One-pot synthesis of novel mesoporous FeOOH modified NaZrH(PO 4 ) 2 ·H 2 O for the enhanced removal of Co(II) from aqueous solution

One-pot synthesis of a novel mesoporous hydroxyl oxidize iron functional Na-zirconium phosphate (FeOOH-NaZrH(PO 4 ) 2 ·H 2 O) composites was firstly characterized and investigated its Co(II) adsorption from aqueous solution. Compared to NaZrH(PO 4 ) 2 ·H 2 O (65.7 mg⋅g −1 ), the maximum Co(II) adsorption capacity of FeOOH-NaZrH(PO 4 ) 2 ·H 2 O was improved to be 95.1 mg⋅g −1 . BET verified the mesoporous structures of FeOOH-NaZrH(PO 4 ) 2 ·H 2 O with a larger pore volume than NaZrH(PO 4 ) 2 ·H 2 O. High pH values, initial Co(II) concentration, and temperature benefited the Co(II) adsorption. Kinetics, isotherms, and thermodynamics indicated an endothermic, spontaneous chemisorption process. FeOOH-NaZrH(PO 4 ) 2 ·H 2 O has a better Co(II) adsorption selectivity than that of NaZrH(PO 4 ) 2 ·H 2 O. In particular, FeOOH-NaZrH(PO 4 ) 2 ·H 2 O exhibited an outstanding reusability after ten cycles of tests. The main possible mechanism for adsorbents uptake Co(II) involved in ion exchange, electrostatic interaction, and -OH, Zr-O bond coordination based on FTIR and XPS analysis. This work presents a feasible strategy to prepare novel modified zirconium phosphate composites for extracting Co(II) from solutions and providing a new insight into the understanding of Co(II) adsorption in the real nuclear Co(II)-containing wastewater.