One of the major drawbacks that hinder the industrial competitiveness of the calcium looping (CaL) process for CO2 capture is the high temperature (∼930-950 °C) needed in practice to attain full calcination of limestone in a high CO2 partial pressure environment for short residence times as required. In this work, the multicycle CO2 capture performance of dolomite and limestone is analysed unde...

TiO2 with tailored anatase/rutile composition has been prepared from the supercritical antisolvent (SAS) precipitation of a range of titanium alkoxides. The calcination of the SAS TiO2 was monitored by in situ powder X-ray diffraction to determine the optimal calcination conditions for the formation of a mixed anatse/rutile phase TiO2. The SAS precipitated material calcined at 450 °C produced a...

We have investigated chromium layers evaporated onto a thin alumina film at room temperature. The oxidation and reduction behavior of this model catalyst was compared to atomic layer deposition (ALD) and impregnated alumina supported catalysts using X-ray photoelectron spectroscopy (XPS) with a detailed analysis method utilizing asymmetric peak shapes to represent both metallic and oxidic state...

Formation of vanadia species during the calcination of ball milled mixture of V2O5 with TiO2 was studied by Raman spectroscopy in situ and at ambient conditions. It is found that calcination in air leads to fast (1–3 h) spreading of vanadia over TiO2 followed by a slower process leading to the formation of a monolayer vanadia. The calcinated catalyst showed higher activity during toluene oxidat...

The Dion-Jacobson phase niobate perovskite, KCa2Nb3O10, was prepared by the polymerized complex (PC) method. The corresponding proton-exchanged material, HCa2Nb3O10, was then exfoliated by reaction with tetra(n-butyl)ammonium hydroxide (TBAOH), yielding unilamellar colloidal nanosheets whose lateral dimensions increased with the final calcination temperature in the PC synthesis. By restacking t...

The kinetics of calcination of a high calcium type of limestone was studied. Ukpilla limestone found in the central region of Nigeria was studied. The limestone composition shows that the limestone has 51.29% calcium oxide and 41.53% loss on ignition and magnesium oxide content of 2.23%. The following parameters were determined; diffusion coefficient of lime layer, and mass transfer coefficient...

Calcium oxide (CaO) as carbon dioxide (CO2) adsorbent at the elevated temperature has been very well-received thus far. The CaO can be synthesized from natural calcium carbonate (CaCO3) sources through the reversible calcination-carbonation process. In the study, cockle shell has been selected as CaO precursors. The objectives of the study are to investigate the performance of calcination and c...

Thermal decomposition of dolomite in the presence of CO2 in a calcination environment is investigated by means of in situ X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The in situ XRD results suggest that dolomite decomposes directly at a temperature around 700 °C into MgO and CaO. Immediate carbonation of nascent CaO crystals leads to the formation of calcite as an intermediate...

−A study of the phase transformations generated by chlorine during the calcination of clays and kaolins is presented. The original samples and residues of the thermal treatment carried out in air and chlorine atmospheres are analyzed at different calcination times and temperatures. Sample characterization was performed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Xray micr...

We report herein a straightforward and label-free approach to prepare luminescent mesoporous silica nanoparticles. We found that calcination at 400 °C can grant mesoporous organosilica nanoparticles with strong fluorescence of great photo- and chemical stability. The luminescence is found to originate from the carbon dots generated from the calcination, rather than the defects in the silica mat...