Optimization of the adsorption of erythromycin at environmentally relevant concentration by molecular imprinted polymer under different conditions

BACKGROUND

The presence of antibiotics in different environments poses a great risk to the environment and human health. Adsorption is an effective method to solve the problem. In our previous study, a molecularly imprinted polymer (MIP) with selective adsorption ability for erythromycin (ERY) at environmentally relevant concentration was prepared and characterized. However, the effect of different factors on the adsorption removal of ERY by MIP was not clear. In this study, the coprecipitation polymerization method was used to synthesize the MIP and the effects of temperature, pH, salinity and dissolved organic matter (DOM) on the adsorption of ERY by MIP were evaluated with batch experiments under different conditions.

RESULTS

The results showed the equilibrium adsorption capacity of MIP was increased from 814.62 to 1175.54 μg g⁻¹ when the temperature was increased from 283 to 303 K. The maximum adsorption capacity of MIP was 1061.12 μg g⁻¹ when the pH was 7.0. The presence of salinity would inhibit the adsorption process, in which the adsorption capacity of MIP was decreased from 1061.12 to 412.99 μg g⁻¹ when the salinity was increased to 20 g L⁻¹. Low concentration of DOM (<5 mg L⁻¹) promoted the adsorption of ERY significantly from 1061.12 to 1545.50 μg g⁻¹, while the adsorption capacity was slightly increased to 1812.50 μg g⁻¹ when the concentration of DOM reached 20 mg L⁻¹.

CONCLUSION

After optimization with orthogonal experiments, the adsorption capacity of MIP was increased from 334.10 to 458.05 μg g⁻¹ with real wastewater. © 2025 Society of Chemical Industry (SCI).