الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
WO3 was synthesized via a simple chemical precipitation method from acidic media in two forms; bulk and nano (by using the hydrothermal route). The analytical tools of XRD, FT-IR spectroscopy, SEM, HRTEM, dynamic light scattering (DLS), EDX, thermal analysis (TGA and DTA) and nitrogen adsorption/desorption chromatography were used for characterization of the synthesized sorbents. The optimum bulk WO3 (precipitated from 0.1 M HCl and dried at 100°C), of 0.2 m particle size, achieved Q50% of 19.74×10-2 mmol Cs/g and a maximum sorption capacity (determined from Langmuir model) of 264.55, 332.23 and 423.73 mg Cs/g at 25, 40 and 60 °C. The optimum nano WO3 (precipitated from 0.1 M HCl, autoclaved in the hydrothermal reactor at 100 °C and dried at 100 °C), of 52 nm particle size, achieved maximum sorption capacity of 374.53, 406.50 and 431.03 mg Cs/g at 25, 40 and 60 °C, respectively. The sorption process kinetics of radiocesium on both of bulk and nano WO3 sorbents were found to follow pseudo 2nd order and film diffusion mass transfer models, While the sorption isotherms of radiocesium were found to follow Langmuir model in both cases. The sorption process in both cases was found to be physical in nature, nonspontaneous and endothermic. Bulk WO3 was successfully used as a base material for 137Cs/137mBa chromatographic column generator and as a core of 134Cs sealed source.