本文選題：鄰苯二甲酸酯類物質(zhì) + 納米催化劑��； 參考：《山東建筑大學(xué)》2016年碩士論文

【摘要】：隨著城市化和工業(yè)化的不斷推進,經(jīng)市政排水管道收集的污水中除了含有大量常規(guī)污染物,另外多種微量或者痕量的有毒有害污染物也不斷增多,常規(guī)的水處理工藝并不能有效去除這些生物難降解的痕量污染物質(zhì),如內(nèi)分泌干擾物質(zhì),這不但加重了城市污水處理廠處理廢水的負擔(dān)和難度,也對環(huán)境安全和人體健康構(gòu)成了威脅。本研究選取六種常見的鄰苯二甲酸酯類物質(zhì)為目標污染物,應(yīng)用高級催化氧化技術(shù)對此種典型環(huán)境激素類物質(zhì)進行降解研究。采用水熱法合成納米a-Fe2O3作為催化劑,研究其聯(lián)合光助Fenton氧化技術(shù)對污染物的降解效果及影響因素,針對鄰苯二甲酸二甲酯(DMP)、鄰苯二甲酸二乙酯(DEP)、鄰苯二甲酸二丁酯(DBP)、鄰苯二甲酸丁芐酯(BBP)、鄰苯二甲酸(2-乙基己基)酯(DEHP)、鄰苯二甲酸二正辛酯(DnOP)六種鄰苯二甲酸酯類物質(zhì)尋找最優(yōu)降解條件；研究對實際城市污水處理廠高效沉淀池出水的應(yīng)用效果,并分析降解機理；通過分析光催化氧化降解DEP過程中的中間產(chǎn)物,探討了其降解歷程。主要研究內(nèi)容與結(jié)果如下：(1)建立了對實際水樣中低濃度的PAEs進行凈化和富集的固相萃取(SPE)預(yù)處理方法。應(yīng)用液相色譜-串聯(lián)質(zhì)譜(LC-MS-MS)聯(lián)用儀對水樣中的PAEs進行定性定量分析。使用氣相色譜-質(zhì)譜(GC-MS)儀建立了針對DEP光催化氧化降解過程的中間產(chǎn)物的分析檢測方法。(2)基于本課題組的前期的研究,本研究采用液相水熱合成法制成納米α-Fe2O3催化劑,尺寸均勻(約為70-80nm左右),呈球體和類球體狀。反應(yīng)時間9h以上,反應(yīng)溫度180%以上可得到純相的α-Fe2O3納米晶體。為了提高納米催化劑粉體的實用性,應(yīng)用活性炭為載體,通過燒結(jié)法得到α-Fe2O3-AC復(fù)合材料,活性炭負載催化劑避免了粉體催化劑在處理廢水過程中的流失、在光降解時粉體互相遮蔽,使光利用效率低以及處理后的回收等問題。(3)納米α-Fe2O3催化劑的應(yīng)用大大提高了光Fenton反應(yīng)的氧化效果。使用實驗室自制光催化反應(yīng)器,研究各種因素對非均相光助Fenton催化氧化降解含苯酚模擬廢水的影響,并探索最優(yōu)實驗條件的主要結(jié)果為：H2O2、Fe2+或納米催化劑α-Fe2O3投加量的適當增加,都會促進苯酚的降解,但過量的H2O2、Fe2+或α-Fe2O3,反而使降解效率降低或停滯。低濃度的苯酚廢水并沒有得到更高的降解率。α-Fe2O3-AC復(fù)合物投入量的適當增加,苯酚的降解率逐漸變大。隨著初始pH值的增大,降解率逐漸變小。研究結(jié)果表明：最佳反應(yīng)條件為：pH=3.0,H2O2初始濃度為20mM, Fe2+的初始濃度為0.5mM, α-Fe2O3投加量10mg·L-1,或者α-Fe2O3-AC復(fù)合物投加量為10g·L-1,對模擬苯酚廢水的去除率達98%以上。(4)六種PAEs在不同催化體系中的光催化降解效果不同,且遵循不同的降解機理。單獨UV光照、H202氧化、單獨Fenton反應(yīng)降解模擬PAEs水溶液的結(jié)果均不理想；使用UV/Fenton聯(lián)用工藝的降解率已經(jīng)大幅度提高；催化系統(tǒng)再增加活性炭后,六種PAEs的降解效率增加幅度并不大;而光催化系統(tǒng)將活性炭換成納米α-Fe2O3催化劑后,降解效率有較大幅度的提高,去除率均超過94%；而UV/Fenton/α-Fe2O3-AC工藝對PAEs的降解效率卻稍微有所降低。而與實驗室模擬水樣的降解實驗結(jié)果對比,真實水樣中六種PAEs的降解率均有所降低。不同PAEs的降解機理是有規(guī)律可循的,側(cè)鏈較短且簡單的,相對較容易去除,而側(cè)鏈較長且復(fù)雜,分子量較大的,相對難降解。不同的降解體系中,在α-Fe2O3表面上的催化降解過程遵循光催化機理,光生空穴會與催化劑表面的羥基族相互作用產(chǎn)生羥基自由基(·OH)。導(dǎo)帶上的光生電子可與溶解氧(O2)反應(yīng)生成活性氧物種O2-,O2-和·OH均具有強氧化性；而UV、H2O2、Fe2+和α-Fe2O3催化劑同時存在時,PAEs的催化降解存在兩種路徑：光催化機理和光-Fenton機理；α-Fe2O3-AC復(fù)合材料光催化降解PAEs的過程中,載體AC與催化劑α-Fe2O3之間的協(xié)同耦合作用,同時促進了鄰苯二甲酸酯的降解程度和速率。(5)在UV/Fenton/a-Fe203工藝的最優(yōu)條件下,以DEP為目標污染物,間接證明了·OH為降解DEP的主要因子,應(yīng)用GC-MS-MS檢測方法測定其降解的中間產(chǎn)物,主要有苯甲酸乙酯和鄰苯二甲酸二甲酯。分析DEP的降解歷程,DEP的光催化氧化降解主要發(fā)生在側(cè)鏈上,主要有兩種途徑：一是DEP的兩個側(cè)鏈末端的C原子被.OH進攻,使C-C鍵發(fā)生斷裂,形成DMP：另一降解途徑是-OH攻擊DEP苯環(huán)和側(cè)鏈酯基相連的a碳位,使C-C鍵發(fā)生斷裂,生成苯甲酸乙酯及其他小分子物質(zhì)。通過應(yīng)用納米α-Fe2O3催化劑及其與活性炭的復(fù)合物對六種典型鄰苯二甲酸酯類物質(zhì)的光催化氧化降解效果和機理的研究,為實際城市污水處理廠中鄰苯二甲酸酯類污染物質(zhì)的控制技術(shù)提供了理論指導(dǎo),具有重要的實際應(yīng)用價值。
[Abstract]:With the continuous advancement of urbanization and industrialization, the sewage collected by municipal drainage pipes contains a large number of conventional pollutants, and other trace or trace amounts of toxic and harmful pollutants are increasing. The conventional water treatment process can not effectively remove the trace contaminants, such as endocrine disrupting substances, which are difficult to reduce. This not only aggravates the burden and difficulty of wastewater treatment in urban sewage treatment plants, but also poses a threat to environmental safety and human health. In this study, six kinds of common phthalic acid esters were selected as the target pollutants, and advanced catalytic oxidation technology was used to study the degradation of the typical environmental irritable substances. As a catalyst, nano a-Fe2O3 was used as a catalyst to study the degradation effect and influence factors of the combined Fenton oxidation technology on pollutants, including two methyl phthalate (DMP), two ethyl ortho two formic acid (DEP), dibutyl phthalate (DBP), butyl benzyl ortho two formate (BBP), phthalic acid (2- ethyl hexyl) ester (DEHP), and phthalic acid two. Six ortho benzoate esters of ortho octyl (DnOP) were found to find the best degradation conditions. The application effect of the effluent from the high efficiency sedimentation tank of the actual municipal wastewater treatment plant was studied and the degradation mechanism was analyzed. The degradation process was discussed by analyzing the intermediate products in the process of photocatalytic oxidation degradation of DEP. The main contents and results were as follows: (1) A solid phase extraction (SPE) pretreatment method for the purification and enrichment of low concentration PAEs in the actual water samples was established. The qualitative and quantitative analysis of PAEs in water samples by liquid chromatography tandem mass spectrometry (LC-MS-MS) was applied to the analysis of the intermediate products of the photocatalytic oxidation degradation of DEP by gas chromatography-mass spectrometry (GC-MS). (2) (2) based on the previous study of this research group, this study uses liquid hydrothermal synthesis method to form a nano -Fe2O3 catalyst, with a uniform size (about 70-80nm), spherical and spheroid. The reaction time is above 9h and the reaction temperature is above 180%. The pure phase alpha -Fe2O3 nanocrystalline can be obtained. Using the active carbon as the carrier, a -Fe2O3-AC composite is obtained by sintering. The activated carbon supported catalyst avoids the loss of the powder catalyst in the process of wastewater treatment. In the light degradation, the powder is shielded from each other, and the use efficiency is low and the recovery after treatment. (3) the application of nano -Fe2O3 catalyst has been greatly improved. The effects of various factors on the degradation of simulated wastewater containing phenol by heterogeneous photoassisted Fenton catalytic oxidation were studied by a laboratory self-made photocatalytic reactor, and the main results of the optimal experimental conditions were the appropriate increase in the dosage of H2O2, Fe2+ or nano catalyst alpha -Fe2O3, which would promote the degradation of phenol. However, excessive H2O2, Fe2+ or alpha -Fe2O3 reduced the degradation efficiency or stagnated. The low concentration of phenol wastewater did not get a higher degradation rate. The degradation rate of phenol increased gradually with the appropriate increase of the input of alpha -Fe2O3-AC complex. The degradation rate gradually became smaller with the initial pH value increasing. The results showed that the optimum reaction condition was p The initial concentration of H=3.0, H2O2 is 20mM, the initial concentration of Fe2+ is 0.5mM, the dosage of alpha -Fe2O3 is 10mg. L-1, or the dosage of alpha -Fe2O3-AC complex is 10g L-1, and the removal rate of the simulated phenol wastewater is above 98%. (4) the photocatalytic degradation effect of six kinds of PAEs in different catalytic systems is different and follows different degradation mechanisms. The results of degradation of simulated PAEs aqueous solution by the single Fenton reaction were not ideal, and the degradation rate of the combined use of UV/Fenton was greatly improved, and the degradation efficiency of the six PAEs was not greatly increased after the catalytic system was added to the activated carbon, and the photocatalytic system changed the activated carbon to the nano - -Fe2O3 catalyst. The removal efficiency of the UV/Fenton/ alpha -Fe2O3-AC process is slightly lower than 94%, while the degradation efficiency of PAEs is slightly reduced. Compared with the experimental results of laboratory simulated water samples, the degradation rates of six kinds of PAEs in real water samples are reduced. The degradation mechanism of different PAEs is regular, and the side chain is shorter and simpler. It is relatively easy to remove, while the side chain is longer and complex, and the molecular weight is relatively difficult to degrade. In the different degradation systems, the catalytic degradation process on the surface of the alpha -Fe2O3 follows the photocatalytic mechanism, the photogenerated cavitation can produce hydroxyl radical (. OH) with the hydroxyl group on the catalyst surface. The photogenerated electrons on the guide band and the dissolved oxygen (O2) can be found. The reactive oxygen species O2-, O2- and OH have strong oxidation, while UV, H2O2, Fe2+ and alpha -Fe2O3 exist at the same time, there are two pathways in the catalytic degradation of PAEs: photocatalytic mechanism and optical -Fenton mechanism; in the process of photocatalytic degradation of alpha -Fe2O3-AC composite, the synergistic coupling between carrier AC and catalyst alpha At the same time, the degradation degree and rate of phthalate two formate were promoted. (5) under the optimal condition of UV/Fenton/a-Fe203 process, DEP was used as the target pollutant, and OH was indirectly proved to be the main factor of degradation of DEP. The intermediate products of degradation were determined by GC-MS-MS detection method, including ethyl benzoate and two methyl phthalic acid two formate. Analysis of the degradation process of DEP, the photocatalytic oxidation degradation of DEP mainly occurs on the side chain, and there are two main ways: one is that the C atom at the end of the two side chain of DEP is attacked by.OH, which causes the C-C bond to break up and form DMP. The other degradation pathway is -OH attacking the a carbon position connected by the DEP benzene ring and the side chain ester group, making the C-C bond broken and producing ethyl benzoate. The study on the photocatalytic oxidation degradation effect and mechanism of six typical phthalic acid esters by using nano -Fe2O3 catalyst and its complex with activated carbon has provided theoretical guidance for the control technology of phthalic acid esters in actual municipal wastewater treatment plant. Practical application value.

【學(xué)位授予單位】：山東建筑大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2016
【分類號】：X703

【參考文獻】

相關(guān)期刊論文 前7條

1 金葉;章宏梓;吳禮光;周志軍;陳歡林;;納濾膜對鄰苯二甲酸酯的動態(tài)吸附行為及截留特性[J];水處理技術(shù);2011年12期

2 趙玲;劉敏;尹平河;吳楚萍;金波;;鄰苯二甲酸二甲酯的光催化降解機理[J];環(huán)境工程學(xué)報;2011年06期

3 孟慶華;朱亦仁;顧紹玲;屠樹江;張倩萍;;納米α-Fe_2O_3合成及光催化法處理染料中間體廢水[J];無機鹽工業(yè);2011年01期

4 陳喜娣;蔡啟舟;尹荔松;何劍;;納米α-Fe_2O_3光催化劑的研究與應(yīng)用進展[J];材料導(dǎo)報;2010年21期

5 姚淑華;賈永鋒;汪國慶;石中亮;;活性炭負載Fe(Ⅲ)吸附劑去除飲用水中的As(Ⅴ)[J];過程工程學(xué)報;2009年02期

6 費學(xué)寧;姜遠光;呂巖;張?zhí)煊?;環(huán)境激素鄰苯二甲酸二丁酯的光催化降解機理探討[J];應(yīng)用化學(xué);2006年01期

7 胡曉宇,張克榮,孫俊紅,吳德生;中國環(huán)境中鄰苯二甲酸酯類化合物污染的研究[J];中國衛(wèi)生檢驗雜志;2003年01期

相關(guān)博士學(xué)位論文 前2條

1 林興桃;鄰苯二甲酸酯及其代謝物分析方法研究及暴露評價[D];北京工業(yè)大學(xué);2012年

2 曾涑源;α-Fe_2O_3納米結(jié)構(gòu)的液相合成及性能表征[D];中國科學(xué)技術(shù)大學(xué);2008年

相關(guān)碩士學(xué)位論文 前5條

1 曾燕艷;城市尾水中低濃度鄰苯二甲酸酯（PAEs）的降解研究[D];華南理工大學(xué);2012年

2 陶波;α-Fe_2O_3納米材料的可控合成及應(yīng)用研究[D];安徽師范大學(xué);2012年

3 李巖;納米H_3PW_（12）O_（40）/TiO_2復(fù)合材料光催化降解水中酞酸酯類化合物的研究[D];東北師范大學(xué);2006年

4 楊開林;微波+Fenton試劑+活性炭處理鄰苯二甲酸酯的研究[D];重慶大學(xué);2006年

5 張科杰;Fenton試劑處理酸性玫瑰紅B染色廢水的試驗研究[D];天津大學(xué);2004年

，

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