本文選題：過硫酸鹽　切入點：苯酚　出處：《內(nèi)蒙古科技大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：過硫酸鹽高級氧化技術(shù)由于能夠拓寬傳統(tǒng)Fenton反應(yīng)的p H適用范圍、減少含鐵污泥數(shù)量、提高氧化效率而受到廣泛關(guān)注。本論文使用熱、納米Fe_3O_4及天然鐵礦石三種方式活化過硫酸鈉,對比研究不同活化體系對含酚廢水的降解效果,考察不同方式活化過硫酸鹽高級氧化法降解含酚廢水的影響因素,對比不同活化方式降解污染物的機制,探究在最佳反應(yīng)條件下污染物的降解途徑。實驗結(jié)果表明,對于初始濃度為250 mg/L的苯酚廢水,熱活化過硫酸鈉體系的最佳反應(yīng)條件是50℃、過硫酸鈉:苯酚的物質(zhì)的量的比為60:1、初始p H為3,在此條件下苯酚的去除率為26.9%;由于去除率較低,因此考慮非均相活化體系,在納米Fe_3O_4活化體系中,當(dāng)過硫酸鈉與納米Fe_3O_4投加量均為12.5 m M,初始p H為6.18,溫度為50℃的條件下,苯酚去除率可以達(dá)到94.97%,降解過程中發(fā)生在納米Fe_3O_4表面的化學(xué)反應(yīng)起主導(dǎo)作用;鐵礦石活化體系的最佳反應(yīng)條件是過硫酸鈉與鐵礦石投加量均為0.4 g/L,初始p H為6.18,溫度為50℃,去除率可以達(dá)到89.96%,鐵礦石表面的化學(xué)反應(yīng)是主要的速度控制步驟。三種活化體系在酸性條件下起主要作用的活性自由基是硫酸根自由基(SO4-·),強堿性條件下起主要作用的活性自由基是羥基自由基(·OH)。對于固體催化劑納米Fe_3O_4和鐵礦石在重復(fù)利用四次后,對初始濃度250 mg/L的苯酚去除率分別為為85.73%和85.69%,表明兩種固體催化劑均具有較好的重復(fù)利用性和穩(wěn)定性。通過對比實驗可以看出,非均相體系活化過硫酸鹽具有更高的處理效率,能夠適應(yīng)更廣泛的p H值,在p H值為3~9范圍內(nèi),納米Fe_3O_4活化體系、天然鐵礦石活化體系反應(yīng)180 min后對苯酚廢水的去除率分別為86.65%~96.53%和82.61%~94.41%。通過紫外光譜分析得到苯酚在活化過硫酸鹽體系中降解的中間產(chǎn)物為對苯二酚、鄰苯二酚和丁烯化合物,表明過硫酸鹽高級氧化法可以有效降解廢水中的苯酚。
[Abstract]:Advanced persulfate oxidation technology has attracted wide attention due to its ability to broaden the pH range of traditional Fenton reactions, reduce the amount of ferric sludge and improve oxidation efficiency. Sodium persulfate was activated by nanometer Fe_3O_4 and natural iron ore. The effect of different activation systems on the degradation of phenol-containing wastewater was studied, and the factors affecting the degradation of phenol-containing wastewater by different ways of activated persulfate advanced oxidation were investigated. The mechanism of degradation of pollutants by different activation methods was compared, and the degradation pathway of pollutants was explored under the optimum reaction conditions. The experimental results showed that the initial concentration of phenol wastewater was 250 mg/L. The optimum reaction conditions for thermally activated sodium persulfate system are 50 鈩，

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