Amide functionalized carbon nanotubes: highly efficient sorbent for tetra and hexavalent plutonium

Selective phase separation of Pu⁴⁺ and PuO₂²⁺ was performed using N,N-dialkyl amide functionalized multi-walled carbon nanotube (AFMWCNT). The sorption kinetics followed a pseudo second order kinetics with rate constants of 2.50E-05 g mg^-1 min^-1 and 4.30E-05 g mg^-1 min^-1 for Pu⁴⁺ and PuO₂²⁺ respectively. The sorption proceeds via heterogeneous, non-ideal multi-layer adsorption following Freundlich isotherm. The radiolytic stability of AFMWCNT and the stripping behavior of plutonium from the loaded AFMWCNT were also investigated and finally AFMWCNT were employed for the processing of simulated high level waste solutions originating from Research Reactor (RR) and Fast Breeder Reactor (FBR). (author)