Xanthate functionalized PAMAM dendrimer (XFPD) chelating ligand for treatment of radioactive liquid wastes

• A new xanthate functionalized PAMAM dendrimer (XFPD) ligand is synthesized.
• XFDP effectively form complexes with various heavy metal ions at pH > 4.
• XFPD remove metal ions even at high ionic strength.
• Loading capacity of XFPD for Eu3+ and Cu2+ metal ions is 0.94 and 0.48 g g−1.
• XFPD has potential application in total decontamination of radioactive waste.

Xanthate functionalized PAMAM dendrimer (XFPD) chelating ligand, first of its kind, has been synthesized from hydroxyl terminated poly(amido)amine dendrimer. Studies on performance of XFPD in removal of Cu2+ and Eu3+ metal ions were carried out from aqueous solution. Investigation on quantitative removal of Cu2+ and Eu3+ metal ions at various pH revealed that XFPD effectively precipitates the metal ions at pH > 4 with settling time of about 3 h. In case of Cu–XFPD complex at pH > 6, settling requires the addition of coagulating agent like aluminium sulphate. The loading capacity of XFPD for Cu2+ and Eu3+ metal ions was estimated to be 0.48 and 0.95 g g−1, respectively. The XFPD chelating ligand deployed for treatment of radioactive liquid waste (RLW) showed that percentage removal of radionuclides were in the following order; 95Zr ≈ 154Eu ≈ 60Co (>99.8) > 144Ce (98.8) > 125Sb (83.3) > 106Ru (79.4) > 55Mn (54.3) > 137Cs (24.0). It has been demonstrated that XFPD chelating ligand has potential application in effective removal of various radionuclides from aqueous waste.