Evaluation of barium tungstate nanocrystals for the sorption of radioactive cobalt and europium from aqueous solutions.

Herein, barium tungstate BaWO 4 nanocrystals were chemically prepared and then estimated as inorganic sorbent material to eliminate the radioactive cobalt and europium from the waste stream. The characterization of BaWO 4 nanocrystals is completed over several analytical techniques. TEM and SEM images show the formation of sphere-shaped BaWO 4 structures in the nanoscale range. Also, XRD and FTIR revealed the successful preparation of BaWO 4 . Optimum factors affected by the sorption process are determined using batch mode. Sorption equilibrium was achieved after 60 min with the initial concentration of metal ion at 100 mg/L and at optimum pH five for both radionuclides, respectively. The different kinetic models are applied. The obtained data shows that the sorption process followed a pseudo-second order. The sorption capacity for 60 Co at pH of 5 and 25 °C is 310.6 mg g -1 , and 152+154 Eu is 409.9 mg g -1 . The thermodynamic studies illustrated that the sorption process was spontaneous and endothermic.