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为扩展 H-O 滴定法至双金属催化剂分散度的测定,对含 Pt 或不含 Pt 的 Re-,Ir-,Au-,Sn/Al_2O_3样品进行了研究。除参考地使用了脉冲氢吸附技术外,并部分地与电子显微镜和程序升温脱附(TPD)技术结果进行了比较。观察到在新鲜催化剂时,Pt/Al_2O_3中由于第二金属组元的引入,产生了两种不同的金属相互作用行为。和 Pt 同属Ⅷ族的 Ir,及与之相邻的ⅦB 族金属 Re,使得在 H-O 滴定中的耗氢量增强;IB 金属 Au 和ⅣA 金属 Sn 则使之变弱。强化热处理样品的测定表明了金属颗粒的增长,它们抗烧结能力的顺序为:Pt-Ir/Al_2O_3≥Pt-Re/Al_2O_3>Pt/Al_2O_3>Au/Al_2O_3。
In order to extend the H-O titration to the determination of the bimetallic catalyst dispersion, Re-, Ir-, Au-, Sn / Al_2O_3 samples with or without Pt were investigated. In addition to using pulsed hydrogen adsorption as a reference, the results were compared, in part, with electron microscopy and temperature programmed desorption (TPD) techniques. It is observed that the introduction of the second metal component in Pt / Al_2O_3 resulted in two different metal interaction behaviors in fresh catalyst. And Pt belong to Group Ⅷ of Ir, and the adjacent Group VIIB metal Re, H-O titration in the hydrogen consumption increased; IB metal Au and Ⅳ A metal Sn weakened. The heat-treated samples show the growth of the metal particles. The order of their anti-sintering ability is: Pt-Ir / Al_2O_3≥Pt-Re / Al_2O_3> Pt / Al_2O_3> Au / Al_2O_3.