Friday am 30- Environmental catalysis

30-K-01 - The local structures of transition metal oxides incorporated in zeolites and their unique photocatalytic properties 

Osaka Prefecture University, anDO ok.chem.o.sakafu-u.ac.jp. Japan 

Various microporous and mesoporous zeolite catalysts incorporated or encapsulated with transition metal cations such as Mo , or Ti into their frameworks or cavities were synthesized by a hydrothermal synthesis method. In-situ spectroscopic techniques and analyses of the photocatalytic reaction products have revealed that these transition metal cations constitute highly dispersed tetrahedrally coordinated oxide species which enable the zeolites to act as efficient and effective photocatalysts for the various reactions such as the decomposition of NO into N2 and O2 and the reduction of CO2 with H2O into CH3OH and CH4. The charge transfer excited triplet state of these oxides, i.e., (Mo - O ) , (V - O ), and 

30-0-02 - Characterization and performance of oc-framework FeZSM-5 in catalytic N2O decomposition 

Catalytic N2O decomposition was investigated over FeZSM-5 prepared by a novel exframework method. This method comprises the introduction of Fe in the MFI framework, followed by calcination and steam treatment to extract the iron to extra-framework positions. The ex-framework method induces superior activity for direct N2O decomposition, compared to FeZSM-5 catalysts prepared by solid and aqueous ion-exchange methods. The extraordinary catalytic performance of ex-FeZSM-5 is attributed to the highly dispersed state of the Fe in the zeolite matrix and the Fe(III)/Fe(II) redox behaviour of a significant fraction of the iron centers in the catalyst. 

---