The Design Of The Metal Catalyst And Their Bonus In Unsaturated Hydrocarbons, The Application Of Polyol Reforming

The preparation of catalysts with an efficient activity and unique selectivitybecome one of the main directions of research among the scientists. This paper mainlyfocuses on the following areas and investigates the relationship between catalyticactivity, selectivity and its structure according to the relevant characterization andcontrol experiments.In this chapter, uniform Co-B amorphous alloy nanospheres with an averageparticle size of50nm were synthesized by chemical reduction of cobalt ion withborohydride in aqueous solution containing Bu4PBr and KCl. Then, Pd wasintroduced into this system by galvanic replacement reaction between Co and[PdCl4]^2-. Pd@Co-B catalysts with different Pd content could be obtained viaadjusting the amount of Na₂PdCl4in reaction mixture. During the liquid-phasehydrogenation of2-ethyl-2-hexenaldehyde, the as-prepared Pd@Co-B catalystsexhibited extremely active and more selectivity than the monometallic Co-Bamorphous alloy and the effect of different preparation method on the performancewas also investigated. The correlation of the catalytic performance to the structuralproperties has been tentatively established according to the TEM, XRD, XPS,H₂-TPD and related experiments.A series Pt/A1₂O₃catalysts modified with different metal oxides （TiO₂, CeO₂,La₂O₃and MgO） were prepared by sequentially incipient wetness impregnation andinvestigate the influence of various additives on catalytic activity and selectivity foraqueous-phase reforming of EG to hydrogen. Combination the reaction mechanismwith characterization （BET, NH₃-TPD, CO chemisorption, CO-TPD, H₂-TPR and soon） and experiment datas, we can find different additives not only have effects on thespecific surface area and surface acidity, but also can change the dispersion andelectronic state of Pt and further discuss the relationship between the change ofactivity and the catalysts’ structure. In addition, Pt/A1₂O₃modified with TiO₂remainits90%activity after120h on stream, showing enhanced stability than pure Pt/A1₂O₃which lose20%activity after only90h on stream.