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In this work, CuOx/mesoporous Hangjin 2# clay catalysts were synthesized from Cu(NO3)2 and Hangjin 2# clay in one step. The prepared catalysts were characterized by X-ray diffraction (XRD), N2 adsorption–desorption measurements, high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray analysis (EDX), and UV–visible diffuse reflectance spectroscopy (DRUV). These materials were employed in photocatalytic benzene hydroxylation to phenol with H2O2 as the oxidant, and the effects of the copper loading and light source on the reaction were studied. The results show that the phenol selectivity and yield initially increased and then decreased with increasing copper content. Under the optimized reaction conditions, the phenol selectivity and yield were 91.9 % and 25.6 %, respectively. Catalyst is still active after the repeat three times.

Catalyzed by supported palladium nanoparticles, a decarbonylative amidation reaction between various aryl esters and formamides by C–O bond activation has been developed for the synthesis of amides. The catalyst can be reused and shows high activity after five cycles. The XPS analysis of the catalyst before and after the reaction suggested that the reaction might be performed via a Pd0/PdII/PdIV catalytic cycle that began with Pd0. The hot filtration test strongly suggests that the present reaction would proceed in a heterogeneous manner.

Mesoporous NiO was prepared by the template synthesis method, using polyethylene glycol as a template, Ni(NO3)2·6H2O and Ni(CH3COO)2·4H2O as a nickel source. The major factors that influenced the formation of mesoporous NiO, such as nickel source, calcining temperature and molecular size of PEG, were estimated. As a result, the nickel source and calcination process could determine the crystallizability and organization of mesostructured NiO particles. The molecular size of PEG surfactant is not only relevant to the pore size of mesoporous NiO, but also of effect on the selectivity to propylene. The fine mesoporous NiO could be formed by using Ni(CH3COO)2·4H2O as nickel source and PEG400 as template, and then being calcined at 400–600 °C. The mesoporous NiO catalysts exhibit significant catalytic activities for the oxidative dehydrogenation of propane. The propylene yield of 14 % was obtained at propane conversion of 27 % at 350 °C. Furthermore, the selectivity to propylene can be maintained around 50 % even at 600 °C, indicating the high catalytic stabilities of mesoporous NiO catalysts in the present work. We proposed that a non-stoichiometric oxygen species on the surface is the catalytic active site and the mesoporous structure is the key factor for the high catalytic stabilities in the light of the characteristic results of mesoporous NiO catalysts.

SiO2 is generally regarded as an “inert” support of gold catalysts for CO oxidation. We find that silica obtained from a natural clay mineral can be used as excellent gold-support for efficient CO oxidation at relatively low temperature. Fine Au particles are found to locate around the Al sites, rather than on pure SiO2 area. Accordingly, high Au loading and catalytic activity for the clay-based SiO2 supports are ascribed to the residual aluminum originally from the clay.

Monolithic mesoporous carbons were prepared through a simple autoclaving method using citric acid as catalyst instead of HCl. The presence of citric acid plays an important role in determining the structural ordering of the resultant mesoporous structure due to the –COOH groups which can enhance hydrogen interaction between structural directing agent of triblock copolymer F127 and polymeric carbon precursor of resorcinol–formaldehyde resins. The obtained carbons have a hexagonal pore system, uniform pore size of ∼5.0 nm and high BET surface area of ∼758 m2/g. The prepared mesoporous carbons were used as catalyst for dehydrogenation of propane, exhibiting high catalytic activity and stability. After 50 h time-on-stream, the propane conversion of 12.1% was observed with propylene selectivity of 95.1% in the direct dehydrogenation process, while the propane conversion of 20.1% with propylene selectivity of 25.8% in oxidative dehydrogenation process. It has been found that the surface basic groups are active sites.

The example of palladium-catalyzed intermolecular cyclization for the synthesis of various diarylfurans in which one of the aromatic rings originates from the phenolic part of the starting ester and the other one from PhI(OAc)2 has been reported. The reaction is carried out through two steps: the rearrangement of palladium-associated iodonium ylides to form o-iodo diaryl ether and then palladium catalyzed intramolecular direct arylation. This reaction can tolerate a variety of functional groups and is alternative or complementary to the previous methods for the synthesis of diarylfurans.

Ni–V–O series catalysts for the oxidative dehydrogenation (ODH) of propane were prepared and characterized by BET, XRD, H2-TPR, O2-TPD-MS and electrical conductivity. At 425°C a C3H6 selectivity of 49.9% was observed on Ni0.9V0.1O Y at a C3H8 conversion of 19.4%, and the obtained selectivity is almost two times higher than that over NiO at the roughly same conversion of C3H8. The mobile oxygen species created by the interaction of NiO and V2O5 has been found in the composite catalysts by O2-TPD-MS and electrical conductivity studies, which seems to be responsible for the enhanced selectivity of the propane oxidative dehydrogenation.

The oxidative dehydrogenation (ODH) of propane was investigated on Ni-V-O catalysts in a wide range of vanadium contents (5-40%). The addition of a small amount of vanadium significantly increased the catalytic activity of NiO for oxidative dehydrogenation of propane to propene. The formation of propene has a good correlation with the coexistence of NiO and Ni3V2O8. This result strongly suggests that a synergetic effect exists between them in NiXV1-XOY (X = 0.95 to 0.6). The best results were obtained with a high Ni/V ratio (e.g. X = 0.95 to 0.85). The active sites and selective oxygen species are discussed. The influence of the catalyst preparation technique and the redox properties of the catalyst were also examined.

The addition of reducible metal oxides as promoters shows a positive effect on the catalytic behavior of lanthanum vanadate (LaVO4). A C3H6 yield increase of 6.5% is observed at 500 °C on molybdenum-promoted LaVO4, which can be attributed to the change of the redox properties, the blocking of the strong oxidation sites of the catalysts and to an increase of the accessibility of the labile oxygen toward the reactant. The influence of the catalyst preparation method and of the Mo loading as well as the additional promoting effect of CO2 in the gas feed was also examined.

The oxidative dehydrogenation of propane on rare earth vanadates is always in competition with the total oxidation of the alkane which leads to the formation of CO 2 and CO. Addition of CO 2 into the feed results in an increased C 3 H 6 selectivity together with a decreased CO formation through the total oxidation of the alkane or the formed alkene. For the tested rare earth vanadates as well as for the niobium promoted catalysts an enhancement of the C 3 H 6 selectivity at isoconversion and thus of the C 3 H 6 yields is observed upon CO 2 addition into the feed.