Perchlorate removal from aqueous solution with a novel cationic metal-organic frameworks based on amino sulfonic acid ligand linking with Cu-4,4′-bipyridyl chains

A novel metal organic frameworks (MOFs) material was fabricated by the solvothermal method and used as a high-efficiency adsorbent for the perchlorate removal from aqueous solution. The properties of material were characterized by SEM-EDS, FTIR and XRD. Various effects on adsorption process were systematically investigated, such as adsorbent dosage, pH, zeta potential, temperature, contact time and initial concentration of perchlorate. The results showed that the maximum sorption amount of perchlorate reached 133.5 mg/g at pH 7, and the perchlorate could be removed effectively over a broad range of pH value (from 2 to 11) at room temperature. The kinetics and equilibrium adsorption data could be fitted well by pseudo-first-order kinetic model and Langmuir model, respectively. Value of ΔG was found to be negative at all studied temperatures which confirmed the feasibility of process. The proposed adsorption mechanism was the co-effect of electrostatic force and ion-exchange between the perchlorate ions and MOFs material, which improved the adsorption capacity greatly. The results of the present study point to the possibility of developing a highly efficient adsorbent for removing perchlorate from aqueous solution under multi-adsorption forces.