本文關(guān)鍵詞：稻草活性炭加速偶氮染料厭氧降解機理研究　出處：《蘇州科技大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 偶氮染料 稻草活性炭 氧化還原介體 電子轉(zhuǎn)移 機理

【摘要】：偶氮染料廢水因其具有成分復(fù)雜、毒害大、水量大等特點,在傳統(tǒng)的生物處理工藝中降解緩慢。碳材料具有發(fā)達的孔隙結(jié)構(gòu)和比表面積,且結(jié)構(gòu)中含有較多的官能團,使其具有優(yōu)異的物理和化學(xué)特性,一直都是廣大學(xué)者研究的熱點。本研究利用稻草秸稈制備了稻草活性炭(SAC)和改性稻草活性炭(SAC_M)兩種材料,有針對性的去除模擬染料廢水中的金橙G(OG)物質(zhì),研究了SAC和SAC_M在促進Na_2S化學(xué)降解OG和厭氧顆粒污泥生物降解OG過程中的影響因素以及其在UASB連續(xù)流工藝中實際應(yīng)用的可能性。首先通過表征手段對(NH_4)_2HPO_4作為活化劑制備的SAC和酚類物質(zhì)改性制得SAC_M的物理和化學(xué)性質(zhì)進行了分析,其中SEM結(jié)果表明,SAC和SAC_M均具有發(fā)達的孔隙結(jié)構(gòu)和比表面積,內(nèi)部孔隙大多是微孔結(jié)構(gòu),經(jīng)過對苯二酚改性后的SACHQ-1.0和苯鄰二酚改性后的SAC_(CT-1.0)比表面積明顯下降,而苯酚改性后的SAC_(CT-1.0)比表面積明顯上升;紅外光譜結(jié)果顯示了,SAC和SAC_M的結(jié)構(gòu)中有大量官能團存在,且酚類改性后的SAC_M結(jié)構(gòu)中的含氧官能團明顯增多;拉曼光譜結(jié)果表明SAC和SAC_M結(jié)構(gòu)中的無序碳原子或結(jié)構(gòu)缺陷較少;采用漂移法測定SAC_3與SAC_(PH-1.0)的pH_(pzc),得出SAC_3和SAC_(PH-1.0)的pH_(pzc)分別為2.62和2.21。然后研究了在OG的化學(xué)還原降解過程,發(fā)現(xiàn)單獨Na_2S對OG的還原降解效率較低,當(dāng)Na_2S濃度為10mmol/L、溫度為37℃和反應(yīng)初始pH為7.2的條件下,OG的脫色率僅為49%;其中反應(yīng)初始pH值對OG的降解影響較大,pH值在7.2~8.4范圍內(nèi),OG降解效果較好,pH8.4后,OG降解效果明顯變差,而pH值下降到6時,OG基本沒有降解。而投加SAC和SAC_M后Na_2S還原降解OG的速率顯著上升,且投加SAC_M的效果要好于SAC;在研究SAC促進Na_2S還原降解OG的過程中,發(fā)現(xiàn)30%(Wt)的(NH_4)_2HPO_4浸漬后制備的SAC_3效果最好,當(dāng)SAC_3投加量為0.3g/L、Na_2S濃度為10mmol/L、溫度為37℃和反應(yīng)初始pH為7.2的條件下,僅需90min后OG的脫色率就達到了100%,在SAC_3/Na_2S體系還原降解OG的過程中,OG的降解速率與SAC_3投加量、Na_2S濃度、溫度等成正相關(guān),與pH成負相關(guān)。在SAC_M促進Na_2S還原降解OG的過程中,發(fā)現(xiàn)苯酚濃度為1.0mmol/L時制備的SAC_(PH-1.0)效果最佳,當(dāng)SAC_(PH-1.0)投加量為0.3g/L、Na_2S濃度為10mmol/L、溫度為37℃和反應(yīng)初始pH為7.2的條件下,僅需30min后OG的脫色率就達到了100%,OG的降解速率與SACPH=1.0投加量、Na_2S濃度、溫度等成正相關(guān),與pH成負相關(guān)。通過TOC和UV-Vis光譜分析,得出SAC_3/Na_2S和SAC_(PH-1.0)/Na_2S體系中OG的礦化率分別為22.8%和34.2%,且OG結(jié)構(gòu)中的偶氮鍵和萘環(huán)結(jié)構(gòu)特征吸收峰隨著反應(yīng)的進行不斷下降,最后完全消失。最后研究了OG的生物降解過程,發(fā)現(xiàn)單獨AGS體系降解OG的效率較低,當(dāng)AGS濃度為30mmol/L、溫度為37℃和反應(yīng)初始pH為7.2的條件下,48h內(nèi)OG的脫色率僅為53.7%;遠小于投加SAC_3(0.3g/L)和SAC_(PH-1.0)(0.2g/L)后的72.2%和90%;SAC_3/Na_2S和SAC_(PH-1.0)/Na_2S體系對OG的降解速率與SAC_3和SAC_(PH-1.0)投加量、AGS濃度、溫度、營養(yǎng)液濃度成正相關(guān),與pH成負相關(guān)。在單獨UASB連續(xù)流系統(tǒng)中,當(dāng)進水OG的濃度提高到150mg/L時,60d后系統(tǒng)出水的OG濃度達到46mg/L左右;而投加碳材料后連續(xù)運行40天,SAC_3/UASB和SAC_(PH-1.0)/UASB連續(xù)流系統(tǒng)出水中OG濃度分別降低至25mg/L和16mg/L左右且保持穩(wěn)定;說明SAC_3和SAC_(PH-1.0)不僅在加速AGS降解OG的血清瓶實驗中效果優(yōu)異,而且在接近實際偶氮染料污水處理工藝的UASB連續(xù)流模型中,同樣發(fā)揮出較好的效果,使得這種環(huán)境友好型材料的實際應(yīng)用成為可能。綜上可知,SAC_3和SAC_(PH-1.0)作為氧化還原介體(Redox Mediators)具有更大的比表面積,且其結(jié)構(gòu)中的含氧官能團也較多,對Na_2S或者AGS與OG之間的電子轉(zhuǎn)移起到了加速的作用,SAC_3和SAC_(PH-1.0)作為RM轉(zhuǎn)移電子的速率主要跟自身物理和化學(xué)性質(zhì)有關(guān),可總結(jié)為一下兩點:(1)SAC_3和SAC_(PH-1.0)吸附性能;(2)SAC_3和SAC_(PH-1.0)表面含氧官能團含量。并通過GC-MS對OG化學(xué)和生物降解的產(chǎn)物和途徑進行了分析。
[Abstract]:Azo dye wastewater because of its complicated composition, high toxicity, high quantity, in the traditional biological treatment process. The slow degradation of carbon materials has developed the pore structure and surface area, and the functional groups contain more structure, which has excellent physical and chemical properties, has been the research focus of scholars this study. Straw activated carbon prepared by straw straw (SAC) and rice straw modified activated carbon (SAC_M) of two kinds of materials, targeted removal of dye wastewater in orange G (OG) material, study the influence factors of SAC and SAC_M in promoting Na_2S chemical degradation of OG and anaerobic granules sludgebiodegradation OG process and the possibility of its application in UASB continuous process. Firstly, through the characterization of (NH_4) _2HPO_4 as activator of SAC prepared and modified phenolic compounds prepared by physical and chemical properties of SAC_M The analysis results show that the SEM, SAC and SAC_M have developed pore structure and specific surface area, pore is mostly microporous structure after hydroquinone modified SACHQ-1.0 and benzene two adjacent phenol modified SAC_ (CT-1.0) significantly decreased the specific surface area, and phenol modified SAC_ (CT-1.0) significantly increased the specific surface area; infrared spectroscopy results show that, there are a large number of functional groups present structure of SAC and SAC_M, and the modified phenolic oxygen containing groups of SAC_M structure after the obviously increased; the Raman spectra results show that disordered carbon atoms or less structural defects SAC and SAC_M structure; Determination of SAC_3 and SAC_ by drift method (PH-1.0) pH_ (PZC), the SAC_3 and SAC_ (PH-1.0) pH_ (PZC) 2.62 and 2.21. respectively and then studied the reductive degradation process in OG chemistry, found that Na_2S alone reducing the degradation rate of OG is low, when the Na_2S concentration is 10mmol/L, temperature 搴︿負37鈩冨拰鍙嶅簲鍒濆pH涓，

本文編號：1356609