MW-Fe0/H2O2体系预处理垃圾渗滤液浓缩液有机物

为探究MW-Fe⁰/H₂O₂类芬顿反应对渗滤液浓缩液的效能与机理，探讨了废水初始pH值、Fe⁰投加量、H₂O₂投加量、MW功率和反应时间等影响因素对有机物去除效果，通过类比实验对MW-Fe⁰/H₂O₂体系处理渗滤液浓缩液中MW辐射的反应机理进行研究，并采用了SEM和XRD技术对反应前后的Fe⁰物相变化及催化机理进行了探究.结果表明，在初始pH值为3.0，Fe⁰投加量0.5g/L，H₂O₂投加量20mL/L，MW功率400W，反应时间14min时，其COD、UV₂₅₄以及色度（CN）的去除率分别为58.70%、85.69%和88.30%.类芬顿类比实验说明MW-Fe⁰/H₂O₂体系处理后具有较高的有机物去除率和可生化性；紫外-可见光谱表明，Fenton和MW-Fe⁰/H₂O₂类芬顿反应均能使废水中有机物的芳香性程度、分子量和缩合度大幅度降低，但MW-Fe⁰/H₂O₂类芬顿反应优于其他反应过程；三维荧光光谱显示，MW-Fe⁰/H₂O₂类芬顿反应能使渗滤液浓缩液中荧光峰峰位蓝移，说明废水的腐殖质缩合度减小，且分子量大幅降低.与此同时，Fe⁰在反应过程中，表面由光滑变得粗糙且被腐蚀为Fe₃O₄和FeOOH等物质.MW-Fe⁰/H₂O₂类芬顿反应的主要机理为芬顿反应及铁氧化物-H₂O₂非均相芬顿反应的高级氧化作用、铁基胶体对有机物的吸附沉淀，而MW的热效应和非热效应加速了以上作用的进行，从而能对渗滤液浓缩液中有机污染物进行快速去除.

Enhanced degradation of refractory organics in leachate concentrates by Fe0/H2O2 coupled with microwave irradiation

To study the effect and mechanism of MW-Fe⁰/H₂O₂ Fenton-like process on concentrated leachate, the effects of initial pH, Fe⁰ dosage, H₂O₂ dosage, MW power and reaction time on the removal of organic substances were investigated. The phase change of Fe⁰ before and after reaction and its catalytic mechanism were investigated by SEM micrograph and XRD spectra. Results showed that the removal efficiencies of COD, UV₂₅₄ and CN were 58.70%, 85.69% and 88.30% at initial pH of 3.0, Fe⁰ dosage of 0.5g/L, H₂O₂ dosage of 20mL/L, MW power of 400W and reaction time of 14min. Comparison of different Fenton-like process indicated that a higher removal efficiency of organic substances and a greater biodegradability were achieved after MW-Fe⁰/H₂O₂ Fenton-like process. UV-Vis spectra illustrated that both Fenton and MW-Fe⁰/H₂O₂ processes can significantly decrease the aromaticity degree, molecular weight and condensation degree of organic substances in wastewater, however, MW-Fe⁰/H₂O₂ process was the most efficient. 3D-EEM spectrum demonstrated that the fluorescence peak of concentrated leachate occurred blue-shift in MW-Fe⁰/H₂O₂ process, further indicating that condensation degree of humic substances declined and molecular weight remarkably decreased. After MW-Fe⁰/H₂O₂ process, the surface of Fe⁰ changed from smooth to rough and the material was corroded as Fe₃O₄ and FeOOH, indicating that the mechanism of MW-Fe⁰/H₂O₂ process was Fenton reaction and advanced oxidation effect of heterogeneous Fenton reaction between iron oxide and H₂O₂, adsorption and precipitation effects of iron based colloid on organic substances. Moreover, thermal and non-thermal effects of MW accelerated the actions mentioned above. Thereby, fast removal of organic pollutants in concentrated leachate was achieved.