Evaluation of 1st and 2nd generation of poly(amidoamine) dendrimer functionalized carbon nanotubes for the efficient removal of neptunium

Herein, sorption of pentavalent neptunium from aqueous acidic solution was carried out onto 1st and 2nd generation of poly(amidoamine) dendrimer functionalized MWCNTs. The Np(V) sorption kinetics followed pseudo second order kinetics with rate constants of 1.4 × 10−4 and 6.84 × 10−4 g mg−1 min−1 for MWCNT–PAMAMG1 and MWCNT–PAMAMG2, respectively. The sorption of Np(V) onto MWCNT–PAMAMGn proceeded via chemisorption and the data fitted well to Langmuir isotherm model. MWCNT–PAMAMGn was found radiolytically stable up to 500 kGy dose of gamma radiation. Sodium carbonate was found to strip Np effectively from sorbent.