Removal of 137Cs and 90Sr from simulated low-level radioactive waste using tin(IV) vanadate sorbent and its potential hazardous parameters.

This study is concerned with the sorption of 137Cs and/or 90Sr from low-level radioactive waste using tin(IV) vanadate (SnV) sorbent fabricated by the precipitation technique. The structure and properties of SnV were studied using different analytical tools such as X-ray diffraction, X-ray fluorescence, Fourier-transform infrared, and scanning electron microscopy. Batch technique was used to investigate the sorption behavior of SnV towards 137Cs and/or 90Sr considering the influence of independent parameters including pH of the solution, contact time, and initial metal ions concentrations in simulation studies using the γ emitting isotopes 134Cs and 85Sr as representatives of 137Cs and 90Sr, respectively. The sorption efficiency values of 70.3% and 92.2% were respectively obtained for 134Cs and 85Sr at optimum conditions (pH = 6, Ci = 100 mg/L, and time = 120 min). The amount sorbed (mg/g) increases by increasing pH and temperatures. The pseudo-2nd-order kinetic is a reaction command. Isotherm is more relevant to a Langmuir at different reaction temperatures. The sorption process was endothermic and spontaneous. The adsorption efficiency of the composite material was studied in removing both cesium and strontium nuclides from real low-level radioactive waste. This study showed that the new material can be used as a promising material to retain 137Cs and 90Sr from real radioactive waste.

Synthesis, characterization and application of titanium oxide nanocomposites for removal of radioactive cesium, cobalt and europium ions.

New nanocomposite material containing TiO2/Poly (acrylamide-styrene sodium sulfonate) [TiO2/(P (AAm-SSS)] was prepared by in-situ intercalative polymerization of poly acrylamide (PAAm) and styrene sodium sulfonate (SSS) in the presence of TiO2 nanoparticles as inorganic filler. N, N-methylene bis acrylamide (MBA) was used as a cross linker. The polymerization process was performed using γ-radiation as reaction initiator. Moreover, new nanocomposite material containing poly styrene-TiO2 (PS-TiO2) was also prepared by ionic polymerization method. Styrene was catalytically polymerized by Ti(4+) via an ionic polymerization route to produce polystyrene (PS). The structure characteristics of the nanocomposites were investigated by XRD, TGA, SEM, surface area, and FTIR. The nanoparticles and nanocomposites were investigated for removal of some metal ions from aqueous solutions. The effective key parameters on the sorption behavior of radioactive cesium (Cs(+)), cobalt (Co(2+)) and europium (Eu(3+)) were investigated using batch equilibrium technique with respect to solution pH and contact time. The obtained results revealed that the equilibrium for Cs(+), Co(2+) and Eu(3)(+) is reached at 2-3 h for all nanocomposites. The data indicated that there is no significant change in the uptake between TiO2 nanoparticles and TiO2-PS. On the contrary, the uptake process is significantly improved using TiO2/(P (AAm-SSS) nanocomposite and the maximum experimental retention capacities for Cs(+), Co(2+) and Eu(3+) were found to be 120, 100.9 and 85.7 mg/g, respectively.