Efficient sequestration of plutonium from aqueous medium using nitrogen doped graphene nano walls

Nitrogen doped graphene nanowall(s) deposited on carbon paper is employed in sequestration of trace-level plutonium from aqueous solution using batch adsorption technique. Surface and structural characteristics of the sorbent are studied using SEM and Raman spectroscopy, respectively. Radiometric α-counting of the supernatant solution showed > 90% sorption at pH > 7. Visual Minteq modelling revealed that Pu(OH)₄ species is responsible for high sorption. Freundlich model evolved as the best fit, implying multilayer deposition on a heterogeneous surface as the mechanism of sorption. The combination of 10 M HNO₃ and EDTA resulted in 75% desorption. The results are promising for the sequestration of trace-level plutonium. (author)