CATALYTIC ACTIVITY OF LIQUID-PHASE REACTION OVER PEROVSKITE-TYPE OXIDE CATALYST SYNTHESIZED FROM HETERONUCLEAR METAL CYANO COMPLEX PRECURSOR

摘要

The perovskite-type oxide catalysts,LaFeO3 and SmFeO3,synthesized by the thermal decomposition of heteronuclear metal cyano complex precursors,La[Fe(CN)6]·5H2O and Sm[Fe(CN)6]-4H2O,respectively(CN method),were used as catalyst in liquid-phase organic reactions,cyanosilylation of benzaldehyde with TMSCN and Knoevenagel condensation of benzaldehyde with malononitrile.The catalytic activity of cyanosilylation over perovskite-type oxide was dependent on both calcination temperature and calcination time of heteronuclear metal cyano complex precursors.The catalytic activity of cyanosilylation for LaFeO3 was higher than that for SmFeO3 in low calcination temperature region(500-700 °C),being ascribed to the crystallinity of perovskite-type oxide.Considering the catalytic activities for two liquid-phase organic reactions performed in the present study,it was suggested that the high catalytic activity for cyanosilylation over LaFeO3 catalyst comes from the synergistic effect of acid and base sites formed on LaFeO3 catalyst.