本文選題：·OH自由基 + 電化學(xué)氧化��； 參考：《西安建筑科技大學(xué)》2015年碩士論文

【摘要】：隨著我國工業(yè)的迅猛發(fā)展,由工業(yè)廢水排放引發(fā)的水污染問題日漸引起人們的廣泛關(guān)注。其中生物難降解有機廢水由于處理難度大,采用傳統(tǒng)的方法很難達(dá)到滿意的效果,而電化學(xué)氧化技術(shù)是一種新型綠色的生物難降解有機廢水處理技術(shù),具有兼容性好、處理效率佳、不易產(chǎn)生二次污染、操作簡便、易于實現(xiàn)自動化等優(yōu)勢,近年來成為國內(nèi)外研究者廣泛關(guān)注的熱點領(lǐng)域。電化學(xué)氧化技術(shù)主要通過產(chǎn)生強氧化劑——羥基自由基(·OH),使得有機污染物被氧化降解。因此,對·OH自由基的生成及影響規(guī)律進(jìn)行檢測,對于優(yōu)化反應(yīng)條件和反應(yīng)器設(shè)計,深入研究有機物的電化學(xué)氧化機理具有重要的意義。本論文采用電沉積法制備出了以[emim]BF4離子液體為添加劑的高性能Ti/Pb O2電極,通過SEM、XRD、苯酚模擬廢水降解實驗和強化壽命測試等方法對自制Ti/Pb O2電極的表面形貌、電極活性及穩(wěn)定性進(jìn)行了表征。研究結(jié)果顯示:50℃時添加50mg/L[emim]BF4離子液體制備得到的電極結(jié)晶良好,沉積層均勻致密,且電極活性較高、穩(wěn)定性較好,可以用作電化學(xué)氧化體系中·OH自由基的產(chǎn)生電極。使用高效液相色譜-紫外檢測技術(shù)(HPLC-UV),分別以水楊酸(SA)和4-羥基苯甲酸(4-HBA)為捕捉劑測定電化學(xué)氧化體系中生成的·OH自由基。色譜分離條件為:柱溫為30℃、流動相為40%(v/v)甲醇:60%(v/v)超純水、流速為1m L/min、每次進(jìn)樣20μL。研究結(jié)果顯示,SA和4-HBA分別與·OH自由基的電化學(xué)氧化反應(yīng)均符合一級反應(yīng)動力學(xué),反應(yīng)速率常數(shù)分別為2.1833×10-4s-1和1.3500×10-4s-1;SA的捕捉能力為4-HBA的3倍,相較而言SA具有更高的靈敏度。因此SA為更適宜本研究體系的捕捉劑。以SA為捕捉劑,從電解液性質(zhì)、電解反應(yīng)器條件和外部能量輸入等角度探尋不同的電化學(xué)氧化條件對·OH自由基生成的影響規(guī)律。結(jié)果表明:隨著電解液p H值的增大,·OH自由基的生成速率逐步增加,堿性條件下更有利于·OH自由基的生成;電流密度的增加使得·OH自由基生成速率逐漸增加,當(dāng)電流密度大于10m A/cm2時,·OH自由基生成速率的增加趨勢逐漸平緩;使用較低濃度范圍的支持電解質(zhì),·OH自由基的生成速率先增大后減小,0.03mol/L無水Na2SO4更適合本研究體系;無機抑制劑對·OH自由基生成的抑制作用強于有機抑制劑,且Na2CO3對·OH自由基生成的抑制作用最強;隨著極板間距的增加,·OH自由基生成速率先增加后減小,當(dāng)極板間距為3cm時·OH自由基生成速率最高;陰極材料為不銹鋼時可實現(xiàn)節(jié)約能耗的目標(biāo)。
[Abstract]:With the rapid development of industry in China, water pollution caused by industrial wastewater discharge has attracted more and more attention. Because of the difficulty in the treatment of biodegradable organic wastewater, it is difficult to achieve satisfactory results by using traditional methods. However, electrochemical oxidation is a new type of green biodegradable organic wastewater treatment technology, which has good compatibility. In recent years, the advantages of high efficiency, easy to produce secondary pollution, simple operation and easy to realize automation have become the focus of attention of researchers at home and abroad. Electrochemical oxidation technology mainly produces strong oxidant-hydroxyl radical (OHN), which results in the oxidative degradation of organic pollutants. Therefore, the detection of the formation and influence of OH radicals is of great significance for optimizing the reaction conditions and reactor design and studying the electrochemical oxidation mechanism of organic compounds. In this paper, the high performance Ti- / PbO2 electrode with [emim] BF4 ionic liquid as additive was prepared by electrodeposition method. The surface morphology of self-made Ti / PbO2 electrode was studied by means of SEMX XRD, phenol simulated wastewater degradation experiment and enhanced lifetime test. The electrode activity and stability were characterized. The results show that the electrode prepared by adding 50mg / L [emim] BF4 ionic liquid at 50 鈩，

本文編號：2037007