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The combined catalysts Mn/Ba/Al2O3-Pt/Ba/Al2O3and Mn/Ba/Al2O3+Pt/Ba/Al2O3for NOxstorage-reduction were investigated. Mn/Ba/Al2O3indicated high activity of NO oxidation and NOxstorage in the oxidation-storage reaction and certain reduction activity in the storage-reduction reaction. The combination of Pt/Ba/Al2O3with Mn/Ba/Al2O3could enhance the activity of NOxstorage-reduction under dynamic lean-rich burn conditions. Compared to Pt/Ba/Al2O3catalyst, although the Pt content decreased half over Mn/Ba/Al2O3-Pt/Ba/Al2O3and Mn/Ba/Al2O3+Pt/Ba/Al2O3, the NOxconversion increased 9.4% and 6.3% at 350 °C. The pollutions such as NOxand CO could be eliminated effectively over two combined catalysts with low Pt content under dynamic lean-rich burn conditions.

NiMgAlO catalysts were prepared by two methods: coprecipition and impregnation. They were used to simultaneously adsorb SO2 and NO with O2 in a fixed bed at atmospheric pressure. Typically the molar composition of the feed gas was 1% SO2, 0.2% NO and O2 with ultra-high purity Ar as the diluent. The results showed the catalysts were excellent materials for the simultaneous oxidation adsorption of SO2 and NOx. The two kinds of catalysts were compared for the SO2 and NOx adsorption capacity. The NiMgAlO catalyst prepared by coprecipition had better adsorption than impregnation. When NiMgAlO catalysts with 10 wt-% Ni content were calcined at 550°C, adsorption capacity was the largest at 120°C adsorption temperature: 1.392 mmol SO2 and 0.213 mmol NOx were adsorbed on 1 g catalyst prepared by the coprecipition method. The causes are seen by the XRD, surface area and porous size analysis.

The solid state reaction method, coprecipitation method and citric acid method were employed for the preparation of Cr-Mn mixed-oxide catalysts. Experimental results showed that this catalytic system has good selective catalytic reduction (SCR) properties of NOxby ammonia in the presence of excess oxygen at low temperature (80-220°C). 97.8% conversion of NOxwith 100% selectivity of N2had been achieved on Cr-MnOxmixed oxide prepared by the citric acid method at 120°C with the space velocity of 30,000 h-1. X-ray diffraction, BET were adopted for the characterization of the active phase. The characterization results showed that a new crystal phase CrMn1.5O4generated in mixed oxides which was the active center of the Cr-Mn catalysts.

Low amount of manganese meso-tetraphenyl porphyrin [Mn(TPP)] was used for highly efficient selective oxidation of sulfide to sulfone by hydrogen peroxide at room temperature. Sulfones were produced directly with yields generally around 90% while the catalyst concentration was only 4×10−5 mol·L−1. In a large-scale experiment of thioanisole oxidation, the isolated yield of sulfone (87%) was obtained and the turnover number (TON) reached up to 8×106, which is the highest TON for the oxidation systems of sulfide to sulfone catalyzed by metalloporphyrins.

Efficient selective oxidation of alcohols to carbonyl compounds by molecular oxygen with isobutyraldehyde as oxygen acceptor in the presence of metalloporphyrins has been reported. Ruthenium (III) meso-tetraphenylporphyrin chloride (Ru(TPP)Cl) showed excellent activity and selectivity for oxidation of various alcohols under mild conditions. Moreover, different factors influencing alcohols oxidation, for example, catalyst, solvent, temperature, and oxidant, have been investigated. In large-scale oxidation of benzyl alcohol, the isolated yield of benzaldehyde of 89% was observed.

A reusable solid catalyst, MnFe1.8Cu0.15Ru0.05O4, has been developed as an effective catalyst for the aerobic oxidation of sulfides and sulfoxides to sulfones. The ruthenium modified spinel catalyst is the first example reported for such reaction under mild condition with molecular oxygen as the only oxidant. The oxidation reaction proceeded via an electrophilic attack of the oxygen atom of the catalyst on the electron-rich sulfur atom of the substrate.

A facile, substrate-selective and transition metal-free oxidation of benzylic and allylic alcohols catalyzed by β-cyclodextrin with NaOCl oxidant using water as an only solvent was developed.

A novel, facile, and environmentally-friendly process for fabrication of NiO2 was developed and used as both a stoichiometric oxidant and an effective catalyst for benzyl alcohol oxidation. That simultaneous stoichiometric and catalytic reactions might exist in many reactions is proposed.

Efficient selective oxidation of alcohols to carbonyl compounds by molecular oxygen with isobutyraldehyde as oxygen acceptor in the presence of metalloporphyrins has been reported. Ruthenium (III) meso-tetraphenylporphyrin chloride (Ru(TPP)Cl) showed excellent activity and selectivity for oxidation of various alcohols under mild conditions. Moreover, different factors influencing alcohols oxidation, for example, catalyst, solvent, temperature, and oxidant, have been investigated. In large-scale oxidation of benzyl alcohol, the isolated yield of benzaldehyde of 89% was observed.

Highly efficient selective oxidation of sulfides to sulfoxides by molecular oxygen catalyzed by ruthenium (III) meso-tetraphenylporphyrin chloride (Ru(TPP)Cl) with isobutyraldehyde as oxygen acceptor has been reported. In large-scale experiment of thioanisole oxidation, the isolated yield of sulfoxide of 92% was obtained and the turnover number reached up to 92,000.

The prepared Cu-ZSM-5 catalyst presents higher activity at low temperature during the selective catalytic reduction (SCR) of NO, and the conversion from NO to N2 is 70.6% at 613 K. The in situ diffuse reflectance FTIR spectroscopy (in situ DRIFTS) is an important method for studying surface adsorption of catalyst and mechanism of catalytic reaction, and was used to study the surface adsorbed species and the selective catalytic reduction reaction of NO on Cu-ZSM-5 catalyst in the presence of propene as reductant, with excess O2 and at 298-773 K. Based on the in-situ DRIFTS, a reaction mechanism is proposed that on Cu-ZSM-5, NO is first transformed to a series of NO(x) surface adsorbates, then these species react with the activating species of propene (C(x)H(y) or C(x)H(y)O(x)) to form organo-intermediates, including a process from organo-NH to organo-CN again to organo-NO(x) (organo-nitro or organo-nitrito), and finally these key intermediates react to form nitrogen. The role of Cu is to promote NO(x) content. Propene is easily activated on Cu-ZSM-5 with oxygen, and furthermore, the presence of oxygen is necessary to form organo-NO(x) intermediates.

The Stability of framework of titanium silicalite-1 (TS-1) was investigated by high temperature diffuse reflectance FT-IR spectroscopy (DRIFTS), and the results showed that the 960 cm(-1) peak belonging to Ti-framework was stabilized at 673 K, but the two peaks belonging to framework shifted to lower frequencies by about 13 cm(-1) at 673 K. The effect on the framework after H2O2 adsorption was discussed. The results showed that the 960 cm(-1) peak lowered and shifted to high frequencies by about 11 cm(-1), but it recovered with vacuum or heating up. It was suggested that the 960 cm(-1) peak characterizes Ti==O, and this explained why the 960 cm(-1) peak shifted to high frequencies well. TS-1 catalytic oxidization of styrene was investigated by in situ DRIFTS. The reaction process was detected and phenyl aldehyde was the main product. Based on in situ analysis, it was proposed that H2O2 was adsorbed on Ti in framework of TS-1 to form active center.

Highly efficient epoxidation of olefins by molecular oxygen with catalytic amount of manganese meso-tetraphenylporphyrin (Mn(TPP)) at the ppm level were reported. The catalyst conferred high activity and selectivity for the olefins epoxidation under ambient temperature and atmospheric pressure. The turnover number (TON) of the catalyst could reach up to 700 million, which is comparable to enzyme catalysis.

A facile, substrate-selective and transition metal-free oxidation of benzylic and allylic alcohols catalyzed by β-cyclodextrin with NaOCl oxidant using water as an only solvent was developed.

An in situ diffuse reflectance FTIR spectroscopy (DRIFTS) study of the selective catalytic reduction (SCR) of NO with propene in the presence of excess O2 was carried out over Ag/SAPO-34 catalyst. The SCR reaction was investigated at temperatures from 573 to 773 K, and the role of oxygen in the NO reduction process was determined by comparing experiments using an initial reaction mixture containing oxygen and without oxygen. The results show that both NO and propene are easily activated in oxygen. Furthermore, the presence of oxygen is necessary to form organo-NOx adsorbed species. Based on these experiments, a reaction mechanism is proposed that NO, propene and oxygen react to form organo-nitro and organo-nitrito adsorbed species as key intermediates, and then these intermediates decompose to nitrogen.

The adsorption of H2O, NH3 and NO in molecular sieve SAPO-34 was studied by in situ DRIFTS at temperatures from 298 K to 773 K. The results show that the phenomenon of adsorption is reversible for H2O, but not for NH3 and NO. The water in SAPO 34 is absolutely deadsorbed at 623 K and the bridged Si-OH-Al group is observed at 3,625-3,600 cm-1. It is found that SAPO-34 displays good adsorption-catalysis activity for NH3 and NO. After adsorbing NH3, the bridged hydroxyls disappear, but three peaks appear at 3,135, 3,032 and 1,399 cm-1 at 423 K, and reach their climax at 673 K. The height of the peaks are 3.9, 1.7 and 6.7 times as much as SAPO-34 framework peak's, respectively. A strong and sharp peak is also observed at 1,364 cm-1 after NO adsorption at room temperature, and it exhibit approximately the same intensity with the framework peak. Analysis of these peaks indicate that there could produce new species NO3-.