soot combustion. The catalytic activity order for soot combustion followed Li > Na > K > Rb > Cs in the catalyst system of alkali-V4/TiO2, and the reason why it followed this sequence was discussed.

The redox and acid–base characters of silica-supported vanadium or alkali-modified vanadium catalysts by varying vanadium loading were studied with the methods of H2-TPR, NH3-TPD and CO2-TPD combining other structural characterization techniques of ESR, UV–vis spectroscopy. The effects of these properties on their catalytic performances for the ethane oxidation by oxygen were investigated. For both the unpromoted V/SiO2 (V:Si = x:Si) and promoted Cs–V/SiO2 (Cs:V:Si = 1:x:100) systems, the reduction extent and the reducibility increase with increasing vanadia loading and the presence of cesium enhances the reduction extent. The structures of the vanadyl species have large effect on the vanadia reducibility and the isolated surface vanadyl species are less reducible than the polymeric vanadyl species including microcrystalline vanadia. For the samples with high vanadia loading (≥2.0%), the reducibility is high and thus the redox characteristic of the catalyst is one of the most important factors that govern the catalytic reactivity. In the samples with low vanadia loading (<0.5%), the reducibility is low. Therefore, the basicity or acidity characteristics of the catalyst become the major factors that control the catalytic reactivity. The cesium promoted samples Cs–V/SiO2 (2.0 and 10.0%) exhibit high reducibilities, which qualitatively suggests that their oxygen mobility is very high and may result in deep oxidation of ethane. In contrast, those samples with low reducibility are selective for the oxidation of ethane including ODH to ethylene and oxygenate formation.

A series of nanopowder Ce–Zr–Pr oxide catalysts were synthesized by a new method which was a low temperature synthesis approach combining rotating evaporation and auto-combustion techniques. The catalysts were characterized by means of XRD, Raman, and SEM. The results showed that the synthesized catalysts had a cubic fluorite structure, nanoparticle sizes and good catalytic activity for soot oxidation.

A new method for the synthesis of Ni–Mo bimetallic nitrides was reported in the present paper. The bimetallic nitrides were successfully prepared by a temperature-programmed reaction between bimetallic oxide precursors and the mixed gases of N2 and H2 instead of NH3. By adjusting pH values of the solution in the process of co-precipitation, pure NiMoO4 or NiMoO4 with excess MoO3 was obtained, and then pure Ni3Mo3N or Ni3Mo3N with γ-Mo2N was synthesized by nitriding the precursors. The structural properties of the precursors and their corresponding nitrides were investigated by means of X-ray diffraction (XRD), ultraviolet laser Raman spectroscopy, thermogravimetric (TG) analysis and chemical analysis of total nitrogen content.