Continuous adsorption removal of organic pollutants from wastewater in a UiO-66 fixed bed column

The UiO-66 particle adsorbents were prepared and characterized for the continuous adsorption removal of organic pollutants from wastewater in a fixed bed column. Metronidazole (MNZ), Rhodamine B (RhB), and phenol were chosen as model pollutants to study the adsorption mechanism. Adams-Bohart and Yoon-Nelson models were applied to fit the adsorption breakthrough curves. Regeneration techniques and stability of the UiO-66 adsorbents were studied. The results indicated that the UiO-66 particle was successfully applied for the continuous adsorption of organic wastewater and exhibited distinct differences. The high temperature is beneficial for RhB adsorption and the low temperature is beneficial for MNZ adsorption. Phenol wastewater shows low adsorption properties on UiO-66 particles. The maximum saturated adsorption capacity of UiO-66 for RhB, MNZ, and phenol reached 56.4 mg/g, 8.54 mg/g, and 2.06 mg/g, respectively. The breakthrough curves of MNZ adsorbed on UiO-66 are fitted for the Adams-Bohart and Yoon-Nelson models (R-2 > 0.95). The adsorption mechanisms were proposed according to the XPS characterizations. The UiO-66 shows good regeneration properties and high stability. The UiO-66 is an outstanding adsorbent that has potential application prospects in the continuous removal of pharmaceutical wastewater and dye wastewater in the environmental chemical engineering.