EXAFS用于Ru置换的固-液相醇氧化催化剂的研究

对Ru置换的有效的固一液相醇氧化催化剂Ru—hydrotalcite、Ru—Co-Ce—CO3和Ru—spinels进行了EXAFS的对比研究，发现催化剂的活性组分均为单核的Ru。对比属于Ru—hydrotalcite类的两种催化剂Mg—Al—Ru—CO3和Co—Al—Ru—CO3，EXAFS的表征证实，后者由于Co替代Mg，Ru的氧化态升高，实验证实它的催化活性增加。对比属于Ru—spinel类的MnFe1．95Ru0．05O4和MnFe1．8Cu0．15Ru0．05O4催化剂，发现部分Cu替代Fe导致后者的催化活性增加，EXAFS也证实其中Ru的氧化态升高。而Ru—Co—Ce—CO3催化剂具有高的醇氧化活性的原因也是由于Ru的氧化态较高。由此可以证实，在这类Ru改性的催化剂中，Ru—O是反应的活性位，可有效地加速醇的氧化反应。

APPLICATION OF EXAFS CHARACTERIZATION IN THE Ru-SUBSTITUTED OXIDATIVE CATALYSTS IN SOLID-LIQUID CATALYTIC REACTION

The comparative study of Ru substituted liquid solid catalytic oxidative catalysts was performed with EXAFS characterization The characterization results showed that the active component of catalysts was monomeric ruthenium For two catalysts of Ru hydrotalcite type, Mg Al Ru CO 3 and Co Al Ru CO 3,the substitution of Co for Mg showed an increase of Ru oxidation state, which was verified by EXAFS characterization, and resulted in the rise of catalytic activity for alcohol oxidation For two catalysts of Ru spinel type,MnFe 1 95 Ru 0 05 O 4 and MnFe 1 8 Cu 0 15 Ru 0 05 O 4,the partial substitution of Fe for Cu also caused the increase of Ru oxidation state characterized by EXAFS,and also resulted in the rise of catalytic activity for alcohol oxidation For Ru Co Ce CO 3 catalyst,the increase of catalytic activity can also be attributed to the higher oxidation state of Ru In conclusion, for these Ru substituted catalysts, Ru O was identified as an active site to promote the reaction of alcohol oxidation