A comparative study on the effects of alkali metal on the structures, physico-chemical properties and catalytic behaviors of silica-supported vanadium catalysts for the selective oxidation of ethane and the complete oxidation of diesel soot was reported.

Fe-modified HZSM-5 catalysts were firstly used for catalytic cracking of isobutane, and the influence of Fe-loading on the catalytic performances of FeHZSM-5 catalysts for the cracking of isobutane was also investigated. The results indicated that both the isobutane cracking activity and the selectivity to light olefins of FeHZSM-5 samples with a small amount of Fe were greatly enhanced compared with the unpromoted HZSM-5, and very high yields of total olefins and propylene were obtained. For example, for the FeHZSM-5 sample loading with 0.010 mmol/g Fe the total yield of olefins reached 65.6%, and the yield of propylene was 32.4% at 625℃.

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.

Co3O4, NiCo2O4 and LaCo2O4 catalysts were synthesized by the citric acid-ligated method. These catalysts containing Co-oxide active components can largely lower the temperature of sool combustion under tight contact conditions. Under the conditions of loose contact NiCo2O4 cannot promote soot combustion, but LaCo2O4 can effectively promote soot combustion because the nanometric perovskite-type catalyst LaCoO3 produced in the LaCo2O4 sample.

It is reported that cyclic voltammetry (CV) is a strong tool to investigate catalytic reactions not only in homogeneous catalysis, but also in heterogeneous catalysis. The application of CV measurements in homogeneous catalysis is illustrated through investigation of NO removal (NO reduction and decomposition), which is an urgent task of today in environment catalysis. Results of our study indicate that both the area of redox peak and the symmetry of redox potentials of catalyst are important parameters in determining the catalytic activity, but each has his strong point in different reactions (NO reduction and decomposition). We suggest that CV is a powerful means to select catalysts for NOx removal.