A rapid, safe and simple technique for the production of high purity strontium oxide powders via a chemical combustion process is reported. The combustion reactions were performed to optimize the fuel to oxidizer ratios in the reaction mixtures required to obtain pure SrO powders by varying the molar ratio of chemical precursors and the temperature. The synthesized powders were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectrometry, infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and N 2 -physisorption measurements. The results indicate that crystalline SrO was obtained using a 1:1 strontium nitrate: urea molar ratio at 1000°C after 5 minutes. In addition, high-purity, homogeneous and crystalline SrO powders were easily produced in a short time via a chemical combustion process.

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In this work, γ-Al2O3 materials were successfully obtained by solution combustion and modified via ball milling. These improved materials were systematically investigated as solid adsorbents of accessible surface areas, large pore volumes, and narrow pore size distribution for the CO2 capture. These studied solid adsorbents can provide an additional contribution and effort to develop an efficient CO2 capture method as means of alleviating the serious global warning problem.

The ball milling effect on the sorption properties of tribasic calcium phosphate (TCP) is presented. The materials obtained were characterized by X-ray diffraction, SEM, particle size and specific surface area. The specific surface area of the prepared TCP prepared sample was 60.55 m 2 /g and unexpectedly decreased to 12.57 m 2 /g for samples where milling time was 15 hrs. In TCP samples with a milling time of 5 and 10 h, the specific surface values also diminished to 16.81 and 15.11 m 2 /g, respectively. Fe atoms were found in the milled TCP samples as XRD and EDS techniques revealed. An increase of Cr(VI) ion sorption with milling time was observed with a maximum chromium sorption of 14.0 x 10 -4 meq/g. This increasing Cr(VI) sorption may be due to the presence of the Fe atoms found in the milled TCP samples.

Polypropylene (PP) grafted with dimethylaminoethylmethacrylate (DMAEMA), was prepared by irradiation with a ⁶⁰Co γ source. The obtained PP-<em>g</em>-DMAEMA was used to study the Cr(VI) ion adsorption as a function of contact time, initial pH, initial concentration of metal ion and temperature. Chromium adsorption data on PP-<em>g</em>-DMAEMA at various initial concentration fit well the Freundlich and Langmuir isotherms. The maximum adsorption capacity (a_max) was found to be 0.3103 × 0^-4 mol g^-1. The thermodynamic parameters ΔH⁰, ΔG⁰ and ΔS⁰ were estimated showing the adsorption process to be exothermic and spontaneous.