Removal of tetracycline hydrochloride (Tch) in simulated wastewater by zero-valent iron with ultrasonic irradiation (us-ziv)

Abstract

In this study, ultrasonic radiation zero-valent iron is used to remove tetracycline hydrochloride in aqueous solution. Zero-valent iron was characterized by SEM and XRD. The mechanism of tetracycline hydrochloride removal process by zero-valent iron was proposed. The effects of initial pH, zero-valent iron dosage, ultrasonic power and tetracycline hydrochloride concentration on the removal of tetracycline hydrochloride in the US-ZVI system were studied in detail. The US-ZVI system produces strong reducing agent ·H and new Fe2+, which can rapidly reduce tetracycline hydrochloride. The results show that with the US-ZVI system, a lower initial pH helps accelerate the removal of tetracycline hydrochloride. In addition, with the US-ZVI system, with the increase of initial zero-valent iron dosage can promote the degradation of tetracycline hydrochloride. However, compared with pH, ​the zero-valent iron dosage has less effect on the degradation of tetracycline hydrochloride. In addition, the ultrasonic wave improves the degradation of tetracycline hydrochloride by zero-valent iron. The higher the ultrasonic power, the better the removal effect of tetracycline hydrochloride. However, the initial tetracycline hydrochloride dosage has hardly affected on the degradation efficiency of tetracycline hydrochloride. And the improvement of degradation rate is mainly due to the synergy between US and ZVI. Then, the recycling experiments were carried out. Finally, according to liquid chromatography-mass spectrometry results, the degradation pathway of tetracycline hydrochloride was proposed.