An alumina-supported nickel catalyst was prepared by impregnation of Ni2+ solution onto mesoporous alumina under microwave irradiation (denoted as M-Ni/Al2O3). For comparison, a catalyst with the same nickel content was prepared by conventional impregnation method (denoted as UM-Ni/Al2O3). Both M-Ni/Al2O3 and UM-Ni/Al2O3 catalysts were applied to the syngas (H2 + CO) production by methane oxy-s...

An alomina-based nano adsorbent was prepared by modification of the external surface of γ-alumina (γ-Al2O3) nanoparticles with functional groups of a new Schiff base 4-[(2-hydroxy-3-methoxy-benzylidene)-amino]-5-methyl-2,4-dihydro-[1,2.4]triazole-3-thione] “L”. In order to the removal of Cr(VI) from aqueous solutions, we used the reaction of the sodium dodecyl sulfate coated nano-alumina with L...

Alumina/zirconia (Al2O3/ZrO2) multilayer thin films were deposited on Si (100) substrates at an optimized oxygen partial pressure of 3 Pa at room temperature by pulsed laser deposition. The Al2O3/ZrO2 multilayers of 10:10, 5:10, 5:5, and 4:4 nm with 40 bilayers were deposited alternately in order to stabilize a high-temperature phase of zirconia at room temperature. All these films were charact...

In the present study, adsorption of Co(tsPc)-4 using γ-Alumina was investigated. γ-Alumina was prepared by gel combustion method. The XRD pattern revealed that the synthesized γ-Alumina is amorphous and SEM image showed its nanosize scale while BET surface area about 501 m2/g and pore size of 7 nm implies highly porous surface which is a characteristic property of a high-quality adsorbent. In t...

Transition aluminas, and especially the gamma type, are largely used as catalyst supports in refining and petrochemicals. Most studies focus on properties resulting from material texture and casting (specific surface, porous volume, pore shape and diameter). However, surface properties of alumina should be considered as well, as the catalytic activity is tightly related to the structure of expo...

Incipient wetness impregnation was used to deposit dispersed tin (Sn) atoms on γ-Al2O3. The morphology and structure of the catalysts were characterized using Raman, X-ray Photoelectron Spectroscopy (XPS), low energy ion scattering (LEIS) combined with N2-physisorption in situ infrared diffuse reflectance spectroscopy (DRIFTS) NH3 CO2 as probe molecules, H2- temperature-programmed reduction (H­...

In this study, preparation of nano-sized gamma alumina with high specific surface area and high yield by thereaction between aluminum nitrate and sodium carbonate, without using any surfactant is reported. Bohemite (Aluminum oxyhydroxide) was prepared as a precursor by strict control of pH and reaction temperature. The gel produced was purified by washing fol...

The characteristics of intrinsic electron and hole trapping in crystalline and amorphous Al2O3 have been studied using density functional theory (DFT). Special attention was paid to enforcing the piece-wise linearity of the total energy with respect to electron number through the use of a range separated, hybrid functional PBE0-TC-LRC (Guidon et al 2009 J. Chem. Theory Comput. 5 3010) in order ...

This article mainly concerns theoretical research on entropy generation influences due to heat transfer and flow in nanofluid suspensions. A conventional nanofluid of alumina-water (Al2O3-H2O) was considered as the fluid model. Due to the sensitivity of entropy to duct diameter, miniand microchannels with diameters of 3 mm and 0.05 mm were considered, and a laminar flow regime was assumed. The ...

In this study, the recovery of platinum and palladium from petroleum catalysts has been elaborated using a method consisting mainly of dissolving alumina substrate in sulfuric acid thereby concentrating the precious metals in the residue. The effect of dissolution temperature and time, concentration of sulfuric acid, and pulp density on the dissolution of alumina substrate was investigated syst...