ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 28, Number 6
JKCSEZ 28(6)
December 20, 1984 

In order to elucidate the effect of alkali promoter on chemisorption of carbon monoxide on silica supported transition metal catalysts we have investigated the infrared spectra for carbon monoxide chemisorbed on silica supported nickel with and without potassium coating within the frequency range of 1800 ∼ 2100cm-1 at various nickel concentrations and CO pressures. For the system without potassium coating the IR band intensities are found to greatly depend on the nickel conwgfra concentration although the band positions are scarcely affected. The band positions are nearly coincident with those reported by other people, but we have clarified that the 2057cm-1 band arises from Ni(CO)4 molecules physisorbed on silicagel. Besides this, the effect of temperature on CO chemisorption has also been investigated. On coating with potassium we have found that all the bands observed for the system without potassium coating suffer red shifts by 2 ∼ 10cm-1 and the formation of Ni(CO)4 is inhibited. Furthermore, we have recognized that on the nickel surface with potassium coating a disproportionation may occur to yield carbon dioxide molecules.