花球状Fe3O4/MoS2活化过一硫酸盐氧化去除环丙沙星

Flower-like spherical Fe3O4 / MoS2 catalyst activated PMS for efficient removal of ciprofloxacin

摘要:

采用水热法将纳米颗粒Fe3O4负载于花球状MoS2，制备出花球状Fe3O4/MoS2复合催化剂。通过SEM、XRD、XPS和VSM等手段对Fe3O4/MoS2进行表征，并考察了花球状Fe3O4/MoS2活化过一硫酸盐(PMS)对环丙沙星(CIP)去除性能。考察了不同体系、pH、Fe3O4/MoS2投加量、PMS投加量、CIP初始浓度和常见阴离子及腐植酸对Fe3O4/MoS2/PMS体系去除 CIP的影响，并探究了花球状Fe3O4/MoS2复合催化剂的循环稳定性。结果表明，在30 ℃、催化剂投加量0.2 g/L、PMS投加量0.25 mmol/L、CIP浓度5 mg/L的条件下，20 min内CIP的去除率可达96.1%，且在较宽的pH范围内（3.0~9.0）该体系仍具有较高的去除率。催化剂经三次循环试验后仍能对CIP有90.27%的去除率。自由基淬灭试验和EPR测试表明，Fe3O4/MoS2活化PMS去除CIP的机制包括自由基途径(?SO4–和?OH)和非自由基途径(1O2)，其主要活性物质为1O2。本研究为活化PMS处理水中抗生素提供了一定的理论依据和技术支撑。

Abstract:

Nano-Fe3O4 was loaded on globular MoS2 by hydrothermal method to prepare globular Fe3O4/MoS2 composite catalyst. Fe3O4/MoS2 was characterized by SEM, XRD, XPS and VSM, and the removal performance of ciprofloxacin (CIP) by flower globular Fe3O4/MoS2 activated persulfate (PMS) was investigated. The effects of different systems, pH, Fe3O4/MoS2 dosage, PMS dosage, initial CIP concentration, common anions and humic acid on CIP removal in Fe3O4/MoS2/PMS system were investigated, and the cycle stability of flower ball Fe3O4/MoS2 composite catalyst was investigated. The results show that under the conditions of 30℃, 0.2 g/L catalyst dosage,0.25g / L PMS dosage and 5 mg/L CIP concentration, the removal rate of CIP can reach 96.1% within 20 min, and the system still has a high removal rate in a wide range of pH (3.0~9.0). After three cycles, the catalyst can still remove 90.27% of CIP. Free radical quenching test and EPR test showed that the mechanism of CIP removal by Fe3O4/MoS2 activated PMS included free radical pathway (?SO4- and ?OH) and non-free radical pathway (1O2), and the main active substance was 1O2. This study provides some theoretical basis and technical support for activating PMS to treat antibiotics in water.