微波诱导催化氧化水钠锰矿降解亚甲基蓝

摘要

系统研究了水钠锰矿在微波的作用下催化降解亚甲基蓝（MB）的效果和影响因素，并结合X射线衍射技术（XRD）、傅里叶变换红外光谱分析（FTIR）、紫外-可见分光光谱（Uv-vis）等技术，深入探讨了该反应体系的作用机理。结果表明：水钠锰矿（δ-MnO2型锰矿物）是一种优良的微波催化剂，在功率400 W和酸性的条件下，微波辅助0.1 g水钠锰矿催化降解50 mL浓度为500 mg/L的亚甲基蓝30 min再静置5 h后，去除率可达到99.7%；体系的作用机理是，微波诱导氧化水钠锰矿，可产生活性氧化物MnO4−，进而将体系中的亚甲基蓝氧化分解。%The influence of reaction time,system pH and dosage of catalyst on degradation of methylene blue in water by microwave induced oxidation of Birrnessite was studied. Reaction mechanism was determined based on powder X-ray diffraction (XRD),infrared spectroscopy (IR) and UV-visible spectroscopy (Uv-vis). The optimum reaction conditions were:400 W microwave irradiatione of 50 mL 500 mg/L methylene blue solution with 0.1 g Birnessite for 30 min and static adsorption for 5h,achieving degradation efficiency of 99.7%. Birnessite was oxidized to form reactive MnO4− by microwave irradiation,which degraded MB into small molecules.