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
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.
