Peculiarities of a liquid phase hydrogenation, namely lower diffusivity of components influencing the reaction rate and deactivation of catalysts by leaching, are discussed. A focus is on hydrogenation of aromatic com...Peculiarities of a liquid phase hydrogenation, namely lower diffusivity of components influencing the reaction rate and deactivation of catalysts by leaching, are discussed. A focus is on hydrogenation of aromatic compounds, whereas the following processes are evaluated: (l) partial hydrogenation of benzene to cyclohexene; (2) hydrogenation of aniline; (3) hydrogenation of diphenylamine; (4) preparation of aniline from nitrobenzene; (5) hydrogenation of chloronitrobenzenes; (6) hydrogenation of 4-nitrosodiphenylamine and 4-nitrodiphenylamine mixture. Processes (1) and (6) are typically carried out in the water-oil system. Generally, this type of system allows reaching a higher selectivity to desired products. In the case of hydrogenation of 4-nitrosodiphenylamine and 4-nitrodiphenylamine mixture, the water phase extracts a water soluble catalyst; which is recycled and used for condensation of aniline and nitrobenzene. Problems of reaction kinetics, as well as catalysts deactivation are here discussed.展开更多
Based on the polycondensation of bifunctional 2,2′-diamino-4,4′-bithiazole(DABT) and trifunctional 1,3,5-benzenetricarbonyl trichloride (BTC),a novel hyperbranched aromatic polyamide PBD was synthesized with excelle...Based on the polycondensation of bifunctional 2,2′-diamino-4,4′-bithiazole(DABT) and trifunctional 1,3,5-benzenetricarbonyl trichloride (BTC),a novel hyperbranched aromatic polyamide PBD was synthesized with excellent solubility and good thermal stability.The structure of the polymer was confirmed by FT-IR and 1H NMR spectrum.The calculated degree of branching of our product was 52%.By exploring the influence of several different solvent systems,the yield of the polymer increased in the solvent system of DMAc/LiCl.Two kinds of metal complexes were obtained by chelation of the polyamide with Cu2+ and Ni2+,and the metal contents of the complexes were determined by complexometric titration.The magnetic behaviors of the complexes were examined as a function of magnetic field strength at 5 K,and as a function of temperature (5–300 K) at a magnetic field strength of 2.4 × 106 A/m.The results indicated that the complexes were soft ferromagnetic materials with Curie-Weiss temperature at 102 K and 53 K,respectively.展开更多
文摘Peculiarities of a liquid phase hydrogenation, namely lower diffusivity of components influencing the reaction rate and deactivation of catalysts by leaching, are discussed. A focus is on hydrogenation of aromatic compounds, whereas the following processes are evaluated: (l) partial hydrogenation of benzene to cyclohexene; (2) hydrogenation of aniline; (3) hydrogenation of diphenylamine; (4) preparation of aniline from nitrobenzene; (5) hydrogenation of chloronitrobenzenes; (6) hydrogenation of 4-nitrosodiphenylamine and 4-nitrodiphenylamine mixture. Processes (1) and (6) are typically carried out in the water-oil system. Generally, this type of system allows reaching a higher selectivity to desired products. In the case of hydrogenation of 4-nitrosodiphenylamine and 4-nitrodiphenylamine mixture, the water phase extracts a water soluble catalyst; which is recycled and used for condensation of aniline and nitrobenzene. Problems of reaction kinetics, as well as catalysts deactivation are here discussed.
基金supported by the National Natural Science Foundation of China (20674071)the National Basic Research Program of China (973 Program,2005CB623800)
文摘Based on the polycondensation of bifunctional 2,2′-diamino-4,4′-bithiazole(DABT) and trifunctional 1,3,5-benzenetricarbonyl trichloride (BTC),a novel hyperbranched aromatic polyamide PBD was synthesized with excellent solubility and good thermal stability.The structure of the polymer was confirmed by FT-IR and 1H NMR spectrum.The calculated degree of branching of our product was 52%.By exploring the influence of several different solvent systems,the yield of the polymer increased in the solvent system of DMAc/LiCl.Two kinds of metal complexes were obtained by chelation of the polyamide with Cu2+ and Ni2+,and the metal contents of the complexes were determined by complexometric titration.The magnetic behaviors of the complexes were examined as a function of magnetic field strength at 5 K,and as a function of temperature (5–300 K) at a magnetic field strength of 2.4 × 106 A/m.The results indicated that the complexes were soft ferromagnetic materials with Curie-Weiss temperature at 102 K and 53 K,respectively.