Study On Hydrogenation Catalyst For C5Petroleum Resin

C5hydrogenated petroleum resins are widely used in hot-meltadhesives, coatings, rubber, inks, paper and other industries. Thoughhydrogenation technology of C5petroleum resin is already quite matureabroad, only a few companies are capable to produce C5hydrogenatedpetroleum resin at home by importing foreign catalysts and supportingprocesses. At present, the demand for C5hydrogenated petroleum resin inour country far exceeds the supply. Therefore, it is urgent that we shouldaccelerate the development of the technology and catalysts forhydrogenation of C5petroleum resin, especially development of thecatalysts.The performance and use of the C5hydrogenated petroleum resinwere mainly introduced, and then the technical difficulties and the researchprogress on the catalyst for the hydrogenation of C5petroleum resin weresummarized in this paper. On this basis, a series of hydrogenation catalysts including Pd system, sulfide system and phosphide system, were prepared,and their catalytic activities of the hydrogenation reaction of C5petroleumresin were evaluated. The reason for deactivation of Pd-based catalystsused in hydrogenation of C5petroleum resin were investigated bythoroughly characterized and analyzed the Pd/Al₂O₃catalyst before andafter deactivation by techniques such as BET, XRD, TEM, ICP-MS.The experimental results indicated that the carrier Al₂O₃was moredesirable than SiO2for being used as the support of Pd-based catalysts forhydrogenation of C5petroleum resin. The carrier with larger poresdisplayed better catalytic activity and stability in hydrogenation ofmacromolecule such as C5petroleum resin.3wt%Mg1wt%Pd1wt%Pt/S2-Al₂O₃, i.e. the optimum Pd based catalyst, was finally obtained throughcarrying out a series of experiments. The Bromine value and softeningpoints of hydrogenated products were averagely below2g/100g and86℃,showing a good performance of the catalyst. Although the3wt%Mg1wt%Pd1wt%Pt/S2-Al₂O₃exhibited excellent catalytic activity, itstill became inactive as the reaction time increased. This might be themajor reason why its industrial application is limited. The characterizationresults revealed that the catalyst deactivation were attributed to thesynergistic effect of sulfur poisoning, decrease of specific surface area anddeposition of inorganic salts on the catalyst surface, of which sulfurpoisoning might had exercised the greatest influence. NiWS and NiMoS catalysts were also applied in hydrogenationreaction of C5petroleum resin. Experimental results showed that sulfidecatalysts had high hydrogenation catalytic activity and stability, but leadingto badly pyrolysis of products. Addition of Mg promoter cann’t solve theproblem, insteading of reducing hydrogenation activity. Ni₂P catalystshowed excellent hydrogenation catalytic activity and stability inhydrogenation reaction of C5petroleum resin, because of its stablecrystalline phase. Though pore volume and specific surface area ofNi₂P/SiO2were both decreased, Ni₂P catalyst can keep favorableperformance. Bromine value and softening point of the products were keptbelow1g/100g and above75℃,respectively.