Study On Synthesis Of Ru/Resorcinol-Formaldehyde Resin Microspheres Catalyst And Application In Catalytic Hydrogenation Of P-Chloronitrobenzene

Supported noble metal catalysts possess great promising for industrial applications.The development of new supported noble metal catalysts has both important implications for catalytic technology development and applications of catalyst.Chloroaniline is important intermediates for synthesis of organic fine chemicals,such as dyes,drugs,and pesticides.And the catalytic technology of supportednoblemetalcatalystsusedforcatalyzinghydrogenationof chloronitrobenzene to form chloroaniline get the widespread concern with its environmentally friendly,stable product quality and advanced technology,therefore,the development of new supported noble metal catalysts can bring more industrial significance for it.The supported ruthenium catalysts were prepared by impregnation using RF resin sphere as support and ruthenium trichloride trihydrate as precursor.Different reduction methods were used in the preparation of catalysts?such as reflux reduction,chemical reduction and hydrogen reduction?.And the supported ruthenium catalysts were first time used for catalyzing hydrogenation of p-Chloronitrobenzene to form p-Chloroaniline.FTIR?XRD?SEM?TEM and XPS were used to investigate the component?structure?morphology and surface electronic form of support and the supported ruthenium catalysts.The effects of reaction conditions?such as reaction time,reaction temperature,capacity of Ru,et al.?,reduction methods and addition of metal ions were investigated in the hydrogenation of p-Chloronitrobenzene to form p-Chloroaniline.Resorcinol and formaldehyde as raw materials,ethanol and water as solvent,ammonia as catalytic,in the preparation of RF resin microspheres.The characterization result showed that particle size of RF resin microspheres was about0.8?m,and microspheres also showed good dispersion,sphericity and sphere smooth surface.The supported ruthenium catalysts were prepared by impregnation using RF resin sphere as support and ruthenium trichloride trihydrate as precursor.The characterization result showed that the supported ruthenium catalyst was amorphous catalysts,Ru dispersed on the surface of support in flocculent form and Ru of the catalysts was in zero valence state or oxidation state of low valence.The effects of reduction method in the preparation of supported ruthenium catalysts on the catalytic and selectivity were studied.The results showed that the supported ruthenium catalysts prepared by conventional impregnation and reduced with reflux of isopropanol exhibited the best catalytic performance both on the conversions of p-Chloronitrobenzene and selectivities of p-Chloroaniline,100%and99.7%respectively.The hydrogenation of p-Chloronitrobenzene to form p-Chloroaniline was accomplished by supported ruthenium catalysts.The influence of reaction conditions was investigated.It is found that the conversions of p-Chloronitrobenzene was enhanced with the content of Ru increased,reaction temperature elevated,reaction time extended and hydrogen pressure increased.In contrast,the conversions of p-Chloronitrobenzene was decreased with the amount of p-Chloronitrobenzene increased.The change of the reaction conditions had little effect on the selectivities of p-Chloroaniline,and all were above 99%.The best reaction conditions were deionized that water as solvent,capacity of Ru 3wt%,rection time 3h,reaction temperature70?,hydrogen pressure 3MPa,n?p-Chloronitrobenzene?:n?Ru?=150:1.The influence of different metal ion Mⁿ⁺(Fe³⁺?Co²⁺?Cr²⁺?Sn²⁺?Sn⁴⁺?Ni²⁺)(Mⁿ⁺:Ru=1:1 molar ratio)to the catalytic hydrogenation activity and selectivity was investigated.The result showed that all different metal ions promoted the catalytic hydrogenation activity.Sn²⁺showed the best performance with the conversions of p-Chloronitrobenzene from 41.9%to 99.9%.The influence of the selectivities of p-Chloroaniline did not change significantly.