Keggin-type molybdovanadophosphoric acids loaded on ZSM-5 zeolite as a bifunctional catalyst for oxidehydration of glycerol

Glycerol is a promising renewable feedstock for the manufacture of C3 derivatives. We investigated the one-pass oxidehydrarion of glycerol through the dehydration of glycerol into acrolein, followed by the oxidation of acrolein. A novel bifunctional catalyst for this reaction was prepared by loading the Keggin-type molybdovanadophosphoric acid H3+xPVxMo12-xO40 (x = 0–3) on ZSM-5 (MFI) zeolite (Si/Al = 45) exhibiting both dehydration and oxidation activity. H5PV2Mo10O40 and H6PV3Mo9O40 were stable and dispersed on ZSM-5 zeolite, and the acidic property of the ZSM-5 zeolite was retained. The oxidehydration of glycerol was catalyzed by H5PV2Mo10O40 loaded on the ZSM-5 zeolite with high selectivity of acrylic acid. In-situ IR analysis suggests that acrolein molecules adsorbed on H5PV2Mo10O40/ZSM-5 were converted into acrylic acid due to the inhibition of side-reactions such as polymerization and auto-condensation, which induced coke formation, compared with the other Mo and V-based oxides loaded on ZSM-5 zeolite

An Interpretation of Martensitic Transformation in L1 2 -Type Fe 3 Pt from Its Electronic Structure

Partly ordered Fe 3 Pt is one of ferromagnetic shape memory alloys exhibiting a large magnetic field-induced strain in its martensite phase formed by a second-order-like martensitic transformation from the L1 2 -type structure to the so-called FCT martensite (L6 0 -type structure). We have investigated the origin of this transformation from their electronic structures calculated in the present study. A characteristic feature in the electronic structure is the existence of a relatively high peak in the density of states of the minority spin band just below the Fermi energy. This peak splits into two peaks by tetragonal distortion, and one of them shifts to lower energy by the distortion, suggesting that the band Jahn-Teller effect is the main cause for the transformation