An experimental study was conducted to investigate the potential use of phosphogypsum (PG) to produce self-leveling underlayments. The study was designed in two stages. Initially a phosphoanhydrite (PA) was produced by heating phosphogypsum at temperatures of 350 °C, 450 °C, 550 °C, and 650 °C. Two periods of heating were applied (2 and 4 h). The formation of anhydrite was determined by thermog...

OF DOCTORAL DISSERTATION HELSINKI UNIVERSITY OF TECHNOLOGY P.O. BOX 1000, FI-02015 TKK http://www.tkk.fi Author Leif Backman Name of the dissertation Supported Cobalt Catalysts—Preparation, Characterisation and Reaction Studies Manuscript submitted Jan 23, 2009 Manuscript revised May 7, 2009 Date of the defence June 2, 2009 Monograph Article dissertation (summary + original articles) Faculty Fa...

Calcium oxide is one of the appropriate catalysts for biodiesel production. In this study, cheap and compatible with environment catalyst has been used. Mussel shell of Persian Gulf coast is one of the sources of calcium carbonate that is converted to calcium oxide at calcination temperature up to 950°C. Transesterification reaction was carried out at optimum condition of our previous study...

Zeolite activation is the first, but often overlooked, post-synthetic treatment needed to transform an as-made material into adsorbent or catalyst. Ozonation at low temperatures provides alternative for conventional calcination treatments, with important consequences zeolite stability and acidity. While sometimes used in context of emptying novel less thermally stable structures, a thorough loo...

Powder of La0.6Sr0.4CoO3-α (LSCO) was synthesized by a combined citrate-EDTA method. The as-synthesized LSCO powder was calcined, respectively at temperatures of 800, 900 and 1000 °C with different heating/cooling rates which are 2, 5, 10 and 15 °C min. The effects of heat treatments on the phase formation of perovskite phase of LSCO were investigated by powder X-ray diffraction (XRD). The XRD ...

In this work, nanostructured CeO2 microspheres with high surface area and mesoporosity were prepared by the coprecipitation method, in absence of a template. The reaction between cerium nitrate and concentrated formic acid produced cerium formate, at room temperature. Further, calcination at 300 °C yielded single-phase CeO2 microspheres, with a diameter in the range 0.5-2.6 μm, the surface of t...

In this paper, strontium ferrite (SrO.6Fe2O3) was synthesized by the sol-gel auto-combustion process. The thermal behavior of powder obtained from self-propagating combustion of initial gel was evaluated by simultaneous differential thermal analysis (DTA) and thermo gravimetric (TG), from room temperature to 1200°C. The as-burnt powder was calcined at various temperatures from 700-900°C to achi...

Reactive powders of stoichiometry Nd2(Ti2/3Al1/3)3O9-δ and thin films of (Ba0.7Sr0.3)TiO3 have been prepared by the conventional mixed-oxide method and the metal-organic deposition method, respectively. The corresponded phases after calcination and sintering are investigated by XRD diffraction. Single phase of Nd2(Ti2/3Al1/3)3O9-δ could be only obtained by sintering over 1400C for 4 h. (Ba0.7Sr...

Spinel-type ZnMn₂O₄ nanoparticles were synthesized via a simple and inexpensive microwave-assisted colloidal route. Structural studies by X-ray diffraction showed that a spinel crystal phase of ZnMn₂O₄ was obtained at a calcination temperature of 500 °C, which was confirmed by Raman and UV-vis characterizations. Spinel-type ZnMn₂O₄ nanoparticles with a size of 41 nm were identified by transmiss...