Background: Zeolitic imidazolate frameworks with three metals Zn, Co and Ag (ZIF-3M) and ZIF-67 were synthesized at room temperature and characterized with different techniques such as FESEM, BET, EDX and XRD. Then, the synthesized nanoparticles were successfully applied for the removal of levofloxacin from aqueous solutions. Methods: To optimize the significant factors (i.e., pH, adsorbent dose and contact time), the response surface methodology (RSM) was implemented based on Box-Behnken design (BBD) in each step, an appropriate amount of adsorbent was added to 30 ppm of a solution containing levofloxacin and the pH was adjusted to the desired value with 0.1 M HCl or 0.1 M NaOH. The mixture was stirred at room temperature and then centrifuged at 7500 rpm for 3 min. Results: The optimal conditions for each variable were performed using Box-Behnken design. Results revealed that ZIF-3M nanoparticles more efficiently remove levofloxacin than ZIF-67 in aqueous solution. Conclusion: In this research, new three metals ZIF (ZIF-3M) nanoparticles were synthesized with Ag, Zn and Co in aqueous solution and characterized by different techniques. Results indicated successful synthesis with preserving ZIF framework. Results indicated that ZIF-3M has more ability for the removal of levofloxacin than ZIF-67. Isotherm studies showed that the most suitable model for the adsorption of levofloxacin onto ZIF-3M has a good agreement with the Langmuier model.
