The hydrogenation of nitrogen-containing heterocyclic compounds and their derivatives to obtain the corresponding valuable products is of great practical significance. In this work, a highly active and selective Ni/NC hydrogenation catalyst was developed by utilizing melamine-modified high-specific surface carbon (NC) as a carrier for nickel nanoparticles (NPs), which showed excellent catalytic activity in the selective hydrogenation of methyl nicotinate, where the Ni/NC catalyst was first used for this reaction (selective hydrogenation of methyl nicotinate). It was found that nitrogen species on the surface of NC significantly promoted the decomposition of the nickel precursor and the high dispersion of nano-Ni, which effectively affected the agglomeration of the nickel metal, resulting in the distribution of nickel metal with a smaller particle size. In the selective hydrogenation of methyl nicotinate under mild conditions (130 degrees C, 3 h), the conversion of methyl nicotinate reached the optimal catalytic activity over the catalyst of 10% Ni/NC-1-M-I-300, in which the conversion of methyl nicotinate was 98.5% and the selectivity of methylpiperidine-3-carboxylate was 97.2%. After 5 recycles, the catalyst maintained a conversion of 95.4% for methyl nicotinate. The Ni/NC catalyst has good substrate adaptability in the selective hydrogenation of N-heterocyclic carboxylate, O-heterocyclic carboxylate, and aromatic carboxylate.

This work has for the first time reported the construction of strong Lewis acidity through one route of pre-calcining octahedral Zr-MOF material, which was synthesized by the rotating hydrothermal crystallization method with regular octahedral structure, large specific surface area and very uniform particle size. After low-temperature calcination, the resulting material Zr-MOF-R-X-Cal did retain basically an intact structure of Zr-MOF-R precursor and became more hydrophobic, as characterized by XRD patterns, SEM/TEM images and WCA angles. More importantly, the surface Lewis acidity and Lewis acid ratio on the calcined materials were significantly enhanced. Thus-calcined materials have exhibited highly catalytic activity for selective isomeriza-tion of alpha-epoxypinane to campholenic aldehyde. As we know, campholenic aldehyde (CA) was an important intermediate for the production of sandalwood and drugs, and generally prepared by selective isomerization of alpha-epoxypinane on strong Lewis acid sites. Among the tested materials, Zr-MOF-R-300-Cal presented the best catalytic effect on this isomerization to obtain 95.9% conversion of alpha-epoxypinane and 82.4% selectivity of CA, much superior to the Zr-MOF-R precursor and those catalytic materials reported previously in the literature. This could be assigned with strong Lewis acidity and high Lewis acid content on the Zr-MOF-R-300-Cal material, as proven by NH3-TPD and pyridine-FTIR tests. In addition, the increase of surface hydrophobicity promoted surface diffuse, adsorption and mass transfer of substrate molecules. Notably, catalytic activity of the Zr-MOF-R-300-Cal material was not decreased a lot after repeated-use six times, indicative of its excellent stability.

以Ni(NO3)2·6H2 O和SiO2(Degussa)为原材料,利用超声/微波一体化方法合成催化剂10％Ni/SiO2,并对催化剂合成条件如合成方式、温度、时间、超声功率、微波功率等进行了探讨.之后对催化剂进行XRD、BET、SEM、TEM、XPS和H2-TPR等表征,发现超声微波一体化合成的催化剂具有更大的比表面积、更小的金属粒径、粒子分布均匀以及形状较为规整.将催化剂用于催化环烯烃加氢反应时,烯烃转化率与相应环烷烃产物的选择性都较高,在90℃、1 h、超声功率为500 W、微波功率为150 W的合成条件下催化加氢活性最好,环己烯的转化率高达97.0％,产物环己烷选择性为100％.

The MOR supported cobalt complex materials were synthesized by ion exchange method and used to catalyze the epoxidation reaction of α-pinene with air. The liquid phase batch mode of epoxidation reaction was carried out under atmospheric pressure and aerobic conditions. Among the supported [Co(NH3)6]3+-zeolites catalysts, [Co(NH3)6]3+-MOR exhibited the best catalytic efficiency for the titled reaction, and high reaction conversion as well as epoxidation product selectivity were obtained for α-pinene and α-epoxypinane. Parametric studies were performed to examine the effect factors like the Co content, the solvent, the initiator, the substrate amount and the catalyst amount. The catalyst can be reused at least nine cycles without significant loss in activity towards epoxidation.

The epoxy compounds are useful intermediates and precursors in the production of fine chemicals and drugs. In the epoxidation reaction system, Co-MOF, a kind of cobalt-based heterogeneous catalytic material, has been widely studied for its simple synthesis, stable structure and excellent ability of molecular oxygen activation. For the first time, we used potassium persulfate as the initiator for the efficient air epoxidation reaction catalyzed by Co-MOF materials, which had better catalytic effects than aldehydes or peroxy compounds. As a new initiator, potassium persulfate reduces the reaction temperature and increased the amount of substrate olefins. In addition, potassium persulfate reduced the activation energy of the reaction, so that the ratio of olefin to initiator was further reduced, showing a better efficiency than initiators of aldehydes or peroxy compounds. Moreover, the application of potassium persulfate to the epoxidation reaction of other catalysts has also achieved good results.

In this work, a Cu-BTC material was first synthesized by a hydrothermal rota-crystallization method using cupric nitrate and benzene-1,3,5-tricarboxylate (BTC) as raw materials. Compared with a conventional hydrothermal method, this route greatly shortened the synthesis time of Cu-BTC to only 2 h. Cu-BTC was then treated under a N-2 atmosphere at different times and temperatures to obtain the derivative Cu/C-x-t with exceptional hydrophobicity (WCA of 146 degrees), where x represents the pyrolysis temperature and t was the pyrolysis time. The size effect of Cu NPs on carbon played a critical role in promoting the reaction efficiency. The thus-synthesized Cu/C-x-t material acted as an excellent catalyst for the quinoline hydrogenation in an aqueous medium. It was found that the catalytic reactivity of Cu/C attained the highest value at 600 degrees C for 2 h; the conversion of quinoline reached 95.2 mol % and the selectivity of 1,2,3,4-tetrahydroquinoline (THQ) was >99% under mild aqueous reaction conditions. This could be attributed to the hydrophobic surface structure of Cu/C-600 and the interaction between Cu nanoparticles and the surface C matrix, to form a special aqueous/oil microenvironment on the surface of the catalyst and to accelerate the interfacial reactions.

Here, we report the synthesis of spherical bimetal ZnCo-MOF materials by a hydrothermal rotacrystallization method and their catalytic activity on the air epoxidation of mixed biolefins enhanced by microwaves. The structural and chemical properties of the ZnCo-MOF materials were fully characterized by XRD, IR, SEM, TG, XPS, and NH3-TPD. The morphology of the material exhibited a three-dimensional spherical structure. From an NH3-TPD test of the ZnCo-MOF catalyst, it could be concluded that the Zn0.1Co1-MOF-H-150 rpm material had the highest acidic content and the strongest acidity among the catalysts synthesized by different methods, which gave the best performance in the epoxidation of mixed biolefins. The air epoxidation reaction was carried out under atmospheric pressure and microwave conditions, in the absence of any initiator or coreducing agent. Moreover, the Zn0.1Co1-MOF catalyst could be recycled six times without reducing the catalytic activity significantly, which showed the stability of spherical catalyst material under microwaves.