本文關鍵詞：納米水合二氧化錳氧化水中典型有機污染物的效能研究　出處：《哈爾濱工業(yè)大學》2013年博士論文　論文類型：學位論文

  更多相關文章： 納米水合二氧化錳 脫鹵 磺胺 溴酚 凝聚 復合污染

【摘要】：錳元素是自然界中豐度較高的金屬元素之一，它的氧化物不僅參與了自然環(huán)境中許多有機、無機成分的遷移轉化，還在水質凈化過程中發(fā)揮著重要作用。在水處理中，二氧化錳一般通過高錳酸鹽的氧化還原原位產生，它不僅對高錳酸鹽的氧化具有重要意義，自身還具有許多重要的除污染特性�；前泛弯宸宇惢衔镌谒w中頻繁檢出，兩類化合物與二氧化錳反應的特征官能團不同，分別為芳胺基和酚羥基。本文通過硫代硫酸鈉還原高錳酸鉀制得納米水合二氧化錳（nHMO），模擬水處理中原位產生的二氧化錳，進而研究其對目標物的催化氧化特性。 本文中制得的nHMO粒徑分布在24.4~91.2nm之間，能夠穩(wěn)定存在40天以上。不同制備濃度、溫度和混合方式對產生的nHMO的粒徑均有影響，從而影響它的氧化活性。對混方式制得的nHMO比滴加方式制得的nHMO平均粒徑小18.41nm。當pH為7.3時，前者氧化SMZ的效率要高出后者28%。制備液濃度越低、溫度越高，制得的nHMO的平均粒徑越小，它的氧化活性越高。 為了考察nHMO的氧化活性，本文選取了磺胺二甲嘧啶（SMZ）、磺胺甲噻唑（SMZO）、磺胺甲VA唑（SMX）三種具有芳胺結構的藥物進行研究。nHMO氧化三種磺胺的能力依次為：SMZSMXSMZO。相比其它常見的二價陽離子，錳離子對nHMO的氧化抑制最明顯，當pH為6.0時，5μM錳離子就使SMZ的去除率下降22%。低濃度的磷酸根對SMZ的去除率影響較小，但是腐殖酸以及高濃度的磷酸根都表現出一定的抑制作用。nHMO氧化三種有機物的動力學曲線均不符合假一級動力學，反應后期存在明顯的自抑制現象。本文通過引入兩個動力學參數Sr和k，分別表示二氧化錳氧化有機物的活性位點數和基于該值的反應速率常數，建立了nHMO氧化SMZ的動力學模型。該模型能夠很好的擬合整個氧化過程，其中，，隨著SMZ初始濃度的增加，Sr值增加，k值減小；隨著nHMO濃度的增加，Sr值增加，k值增加；pH值的增加導致Sr值和k值均降低。 為了研究nHMO氧化鹵代酚類有機物過程中的脫鹵現象，本文選取了三種溴酚進行了研究。nHMO氧化三種溴酚的能力依次為：4-溴酚（4-BrP）2-溴酚（2-BrP）3-溴酚（3-BrP），氧化過程中的脫溴能力也遵循相同的次序。假一級條件下，nHMO氧化4-BrP的反應速率常數隨著溴酚濃度的增加保持不變，表明表面絡合物的電子轉移是該氧化過程中的速控步驟。nHMO氧化溴酚過程中的脫溴指數（DN）隨著pH的升高而逐漸減小，表明nHMO氧化溴酚的過程不僅僅遵循有機自由基耦合的機理。氮氣曝氣對溴酚的氧化及溴離子的釋放均有一定的抑制作用，且pH5.0時的抑制效果比pH4.0時更明顯。nHMO氧化溴酚的過程中，nHMO顆粒粒徑不斷增大，溴酚和nHMO初始濃度越大、pH越低，顆粒粒徑增大的幅度越大。氧化過程中產生的錳離子大部分吸附在二氧化錳表面，溶液中錳離子濃度很低。 鑒于nHMO的氧化活性和它的納米粒徑相關，本文還研究了nHMO氧化過程中的凝聚現象。錳離子引發(fā)的nHMO凝聚具有較低的臨界濃度，在10-5M級別。隨著pH值的升高，相同錳離子濃度引起的凝聚速率增大，因而引起擴散凝聚的臨界濃度降低。nHMO氧化有機物過程中的凝聚速率主要取決于與有機物的反應速率，pH值升高，氧化速率降低，凝聚速率減慢。nHMO的氧化凝聚對氧化效能的影響很大，投加少量高錳酸鉀可以有效控制nHMO氧化過程中的凝聚。nHMO/少量高錳酸鉀組合體系氧化初始濃度為2.5~16.8μM的雙酚A（BPA）時，自抑制現象消失，其假一級速率常數分別與nHMO單獨氧化時初始階段的速率常數一致，表明高錳酸鉀在該體系中主要起氧化錳離子和維持nHMO納米粒徑的作用；而在氧化4-硝基酚（4-NP）時，高錳酸鉀主要參與表面絡合物的電子轉移過程，從而強化4-NP的氧化去除，該組合體系主要表現為二氧化錳催化高錳酸鉀氧化4-NP。 二氧化錳對高錳酸鉀氧化除污染具有非常重要的催化作用，本文選取了雙鍵類污染物卡馬西平（CMZ）以及酚類污染物雙酚A（BPA）、苯酚（Phen）、2-氯酚（2-CP）、2,4-二氯酚（2,4-DCP）、2,4,6-三氯酚（2,4,6-TCP）等目標物，研究了高錳酸鉀氧化以兩種有機物形成的復合污染過程中nHMO和其它中間態(tài)錳物種的重要作用。在弱酸性條件下，CMZ能夠促進Phen的氧化去除而自身不受影響；酚類化合物的氧化去除則表現為互相促進，且反應慢的酚的氧化去除受到的促進更大，nHMO的催化作用是造成這些現象的主導原因。弱堿性條件下，CMZ和Phen復合時，二者的氧化去除均不受影響；酚類污染物之間復合時，表現為與高錳酸鉀反應速率常數較低的酚的氧化去除受到抑制，而反應速率常數較大的酚的氧化去除受到的影響很小。競爭動力學的研究表明，這種抑制作用主要是兩種酚類污染物競爭了體系中除高錳酸鉀及nHMO以外的其它氧化活性物種所致。由于CMZ的氧化機制和Phen不同，二者不存在競爭作用，因而二者的共存對各自的氧化均不構成影響。
[Abstract]:Manganese is one of the metal elements in high abundance in nature, it is not only involved in oxides in natural environment of many organic, inorganic composition of migration transformation, play an important role in the process of water purification. Still in water treatment, the manganese dioxide by permanganate oxidation and reduction of in situ generated, it not only has important significance to permanganate oxidation, also has many important characteristics. In addition to pollution of sulfonamides and bromophenol compounds are frequently detected in water medium, two characteristic functional group compounds and manganese dioxide reaction were different, aromatic amino and phenolic hydroxyl. The sodium thiosulfate reduction Potassium Permanganate nanoscale hydrous manganese dioxide (nHMO), manganese dioxide produced in situ simulated water treatment the object of the research of catalytic oxidation properties.
This paper prepared nHMO particle size distribution between 24.4~91.2nm, can be stable in more than 40 days. Prepared by different concentration, influence of temperature and mixing methods on nHMO size were, thus affecting its reactivity. The mixing mode of the prepared nHMO than dropping made nHMO average particle size. Small 18.41nm. when pH is 7.3, the efficiency of oxidation of SMZ is up to the preparation of 28%. solution concentration is low, the higher the temperature, the average particle size of nHMO was smaller, its higher oxidation activity.
In order to study the activity of oxidation of nHMO, this paper selects the sulfamethazine (SMZ), sulfamethoxazole (SMZO), sulfamethoxazole (SMX) with VA three with aromatic amine structure of drug.NHMO oxidation of three sulfonamides were SMZSMXSMZO. compared with the other two common divalent cations, oxidation of manganese ion on nHMO the most obvious inhibition, when pH is 6, 5 mu makes M manganese ions decreased the removal rate of SMZ 22%. phosphate in low concentration has little effect on the removal rate of SMZ, but high concentration of humic acid and phosphate showed inhibition of.NHMO oxidation kinetics curves of three kinds of organic matter were not consistent with the false the first-order kinetics, the late reaction existed since significant inhibition. Through the introduction of the two kinetic parameters of Sr and K, respectively, manganese dioxide oxidation of organic active sites and the reaction rate constant value based on nHMO is established. The kinetic model of SMZ oxidation can be well fitted to the whole oxidation process. With the increase of SMZ initial concentration, Sr value increases and K value decreases. With the increase of nHMO concentration, Sr value increases, K value increases, and Sr value and K value decrease with pH value increasing.
In order to study the phenomenon of dehalogenation of nHMO oxidation of halogenated phenolic compounds in the process, this paper selects three kinds of brominated phenols were investigated for the ability of oxidation of.NHMO three bromophenol were 4- bromophenol (4-BrP) 2- (2-BrP) 3- bromophenol bromophenol (3-BrP), bromine removal ability during oxidation follow the same order. Pseudo first order conditions, nHMO 4-BrP oxidation reaction rate constant with the increase of bromine phenol concentration remained unchanged, indicating that electron transfer surface complexes is the oxidation process in the speed control of debromination step.NHMO index in the process of oxidation of bromophenol (DN) with the increase of pH decreased gradually. Show that the mechanism of nHMO oxidation of bromophenol not only follow the coupling of organic free radicals. The inhibition of release were oxidized and bromide ion nitrogen aeration on the process of bromophenol, inhibitory effect and pH5.0 is more obvious than pH4.0.NHMO oxidation of bromophenol in nHMO particle size The larger the initial concentration of Bromphenol and nHMO, the lower the pH. The larger the particle size is, the more the manganese ions are adsorbed on the surface of manganese dioxide. The concentration of manganese ion in solution is very low.
In view of the oxidation activity of nHMO nanoparticles and its size, this paper also studies the phenomenon of condensation in the oxidation of nHMO. The manganese ion induced nHMO condensation with critical concentration is low, at the 10-5M level. With the increase of pH value, concentration of manganese ion by the same condensation rate increases, and the critical concentration of diffusion aggregation decreased.NHMO oxidation of organic matter in the process of condensation rate mainly depends on the reaction rate of organic compounds and caused the increase of pH value, the rate of oxidation reduction, oxidation condensation rate slowed down the condensation of.NHMO has great influence on the oxidation efficiency, adding a small amount of Potassium Permanganate.NHMO/ Potassium Permanganate combination system can unite the small oxidation initial concentration of effective control of nHMO oxidation in the process of bisphenol A M 2.5~16.8 (BPA), self inhibition phenomenon disappeared, the pseudo first-order rate constants are consistent with the rate constants of nHMO alone when the initial stage of oxidation, table Potassium Permanganate in the system mainly from the oxidation of manganese ion and maintain nHMO nanoparticles; and in the oxidation of 4- nitrophenol (4-NP), Potassium Permanganate is mainly involved in the electron transfer process of surface complexes, thereby strengthening the 4-NP removal, the combined system mainly for manganese dioxide catalytic oxidation of 4-NP. Potassium Permanganate
In addition to Potassium Permanganate manganese dioxide catalytic oxidation of pollution is very important, this paper selects the double pollutant C Masi Bing (CMZ) and phenol bisphenol A (BPA), phenol (Phen), 2- (2-CP), 2,4- two chlorophenols, chlorophenols (2,4-DCP) 2,4,6- three chloro phenol (2,4,6-TCP) as the object, study the important role of nHMO compound pollution of Potassium Permanganate oxidation formed with two kinds of organic matter and other intermediate state manganese species. Under acidic condition, CMZ can promote the oxidation of Phen and its removal is not affected; the oxidation of phenols removal performance and promote each other, and the slow oxidation of phenol removal by to promote greater catalytic effect of nHMO is the leading cause of these phenomena. In alkaline conditions, CMZ and Phen composite oxide, two removal is not influenced; between phenols compound, manifested with permanganate The oxidation reaction rate constant K low phenol removal was inhibited, while the oxidation rate constant of phenol removal by the impact is very small. The competitive kinetics shows that this inhibition is mainly two kinds of phenols in the competition system in addition to Potassium Permanganate and other nHMO species caused by oxidation activity due to oxidation. The mechanism of CMZ and Phen, two are not competitive, so the coexistence of two of their oxidation are not affected.

【學位授予單位】：哈爾濱工業(yè)大學
【學位級別】：博士
【學位授予年份】：2013
【分類號】：TU991.2

【參考文獻】

相關期刊論文 前6條

1 陳濤;李彥文;莫測輝;高鵬;吳小蓮;屈相龍;;廣州污水廠磺胺和喹諾酮抗生素污染特征研究[J];環(huán)境科學與技術;2010年06期

2 徐維海;張干;鄒世春;李向東;李平;胡朝暉;李軍;;典型抗生素類藥物在城市污水處理廠中的含量水平及其行為特征[J];環(huán)境科學;2007年08期

3 趙玲;彭平安;;二氧化錳氧化降解五氯酚的動力學模擬研究[J];環(huán)境科學;2008年04期

4 陳永山;章海波;駱永明;胡冠九;趙永剛;宋靜;;典型規(guī)�；B(yǎng)豬場廢水中獸用抗生素污染特征與去除效率研究[J];環(huán)境科學學報;2010年11期

5 常紅;胡建英;王樂征;邵兵;;城市污水處理廠中磺胺類抗生素的調查研究[J];科學通報;2008年02期

6 石為民;劉凱英;葉文婷;薛罡;程起躍;鈄晨;;磺胺甲VA唑在給水處理系統中的遷移轉化及去除研究[J];水處理技術;2011年06期

本文編號：1406805