Microwave-assisted iron oxide process for efficient removal of tetracycline.

Excess tetracycline produced by livestock and poultry breeding industry not only pollute the environment, but also enter the human body with the spread of the food chain, which will produce drug-resistant genes and threaten human health. In this paper, the adsoption of tetracycline from wastewater using iron oxide under microwave oxidation condition was explored. The effect of initial pollutant concentrations, the dosage of iron oxide, pH value, and temperature on the hybrid treatment process was investigated. Under the normal iron oxide and microwave oxidation conditions, when the dosage of iron oxide was 40 g/L and 30 g/L, pH was 10 and the temperature was 318 K, the removal rate of tetracycline was significantly improved. The adsorption of tetracycline by iron oxide under the two conditions conformed to the Freundlich isotherm model and pseudo-second-order dynamics model. In addition, the associated adsorption mechanism was unveiled. Under the microwave oxidation condition, the hot spot effect generated by the microwave oxidation effect would rapidly increase its surface temperature to form the active center and the electrostatic gravity to promote the reaction. The results indicated that microwave oxidation could promote the removal of antibiotics by iron oxide in livestock and poultry breeding wastewater.