【Abstract】 Supported rare earth catalysts were made from Nd（O-i-Pr）₃ and the halides, especially chlorides of the ⅠA and ⅡA groups, used as catalyst supporters, for studying the relationship between the composition of supporters and the selectivity of supported rare earth catalysts. It was found that the electronegativity of the ⅠA or ⅡA elements showed an obvious effect on the selectivity of the supported catalysts, i.e. the selectivity of the supported catalyst was increased with the increase in their electronegativity, as in the case of supported Ti-catalyst .This rule was also held as the supporters are magnesium halides.更多还原