Zirconia-carbon (ZC) composites were prepared via calcination of Zr-based metal organic frameworks, UiO-66 and amino-functionalized UiO-66, under N₂ atmosphere. The prepared composites were characterized using a series of instrumental analyses. The surface area of the ZC composites increased with the increase of calcination temperature, with the formation of a graphite oxide phase observed at 9...

recently, the al2o3–tio2–zro2 system has found valuable applications, particularly, as a support for nox storage–reduction (nsr) catalysts. nanocomposite powders were prepared from the co-precipitation method in inorganic precursors. the behaviors of mixed oxide nanoparticles under ultrasonic irradiation, such as dispersion, and crushing were studied. phase transformations, crystallite size, an...

The direct synthesis of hydrogen peroxide using supported gold palladium catalysts prepared by incipient wetness impregnation is described and discussed. The effect of an acid pre-treatment step on the activated carbon support prior to the deposition of the metals, together with the effect of the calcination temperature, has been investigated. The acid pre-treated samples all show superior acti...

Nanocrystalline ceria has been considered as support for carbon monoxide preferentially oxidation. In this study ceria was prepared by precipitation method and the effects of preparation conditions, such as pH of solution (8-10), aging time (1-12 hr), drying temperature (80-120 °C), calcination time (2-6 hr) and temperature (400-600 °C) were investigated on ceria synthesized powders properties....

There is great technological interest in elucidating the effect of particle size on the luminescence efficiency of doped rare earth oxides. This study demonstrates unambiguously that there is a size effect and that it is not dependent on the calcination temperature. The Y₂O₃:Eu and Gd₂O₃:Eu particles used in this study were synthesized using wet chemistry to produce particles ranging in size be...

Quantitative determination of Brønsted acid sites in acidic mordenite samples with varying proton concentrations has been studied using aqueous conductometric titration method. Conductometric titration of the ammonium form of mordenite with sodium hydroxide is feasible and the results indicate potential number of Brønsted acid sites. However, Brønsted acid sites concentration in acidic mordenit...

This article presents the research results on production and performance of palladium-only catalytic converters. Monolith is used as the catalyst carrier and gamma alumina as the substrate. Dipping method is used for monolith washcoating. Palladium as the active metal is impregnated on gamma alumina using wet impregnation to produce catalyst samples. The effects of factors such as percent solid...

Composite electrodes were prepared by adding 40 wt % La0.8Sr0.2FeO3 (LSF) into porous yttria-stabilized zirconia (YSZ) and their performance was studied as a function of time and calcination temperature. X-ray diffraction (XRD) patterns of the LSF-YSZ composites indicated an expanded lattice parameter after calcination above 1523 K, suggesting that Zr reacted with the LSF to form a Zr-doped per...

Amorphous sulfated zirconium hydroxide was promoted with iron or manganese via the incipient wetness technique, to give 0.5–3.5 weight% promoter in the final catalyst. An exothermic reaction during the calcination temperature ramp (to 823 or 923 K) leads to a rapid overheating (“glow”) of the sample. XRD shows that crystallization starts before and progresses during the overheating. The surface...

quantitative determination of br?nsted acid sites in acidic mordenite samples with varying proton concentrations has been studied using aqueous conductometric titration method. conductometric titration of the ammonium form of mordenite with sodium hydroxide is feasible and the results indicate potential number of br?nsted acid sites. however, br?nsted acid sites concentration in acidic mordenit...