【摘要】 为了探讨微波（MW）/铁碳（Fe-C）/H₂O₂类芬顿反应对填埋场渗滤液膜滤浓缩液（简称"渗滤液浓缩液"）中难降解有机物,系统研究了双氧水投量、Fe-C投量、初始pH值、微波输出功率和反应时间对浓缩液中有机污染物的去除规律,通过类比实验研究了MW/Fe-C/H₂O₂体系的反应协同作用;此外,采用紫外-可见和三维荧光光谱表征了浓缩液中溶解性有机物的分子结构变化;最后,利用SEM-EDS和XRD等表征对反应前后的Fe-C材料的催化机理进行了解析.结果表明,在双氧水投量为10 mL·L^-1,Fe-C投量0.8 g·L^-1,初始pH值为3,微波输出功率为450 W,反应时间为12 min时,其COD、腐殖质和色度的去除率达到了70.06%、94.61%和98.86%.与此同时,控制实验表明MW/Fe-C/H₂O₂具有较强的协同作用,且对有机物的降解效果远好于其他体系.经过MW/Fe-C/H₂O₂体系处理后,浓缩液中溶解性有机物的芳香性程度和腐殖质缩合度逐渐降低,并且腐殖质等大分子难降解有机物大幅去除,可生化性（BOD/COD值）也大幅提升.一方面,Fe-C材料包含了多种铁基氧化物等活性物质可与H₂O₂形成非均相芬顿反应;另一方面,在酸性条件下铁缓释淋滤产生的铁离子会与H₂O₂形成芬顿反应.并且,微波辐射作用可一定程度上强化上述过程,从而加速了有机物的去除.因此,MW/Fe-C/H₂O₂体系能够快速高效的对渗滤液浓缩液进行预处理,研究为高浓度有机废水的处理提供了借鉴.更多还原

【Abstract】 In this study, the Fe-C catalyzed H₂O₂ process enhanced by microwave radiation（MW/Fe-C/H₂O₂ process） was applied to the pre-treatment of refractory organics in landfill leachate membrane concentrates. The effects of H₂O₂ dosage, Fe-C dosage, initial pH, and microwave intensity on refractory organics removals were systematically investigated. In addition, the synergetic effect of MW/Fe-C/H₂O₂ process was investigated. Transformation of dissolved organic matter was explored by UV-Vis and 3 D-EEM analysis. Finally, the material（Fe-C） were characterized by SEM-EDS and XRD in order to explore the catalysis mechanism of MW/Fe-C/H₂O₂ process. Results show that the removal rates of COD, humic substances（indicated by absorbance at 254 nm）, and color number（CN） were 70.06%, 94.61%, and 98.86%, respectively, under conditions of H₂O₂ dose=10 mL·L^-1, Fe-C dose=0.8 g·L^-1, initial pH=3, microwave power=450 W, and reaction time=12 min. Moreover, the MW/Fe-C/H₂O₂ process exhibited a significant synergetic effect, and the treatment efficacy of MW/Fe-C/H₂O₂ process was much better than that of any other processes performed in this study. After the treatment of MW/Fe-C/H₂O₂ process, the aromatics and humic substances in dissolved organic matter were gradually reduced in membrane concentrates. Meanwhile, the biodegradability（BOD/COD ratio） was improved significantly. According to SEM-EDS and XRD analysis results, the treatment efficacy of MW/Fe-C/H₂O₂ process can be attributed to several aspects: ① Fe-C material contained a variety of active matters, such as iron-based oxidants, that can react with H₂O₂ to form heterogeneous Fenton system; ②the acidic ambient accelerated iron leaching, therefore homogeneous Fenton system was formed by Fe²⁺ and H₂O₂; and ③microwave radiation promoted the reaction kinetics,thus enhanced the removal of organic pollutants. In conclusion, MW/Fe-C/H₂O₂ process was efficient in the pre-treatment of refractory organics in membrane concentrates from landfill leachate. This study aimed to provide a technical reference for the treatment of high organic wastewater.更多还原