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

Herein, barium tungstate BaWO4 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 BaWO4 nanocrystals is completed over several analytical techniques. TEM and SEM images show the formation of sphere-shaped BaWO4 structures in the nanoscale range. Also, XRD and FTIR revealed the successful preparation of BaWO4. 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 60Co at pH of 5 and 25 °C is 310.6 mg g-1, and 152+154Eu is 409.9 mg g-1. The thermodynamic studies illustrated that the sorption process was spontaneous and endothermic.