Electron spin resonance and catalytic measurements of the oxidation of olefins on cadmium molybdate catalyst

Abstract

The formation of the e.s.r. single absorption line at g= 2.003 previously observed on bismuth molybdates and MoO₃ catalysts during interaction with olefins, has been investigated with CdMoO₄. The signal is formed only by interaction of adsorbed olefins with adsorbed oxygen and arises from an ill-defined radical located on the catalyst surface. The easy oxidation of this radical under usual catalytic conditions suggests that it may be an intermediate in a pathway of non-selective oxidation of olefins. Comparison between catalytic and e.s.r. results suggests that adsorbed molecular oxygen is active in this oxidation.