Next to the main aluminium ore, bauxite, an assemblage of aluminium hydroxides, aluminium oxides and other minerals (gibbsite, diaspore, boehmite, kaolinite, quartz, hematite, goethite, rutile, anatase, and alumogel), aluminium oxides find direct application in diverse industrial processes (e.g., refractory, abrasives, and watch-making industries) as well as in the gemstone sector. Corundum (Al...

To understand the formation of structural isomers alumina (Al2O3) on surfaces Fe–Cr–Al alloys, cathodoluminescence (CL), X-ray photoelectron spectroscopy (XPS), and diffraction (XRD) were used. The alloys annealed under oxygen at a low partial pressure to focus initial Al2O3. XRD revealed that corundum (α-Al2O3) was predominantly formed alloy after annealing approximately 1100°C, whereas γ-Al2O...

γ-Alumina is widely used as an oxide support in catalysis, and palladium nanoparticles supported by alumina represent one of the most frequently used dispersed metals. The surface sites of the catalysts are often probed via FTIR spectroscopy upon CO adsorption, which may result in the formation of surface carbonate species. We have examined this process in detail utilizing FTIR to monitor carbo...

Egyptian Petroleum Research Institute, Nasr City, Cairo, Egypt. Chemistry department, Faculty of Science, Taif University, KSA. _________________________________________________________________________________________ Nine alumina samples of various modification techniques were subjected to thermal analysis via thermogravimetric analysis (TGA) and differential thermal analysis (DTA), in order t...

. The nature of the formation allene and methylacetylene during dehydrochlorination 1,2-dichloropropane intermediate products (1-chloropropene-1, 2-chloropropene-1, 2-chloropropane, 3-chloropropene-1) on γ-Al2O3, CaX expanded clay made it possible to establish that main source is - 1-chloropropene-1, γ -Al2O3, appears mainly from 2-chloroprene. highest value allene: ratio was obtained 1,2-dichl...

This paper systematically studied the pore structure, crystal phase, surface acidity and chemical environment of aluminum boron-doped γ-alumina, by impregnating boron in period boehmite. The nitrogen adsorption, XRD, FTIR etc. technique was used to determine texture, crystallography, acid/base properties coordination. XRD spectrum boria-alumina have no significant change due addition boron. spe...

Dehydration of glycerol was performed over heteropoly acids (HPA), viz., silicotungstic acid (H-SiW), phosphotungstic acid (H-PW), and phosphomolybdic acid (H-PMo), supported high surface area γ-alumina (HSAI-S25) catalysts. Various physico-chemical studies of these supported catalysts indicate high dispersion of the active (HPA) species on the support surface. It was observed that the catalyst...

The radiation hardness and thermal stability of the electrical characteristics of atomic layer deposited Al2O3 layers to be used as passivation films for silicon radiation detectors with slim edges are investigated. To directly measure the interface charge and to evaluate its change with the ionizing dose, metal-oxide-silicon (MOS) capacitors implementing differently processed Al2O3 layers were...

By including phonon-assisted transitions within plane-wave density functional theory methods for calculating the x-ray absorption spectrum (XAS), we obtain Al K-edge XAS at 300 K two crystalline Al2O3 phases. The reproduces pre-edge peak α-Al2O3, which is not visible static lattice level of approximation. Configurations from Monte Carlo sampling γ-Al2O3 phase space correctly describe out three ...