Highly efficient removal of Pb2+ by a polyoxomolybdate-based organic-inorganic hybrid material {(4-Hap)4[Mo8O26]}

Abstract An organic-inorganic hybrid compound, (4-Hap) 4 [Mo 8 O 26 ] (4-ap = 4-aminopyridine) ( BUC-14 ), was synthesized via hydrothermal method, and utilized to conduct adsorptive uptake of typical heavy metal ion (Pb 2+ ), in which some key parameters on Pb 2+ adsorption and possible mechanism were investigated. The BUC-14 results in excellent adsorption performance for Pb 2+ from simulated wastewater, and the maximum uptake capacity is 1105.7 mg/g at 298 K. The kinetics behavior and equilibrium isotherm were well described using pseudo-second-order and Langmuir model, respectively. The adsorption process was thought to be divided two stages as electrostatic adsorption and ion exchange adsorption. Finally, the adsorption mechanism was proposed.