Koji Nakano

Simultaneous catalytic removal of nitrogen oxides and diesel soot particulate over perovskite-related oxides

Abstract Catalytic performance of perovskite-type (ABO3) and K2NiF4-type (A2BO4) oxides for the reduction of NOx by diesel soot particulate in the presence of excess oxygen, that is, the simultaneous removal of NOx and soot, has been investigated. Their catalytic activity, evaluated from the ignition temperature of soot and selectivity to NOx reduction into nitrogen largely depended on both A-site and B-site cations and the partial substitution of potassium at A-sites prominently promoted both the activity and selectivity. These mixed metal oxide catalysts were superior to transition metal simple oxides and Pt/A12O3 in the selectivity for NOx reduction. The ignition temperature of soot in NO + O2 gas stream was lower than that in NO or O2 gas stream, implying that nitrogen dioxide accelerates the oxidation or activation of soot.

Simultaneous removal of nitrogen oxides and diesel soot particulates catalyzed by perovskite-type oxides

Abstract Perovskite-type oxides (ABO 3 ) catalyzed the simultaneous removal of NO x and diesel soot particulates in the presence of oxygen, and were superior to transition metal simple oxides in the selectivity for NO x reduction. Although the catalytic activity of perovskite-type oxides depended on both A-site and B-site cations, the substitution of potassium at A sites prominently promoted the oxidation of soot and the reduction of NO x .

Design of Catalyst Support for Deep Hydrodesulfurization of Gas Oil

Abstract Alumina-silica (Al2O3-SiO2) composite supports were examined to find the optimum state of support (i.e., composition and morphology). SiO2 content in the Al2O3-SiO2 support induced a shift of the main peak to higher frequency ascribed to an increased amount of Mo8O26 4−. A 75 wt% Al2O3-25 wt% SiO2 support had homogeneously dispersed alumina particles of smaller size with high crystallinity. Hydrodesulfurization (HDS) of straight-run gas oil and its conventionally hydrotreated straight-run gas oil was performed over NiMo sulfides supported on Al2O3-SiO2 composites. The high crystallinity of NMASA2-27 may be related to the high HDS and hydrogenation activity of NiMo sulfides due to its moderate interaction with the alumina surface.

Design of a molecular bilayer electrical device; dramatic change of A.C. impedance parameters due to phase transition of synthetic lipid bilayers on a patterned electrode under air atmosphere

A molecular bilayer modified electrode device shows dramatic change of alternating current (a.c.) electrical parameters due to phase transition of the bilayers under an air atmosphere.