Sponge-loaded biogenic manganese oxide (BMO@Sponge) activated peroxymonosulfate for tetracycline degradation in wastewater: Efficacy and mechanism

In this study, sponge-loaded biogenic manganese oxide (BMO@Sponge) biomaterials were fabricated to activate peroxymonosulfate (PMS) for efficient antibiotic degradation. The BMO@Sponge preparation conditions were optimized, and the effects of the reaction conditions in the BMO@Sponge treatment system on the activation of PMS for the degradation of representative antibiotics (tetracycline hydrochloride, TC) were investigated. The degradation path and degradation mechanism of TC during BMO@Sponge/PMS were proposed. BMO@Sponge was successfully prepared via a biogenic Mn oxidation process. After the sample was cultured for 3 days and when the concentration of the sponge carrier was 20 pieces/L and the initial concentration of Mn(II) was 20 mg/L, the BMO content on the sponge carrier was 0.62 mg/piece. After 180 min of reaction, the TC degradation efficiency reached 93.54 % when the pH was 9, the PMS concentration was 0.2 g/L, and the BMO@Sponge dosage was 20 pieces/L. Free radical quenching and EPR identification experiments confirmed that SO 4 ·- and 1 O 2 were the main active substances for TC degradation in the BMO@Sponge/PMS system. The acute toxicity analysis indicated that the concentrations of most of the intermediate products were much lower than those of TC. Based on the cyclic stability tests, BMO@Sponge had good chemical stability. In the case of actual antibiotic wastewater, the removal efficiencies were 84.26 % for COD, 72.95 % for NH 3 -N, and 45.62 % for TOC in the BMO@Sponge/PMS system. This study provide an alternative method for the effective treatment of antibiotic wastewater. • BMO@Sponge was fabricated and used to activate PMS for TC degradation. • SO 4 ·- and 1 O 2 are the main active substances for TC degradation. • The toxicity of most of the intermediates are was much lower than that of TC. • The removal efficiency of COD reached 84.26 % in actual antibiotic wastewater.