Catalytic features of supported and unsupported ruthenium containing polyoxomolybdate anion (Ru
2Mo
14) were evaluated using the methanol transformation reaction. Decomposition of methanol into hydrogen (H
2) and carbon monoxide (CO) predominantly occurred over unsupported Ru
2Mo
14 whereas no acid-catalyzed reaction (formation of dimethyl ether, DME) occurred indicating that Ru
2Mo
14 had a weak acidity or had no acidity. Ru
2Mo
14 was homogeneously loaded up to
ca. 40 wt% on silica and titania that had been chemically modified with
N -(2-aminoethyl-3-aminopropyltrimethoxysilane. Ru
2Mo
14 catalysts supported on these modified supports exhibited higher conversion of methanol than Ru
2Mo
14 catalysts either unsupported or supported on unmodified supports, indicating that Ru
2Mo
14 was highly dispersed on the modified supports. Even in the presence of water vapor, no steam reforming of methanol or shift reaction of CO occurred over the supported Ru
2Mo
14 catalysts. Ru
2Mo
14 catalyst supported on modified alumina support converted methanol to DME by acid-catalyzed reaction together with the decomposition products, CO and H
2, indicating that the Ru
2Mo
14 catalyst supported on modified alumina possessed strong acidity. FT-IR measurement of the methanol species adsorbed on Ru
2Mo
14 catalyst supported on modified alumina and the contact time dependency of this reaction suggested that methanol decomposition proceeded via formation of formaldehyde and subsequent decomposition into CO and H
2.
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