Analysis of some aspects of the catalytic behaviour of lanthanide oxides

The catalytic activity of eight lanthanide oxides (La 2 O 3 , CeO 2 , Pr 6 O 11 , Sm 2 O 3 , Eu 2 O 3 , Dy 2 O 3 , Ho 2 O 3 and Yb 2 O 3 ) prepared in our laboratory was studied. The test reactions were the decomposition of ethanol and 2-pentanol. These data and those previously reported for the decomposition of 1-butanol and 2-butanol were used to check the existence of correlations in the catalytic behaviour of the 4f oxides. Three different parameters, reaction rate, fractional selectivity and activation energy, were used to describe the behaviour of the catalysts. The validity of some general correlations involving the properties of Ln 3+ ions (Ln ≡ lanthanide) which have been proposed in the literature are discussed on the basis of the results obtained.