Effective removal of nitroimidazole antibiotics in aqueous solution by an aluminum-based metal-organic framework: Performance and mechanistic studies

The removal of antibiotics from wastewater has received extensive attention. An aluminum-based metal-organic framework (Al-TCPP) was synthesized as an adsorbent to remove ornidazole (ONZ) and metronidazole (MNZ). Al-TCPP has high adsorption capacities of 609.8 ​mg ​g−1 and 320.5 ​mg ​g−1 for ONZ and MNZ, respectively, superior to the reported adsorbents. And the adsorption data can fit well with the Langmuir model and the pseudo-second-order model. Besides, the adsorbent exhibits excellent anti-interference to coexisting salts and pH, which indicates that it has good practical application value. Furthermore, the possible adsorption mechanisms were proposed by FT-IR, XPS, Zeta potential, theoretical calculation, as well as the control experiments. These results indicate that hydrogen bonding interaction dominates the adsorption process. Therefore, Al-TCPP may have broad application prospects in purifying wastewater containing nitroimidazole antibiotics. The proposal of the dominant force is beneficial to the development of new adsorbents for the removal of antibiotics from aqueous solution.