Takao Doi

Importance of a quasistable V4O9 to synthesize a highly crystalline VOHPO4·0.5H2O

Abstract The organic solvent method to synthesize a highly crystalline VOHPO4·0.5H2O was investigated. Firstly, reduction of V2O5 in alcohols was studied. It was clear that there existed a quasistable V4O9 state after reduction with isobutyl alcohol. When a mixture of isobutyl alcohol and benzyl alcohol was used, the reduction was relatively rapid and difficult to control. Secondly, pure, uniform and roseshaped precursor VOHPO4·0.5H2O was obtained by the dehydration-condensation of V4O9 and ortho-H3PO4 when ortho-H3PO4 was added dropwise. The balance in rates between addition of ortho-H3PO4 and the dehydration-condensation was important to prepare a uniform precursor.

Influence of alcohol solvents on characters of VOHPO4·0.5H2O prepared from V4O9 and ortho-H3PO4

Abstract The influence of alcohol solvents on the characters of VOHPO 4 ·0.5H 2 O, precursor of (VO) 2 P 2 O 7 , prepared from V 4 O 9 and ortho -H 3 PO 4 was studied. Valence of vanadium, XRD, SEM, TG/DTA, 31 P-NMR and Raman spectra were used for characterization. Depending on the alcohol solvent used, not only the morphology of particles, but also bulk and surface characters of the precursor VOHPO 4 ·0.5H 2 O were influenced.

141 Phenylacetate synthesis by oxyacetoxylation of benzene on Pd-catalyst

Abstract Phenylacetate (PhOAc) synthesis by oxyacetoxylation of benzene on Pd-based binary catalysts was studied in the liquid phase. Among the second components investigated, Sb, Bi and Te had a positive effect for catalytic performance of Pd. Deactivation was observed accompanying the elution of Sb, Bi and Pd. Notably less elution of Pd was observed when Pd was modified with Te. Screening of supports revealed a positive effect of ZrO2 for stability of the Pd-Te catalyst.