高分散率Ru/NaY觸媒之氣體吸附

Gas Chemisorption on Highly-dispersed Ruthenium Catalysts

陳郁文(Yu-Wen Chen) ； 廖錦男 ； 劉文宗

《化學》 44卷4期 (1986/12) Pp. 126-131

https://doi.org/10.6623/chem.1986040

摘要

文獻報導氫氣與一氧化碳在釘金屬上之化學吸附但至今尚無統一結論，而且甚少提及高分散率（微小顆粒）之觸媒。本研究即是以氫氣與一氧化碳之吸附來鑑定離子交換製備之高分散率Ru/NaY。H/Ru比隨金屬濃度減少而降低，此結果可歸因於顆粒效果與酸性沸石所引起之電子效果。一氧化碳吸附之紅外光譜也證實此結論。吾人提出一瞬間脫附法，此方法是目前鑑定高分散率之金屬觸媒表面積之最佳方法。

並列摘要

Although hydrogen chemisorption has been widely used for estimation of Ru metal surface area, the adsorption of stoichiometry of hydrogen on Ru are somewhat in doubt based on the literature. Two opposing factors, thermodynamic and kinetics, are operative in determing the adsorption states. An investigation into the chemi-sorption properties of zeolite-supported ruthenium catalysts has been carried out. Two preparation techniques, ion exchange with Ru(NH_3)_6Cl_3 and vapor impregnation by Ru_3(CO)_(12), have been used to introduce Ru into the NaY zeolite support. The experimental observed decreases of the H/Ru ratio with decreasing metal loading on Ru/NaY is ascribed to the effect of metal particle size and the Bronsted acidity of zeolites. Vapor-impregnated catalysts appeared to have less zeolite-metal interaction than ion-exchange ones. The flash desorption technique is by now the best method for determination of the Ru surface area/disprsion.