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利用ＴＰＲ、Ｈ_２－ＴＰＤ技术，考察了氢气氛下的Ｐｔ－Ｍｏ／Ａｌ_２Ｏ_３和Ｐｔ－Ｃｏ－Ｍｏ／Ａｌ_２Ｏ_３催化体系中物种和电荷交换的现象和规律，揭示了Ｐｔ和Ｃｏ在表面Ｍｏ物种还原过程中助剂作用的本质．Ｐｔ－Ｍｏ／Ａｌ_２Ｏ_３的ＴＰＲ、Ｈ_２－ＴＰＤ结果证明，由于微量Ｐｔ参与了表面Ｍｏ物种还原时的物种和电子交换，有效地降低了其还原温度．Ｒｔ－Ｍｏ／Ａｌ_２Ｏ_３在氢还原过程中，氢和Ｍｏ容易形成载有活动氢的氢物种，并储存在催化剂表面，这种活动氢在Ａｒ中，甚至Ａｒ－Ｈ２混合气中可以释放出来。Ｐｔ－Ｃｏ－Ｍｏ／Ａｌ２Ｏ３的研究结果表明，Ｃｏ可以进一步促进Ｍｏ的还原．在样品预还原过程中，氢和Ｃｏ可以形成氢物种，其上的氢具有更强的可动性，很容易溢流到Ｍｏ物种的边上促进其还原．根据以上规律可以推测，加氢脱硫催化剂中Ｃｏ和贵金属的作用是使催化剂更容易形成低价的配位不饱和的钼中心，也就是ＨＤＳ活性中心．
The phenomena and rules of species and charge exchange in Pt-Mo / Al_2O_3 and Pt-Co-Mo / Al_2O_3 catalytic systems under hydrogen atmosphere were investigated by using TPR and H_2-TPD techniques. The results showed that the reduction of Pt and Co on the surface Mo species The role of additives in the nature. The results of TPR and H 2 -TPD of Pt-Mo / Al 2 O 3 show that the trace Pt effectively reduces the reduction temperature due to its participation in species and electron exchange during the reduction of surface Mo species. Rt-Mo / Al_2O_3 During hydrogen reduction, hydrogen and Mo easily form hydrogen species carrying active hydrogen and store on the surface of the catalyst. Such active hydrogen can be released in Ar and even Ar-H2 gas mixture. The results of Pt-Co-Mo / Al2O3 show that Co can further promote the reduction of Mo. During sample pre-reduction, hydrogen and Co can form hydrogen species. Hydrogen is more mobile and can easily overflow to the side of Mo species to promote its reduction. According to the above rules, it can be speculated that the role of Co and noble metal in the hydrodesulfurization catalyst is to make the catalyst more easily form a low-cost coordinated and unsaturated molybdenum center, that is, an HDS active center.