液相射頻放電等離子體降解水中三氯甲烷和腐殖酸的研究
發(fā)布時間：2018-10-14 18:30
【摘要】：三氯甲烷(CHCl3)屬于常見的鹵代有機污染物,廣泛應(yīng)用于工業(yè)生產(chǎn)生活中,也可由氯法消毒產(chǎn)生,長期接觸對人體健康有嚴(yán)重危害。腐殖酸(HA)廣泛存在于天然水體中,是氯法消毒生成三氯甲烷反應(yīng)的前驅(qū)物質(zhì),同時也可增加患大骨節(jié)病的概率、引起水體渾濁等環(huán)境問題。近年來,液相射頻等離子體因為具有擊穿電壓低,可在常壓發(fā)生,能量效率高等特點而逐漸得到了越來越多的關(guān)注。本研究自行設(shè)計了液相射頻等離子體發(fā)生裝置,研究了其對三氯甲烷和腐殖酸的降解效果,主要結(jié)論如下:(1)通過發(fā)射光譜檢測到液相射頻等離子體中主要產(chǎn)生的自由基為.OH和·H,電導(dǎo)率范圍在0.10～0.80mS/cm時,·OH的發(fā)射強度隨著電導(dǎo)率的增大而增強;電導(dǎo)率范圍在0.80～6.00mS/cm時,.OH的發(fā)射強度隨著電導(dǎo)率的增大而減弱;(2)提高溶液初始pH、添加自由基清除劑、NO3-可以提高CHCl3的去除率,HCO3-可以起到緩沖作用和消耗·OH間接提高·H濃度的作用,產(chǎn)物無污染,是提高CHC13去除率的理想物質(zhì);主要降解中間產(chǎn)物為HCOOH、H2C2O4和CH2Cl2,·H和eaq-是引發(fā)CHCl3脫氯的關(guān)鍵物質(zhì),并對有機酸和二氯甲基自由基的產(chǎn)生和轉(zhuǎn)化起到重要作用,·OH則主要對有機酸的降解做出貢獻(xiàn),最終產(chǎn)物為CO2、H2O和HCl,放電過程中的局部高溫對CHCl3的富集和熱解也有助于其去除;液相射頻等離子體技術(shù)也可對CH2Cl2進(jìn)行有效去除,機理與CHCl3類似;(3)加入Fe2+與溶液中產(chǎn)生的H202形成Fenton反應(yīng)協(xié)同處理HA取得了很好的效果,最佳pH范圍為3.50～5.50,當(dāng)HA初始濃度30mg/L時,最佳Fe2+投加濃度為20mg/L,去除率可達(dá)90.23%;對于高濃度的HA溶液也有良好的去除效果,Fe2+初始濃度20mg/L,HA初始濃度60mg/L時,HA去除率可達(dá)95.33%;經(jīng)放電處理后HA的芳香度減弱,大分子被分解為小分子,C=C、C-O、羥基強度下降,而-CH-的強度有所增加。
[Abstract]:Trichloromethane (CHCl3), a common halogenated organic pollutant, is widely used in industrial production and can also be produced by chlorine disinfection. Humic acid (HA) is a precursor of chlorination to form trichloromethane in natural water, and it can also increase the probability of Kaschin-Beck disease and cause environmental problems such as turbidity of water body. In recent years, more and more attention has been paid to liquid radio frequency plasma because of its low breakdown voltage, high energy efficiency and low breakdown voltage. In this study, a liquid phase RF plasma generator was designed to study the degradation of trichloromethane and humic acid. The main conclusions are as follows: (1) the main free radicals produced in liquid radio frequency plasma are. OH and H by emission spectrum. When the conductivity range is 0.10~0.80mS/cm, the emission intensity of OH increases with the increase of conductivity. When the conductivity is in the range of 0.80~6.00mS/cm, the emission intensity of,. OH decreases with the increase of conductivity. (2) when the solution initial pH, is added with free radical scavenger, NO3- can increase the removal rate of CHCl3, HCO3- can play a buffer role and consume OH to increase H concentration indirectly. The main degradation intermediates are HCOOH,H2C2O4, CH2Cl2, H and eaq-, which are the key substances to initiate the dechlorination of CHCl3. It also plays an important role in the production and transformation of organic acids and dichloromethyl radicals, while OH mainly contributes to the degradation of organic acids. The final product is the partial high temperature during the discharge of CO2,H2O and HCl, and the enrichment and pyrolysis of CHCl3 are also helpful to its removal. The liquid-phase RF plasma technology can also effectively remove CH2Cl2, and the mechanism is similar to that of CHCl3. (3) the synergistic treatment of HA with H202 produced in solution by adding Fe2 has a good effect. The optimum pH range is 3.50 ~ 5.50, and when the initial concentration of HA is 30mg/L, The optimal concentration of Fe2 was 20mg / L, and the removal rate was 90.23.The removal rate of HA was 95.33 when the initial concentration of Fe2 was 20mg / L, 60mg/L, and the aromaticity of HA decreased after the discharge treatment. When the macromolecules are decomposed into small molecules, the strength of the hydroxyl group decreases, while the strength of-CH- increases.
【學(xué)位授予單位】：大連海事大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：X703
本文編號：2271272
[Abstract]:Trichloromethane (CHCl3), a common halogenated organic pollutant, is widely used in industrial production and can also be produced by chlorine disinfection. Humic acid (HA) is a precursor of chlorination to form trichloromethane in natural water, and it can also increase the probability of Kaschin-Beck disease and cause environmental problems such as turbidity of water body. In recent years, more and more attention has been paid to liquid radio frequency plasma because of its low breakdown voltage, high energy efficiency and low breakdown voltage. In this study, a liquid phase RF plasma generator was designed to study the degradation of trichloromethane and humic acid. The main conclusions are as follows: (1) the main free radicals produced in liquid radio frequency plasma are. OH and H by emission spectrum. When the conductivity range is 0.10~0.80mS/cm, the emission intensity of OH increases with the increase of conductivity. When the conductivity is in the range of 0.80~6.00mS/cm, the emission intensity of,. OH decreases with the increase of conductivity. (2) when the solution initial pH, is added with free radical scavenger, NO3- can increase the removal rate of CHCl3, HCO3- can play a buffer role and consume OH to increase H concentration indirectly. The main degradation intermediates are HCOOH,H2C2O4, CH2Cl2, H and eaq-, which are the key substances to initiate the dechlorination of CHCl3. It also plays an important role in the production and transformation of organic acids and dichloromethyl radicals, while OH mainly contributes to the degradation of organic acids. The final product is the partial high temperature during the discharge of CO2,H2O and HCl, and the enrichment and pyrolysis of CHCl3 are also helpful to its removal. The liquid-phase RF plasma technology can also effectively remove CH2Cl2, and the mechanism is similar to that of CHCl3. (3) the synergistic treatment of HA with H202 produced in solution by adding Fe2 has a good effect. The optimum pH range is 3.50 ~ 5.50, and when the initial concentration of HA is 30mg/L, The optimal concentration of Fe2 was 20mg / L, and the removal rate was 90.23.The removal rate of HA was 95.33 when the initial concentration of Fe2 was 20mg / L, 60mg/L, and the aromaticity of HA decreased after the discharge treatment. When the macromolecules are decomposed into small molecules, the strength of the hydroxyl group decreases, while the strength of-CH- increases.
【學(xué)位授予單位】：大連海事大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：X703
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 王珂;陳小岳;;飲用水消毒副產(chǎn)物對健康的危害及其影響因素研究進(jìn)展[J];職業(yè)與健康;2015年20期
2 張波;宣鳳琴;李德明;;水中氯仿處理技術(shù)的研究現(xiàn)狀與展望[J];湖北理工學(xué)院學(xué)報;2014年03期
3 唐慧敏;;飲用水氯化消毒副產(chǎn)物的安全控制[J];低碳世界;2014年11期
4 張峰振;吳超飛;胡蕓;韋朝海;;鹵代有機污染物的光化學(xué)降解[J];化學(xué)進(jìn)展;2014年06期
5 古麗君;肖烽;;飲用水凈化處理技術(shù)的進(jìn)展[J];廣東化工;2014年07期
6 王瑾瑜;孫亞兵;繆虹;徐建華;馮景偉;;電暈放電等離子體同時去除水中Cr(Ⅵ)和苯酚的實驗研究[J];環(huán)境科學(xué)學(xué)報;2012年10期
7 吉亮亮;鄒帥;沈明榮;辛煜;;Radio Frequency Underwater Discharge Operation and Its Application to Congo Red Degradation[J];Plasma Science and Technology;2012年02期
8 塔春紅;韓相奎;荊玲;邵永武;;氯消毒副產(chǎn)物及其影響因素的研究概況[J];遼寧化工;2012年01期
9 陳燕;趙劍;;東烏煤及不同化學(xué)組分的傅里葉紅外分析[J];山西煤炭;2011年07期
10 鄭國庚;賈彥博;屠海云;;飲用水中消毒副產(chǎn)物的分析與安全性評價[J];中國食物與營養(yǎng);2011年06期
相關(guān)碩士學(xué)位論文 前1條
1 張雪梅;活性炭及粉煤灰對水中腐殖質(zhì)脫除性能的研究[D];大連理工大學(xué);2014年
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