Preparation,Characterization And Catalytic Performance Of Ni Supported Catalyst In Hydrogenation Of DCPD Petroleum Resin

DCPD alicyclic C5 petroleum resin,referred to as DCPD petroleum resin,which is a thermoplastic functional resin produced by free radical polymerization or cationic polymerization of DCPD in the C5 olefins.The petroleum resin is modified by catalytic hydrogenation because there are a lot of double bonds in the molecular structure.Hydrogenated petroleum resin is highly saturated,hyaline and colourless,and strongly stable.It can be used as high value-added products,for example,hydrogenated petroleum resin can be applied to special adhesives,cosmetics,printing and many other fine chemical industries.In this paper,the research on the preparation,catalytic performance and characterization of Ni supported catalyst in hydrogenation of DCPD petroleum resin was carried out.The influence of different factors on the catalytic performance was investigated.The surface and body structure of the catalyst were analyzed by N2 physical adsorption,H2 pulsing chemisorption,H2-TPR and XRD.The results show that the calcined Al2O3 at 900? has suitable specific surface area and large pore size to eliminate the resistance of macromolecules diffusion,so it is suitable as carrier.The alkaline-earth metal oxides can obviously improve the thermal stability of Al2O3,and promote the dispersion of the active metal(Ni)on catalyst surface.MgO shows the best modified performance to catalyst,on the one hand,MgAl2O4 spinel which could be formed of MgO and Al2O3 is going to inhibite the sintering and phase transition of Al2O3,on the other hand,MgO combine with NiO to form MgO-NiO solid solution,which will increase the dispersion rate of Ni on catalyst surface,and the optimum loading of MgO is 2%.The catalyst prepared by stepwise impregnation shows higher catalytic activity than the co-impregnated catalyst.The results of research show that loading of active metal(Ni)in the optimal catalyst is 25%,and Ni(NO3)2 is more suitable as the Ni source of hydrogenation catalyst.In this paper,the technological conditions for the hydrogenation of DCPD petroleum resin were studied.Under the conditions of reaction temperature between 260 and 280?,pressure for 8MPa and time for 7?14h,high-quality hydrogenated petroleum resin can be obtained(bromine value is less than 1 gBr/100 g,softening point>83?,and looks hyaline&colourless).The study on the hydrogenation mechanism of DCPD petroleum resin shows that in-diffusion during reacting is the rate control step,and reducing theparticle size of catalyst can obviously eliminate the effect of in-diffusion in the reaction process,meanwhile,the reaction transit into kinetic zone rapidly.