Attrition of six different limestones was studied during calcium looping cycles for CO2 capture in a lab-scale fluidized bed apparatus. The tests were carried out under realistic conditions representative of a process with calcination in an oxy-firing environment. The focus of the activity was to investigate the effect of the presence of SO2 both in the calcination and in the carbonation stages...

We report on the synthesis of TbMnO3 nanoparticles by chemical co-precipitation route and their structural, chemical bonding, magnetic and dielectric properties. It is shown that the interesting multiferroic properties of this system as reflected by the concurrent occurrence of magnetic and dielectric transitions are retained in the nanoparticles (size ~40 nm). However, the nanoparticle constit...

X-ray photoelectron spectroscopy (XPS) technique was employed to characterize Al2O3-TiO2 support and MoO3/Al2O3TiO2 catalyst calcined at different temperatures from 773 to 1073 K. The Al2O3-TiO2 (1:1.3 mole ratio) binary oxide support was obtained by a coprecipitation procedure with in situ generated ammonium hydroxide. A nominal 12 wt.% MoO3 was impregnated over the calcined (773 K) support by...

pure and zno-doped ni0.1co0.9fe2o4 catalyst were prepared by co-precipitation method and thermal decomposition in air calcinated at 400-700°c and that treated with different amounts of zinc nitrate (0.46-2.25 w% zno). x-ray powder diffractometry, scanning electron microscopy (sem) and bet analysis of nitrogen adsorption isotherms investigated the crystalline bulk structure and the surface area ...

In this study, an effective low-temperature method was developed, for the first time, for the synthesis of bismuth titanate nanobelts by using Na2Ti3O7 nanobelts as the reactants and templates. The experimental procedure was based on ion substitution followed by a nanoscale solid-state reaction. In the first step, Na2Ti3O7 nanobelts were soaked in a bismuth nitrate solution where ion substituti...

Titanium dioxide (TiO(2)) nanofibers in the anatase structure were successfully prepared via electrospinning technique followed by calcination process. The morphologies, crystal structure, surface area, and the photocatalytic activity of resulting TiO(2) nanofibers were characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffracti...

The interaction of vanadium oxide and niobium oxide with A1203 and TiO2 supports is examined with Raman spectroscopy. The Raman spectra of the supported metal oxides reveal that the strong interaction of the metal oxides with AI203 and TiO2 supports results in the formation of two-dimensional surface metal oxide overlayers. The surface vanadium oxide overlayers are unstable to high calcination ...

A one-dimensional mathematical model was developed for the simulation of limestone calcination in rotary kilns. The model is comprised of ordinary differential equations derived from mass and energy conservation principles. The system of equations is solved by a fourth-order Runge-Kutta method. The model predicts, in the axial direction, temperature profiles for the bed of particles, the gas ph...

Rapid thermal treatments potentially allow for a significant reduction in production time of ceramic multilayered membranes, in turn aiding increased industrial application of these membranes and accelerating research on their development. Two methods are proposed for the rapid thermal treatment of thin supported inorganic membrane films. Both methods involve an instant increment in temperature...

A series of copper oxide (CuOx) catalysts supported by oxidized multi-walled carbon nanotubes (OMWNT’s) were prepared by the wet impregnation method for the low temperature (200 °C) selective catalytic reduction of nitrogen oxides (NOx) using NH3 as a reductant agent in the presence of excess oxygen. These catalysts were characterized by FTIR, XRD, SEM-EDS, and H2-TPR meth...