本文關(guān)鍵詞： 飲用水 三氯硝基甲烷 前體物 形成機(jī)理 控制技術(shù)　出處：《昆明理工大學(xué)》2012年博士論文　論文類型：學(xué)位論文

【摘要】：飲用水安全問題是人類最關(guān)注的問題之一,飲用水消毒副產(chǎn)物具有致癌作用、細(xì)胞遺傳毒性和致突變性,對人們的身體健康產(chǎn)生極大的危害,因此對飲用水消毒副產(chǎn)物的研究具有重要的現(xiàn)實(shí)意義。 本論文采用氣相色譜/質(zhì)譜法,選擇甲基叔丁基醚為萃取劑,1,2.二溴丙烷為內(nèi)標(biāo)物,建立了含氮消毒副產(chǎn)物三氯硝基甲烷(TCNM)的測定方法。以甲胺為前體物,考察了消毒副產(chǎn)物TCNM的生成過程及影響因素。以三氯硝基甲烷為研究對象,分別采用活性炭吸附、鐵還原和高級氧化技術(shù),系統(tǒng)研究了TCNM的控制技術(shù),分析了其降解機(jī)理及動力學(xué)規(guī)律。 根據(jù)加標(biāo)回收率和精密度試驗(yàn)結(jié)果,本研究建立的三氯硝基甲烷的測定方法,具有較高的準(zhǔn)確度,其回收率為97.3%.106%,相對標(biāo)準(zhǔn)偏差為1.43%-2.25%,最小檢測限(MDL)小于1μg/L。 以甲胺為前體物,考察了消毒副產(chǎn)物TCNM的生成過程、影響因素。結(jié)果表明：pH在堿性條件下TCNM的生成量比中性和酸性條件下高,TCNM的生成量隨著pH的增大而逐漸提高。在投氯量2-8mmol/L的范圍內(nèi),TCNM的生成量隨著投氯量的增加而提高,當(dāng)投氯量由8mmol/L增加到12mmol/L時,因自由氯的濃度較高,甲胺還通過其它路徑發(fā)生反應(yīng)生成了腈類和醛類,從而使TCNM的生成量降低。在10.30℃范圍內(nèi),溫度對甲胺生成TCNM的影響較明顯,溫度越高,TCNM的生成量越高。甲胺氯化形成TCNM的過程符合親電反應(yīng)的機(jī)理,HCl0和C10-可以作為親電試劑進(jìn)攻甲胺最終形成TCNM。 為了提高活性炭對TCNM的去除效率,采用NaOH (30%, w/v)對顆粒活性炭進(jìn)行改性,以提高其吸附容量。分別采用比表面孔徑分布測定儀、掃描電鏡、傅立葉紅外變換光譜等先進(jìn)儀器及Boehm官能團(tuán)滴定法,對改性前后活性炭的表面理化性質(zhì)進(jìn)行表征。結(jié)果表明：NaOH-GAC的比表面積比GAC增加了9.47%,NaOH-GAC的表面的酸性基團(tuán)(羧基、內(nèi)酯基、酚羥基)比GAC減少了29.6%,改性活性炭對三氯硝基甲烷的吸附容量大大增加。 吸附試驗(yàn)結(jié)果表明：對于濃度為10μg/L的三氯硝基甲烷溶液,吸附劑投加量為0.3g/L時,NaOH-GAC的吸附去除率為87%,是GAC的1.71倍。吸附劑對三氯硝基甲烷的吸附過程大致分3個階段：快速階段、慢速階段和動態(tài)平衡階段。GAC吸附三氯硝基甲烷溶液的吸附平衡時間為36h,30%NaOH-GAC吸附三氯硝基甲烷溶液的吸附平衡時間為6h。 鐵刨花對低濃度的三氯硝基甲烷有較好的去除效果,對于100ml濃度為5μtg/L的三氯硝基甲烷溶液,當(dāng)鐵刨花的投加量為4g時,反應(yīng)180min后,去除率達(dá)到90.15%。鐵刨花投加量對三氯硝基甲烷的去除效果影響較大,隨著鐵刨花投加量的增加,三氯硝基甲烷的去除率增加。在低濃度三氯硝基甲烷濃度條件下,三氯硝基甲烷初始濃度的變化對去除三氯硝基甲烷的去除效果影響不大。鐵刨花還原去除三氯硝基甲烷的反應(yīng)符合一級反應(yīng)動力學(xué)規(guī)律。 當(dāng)三氯硝基甲烷初始濃度為20μg/L時,反應(yīng)150min后,單獨(dú)H202降解時,隨著反應(yīng)時間和H2O2投加量的增加,三氯硝基甲烷去除率逐漸提高,H2O2投加量為15mg/L,去除率達(dá)到39.54%；單獨(dú)03降解三氯硝基甲烷,隨著臭氧的投加濃度增加,三氯硝基甲烷去除率提高,臭氧濃度控制為10.06mg/L,去除率為35.30%；單獨(dú)UV降解,隨著紫外光強(qiáng)的增加,紫外光對三氯硝基甲烷的去除率明顯提高,紫外光強(qiáng)為31μw/cm2時,去除率為43.53%。 聯(lián)合工藝對三氯硝基甲烷有更好的去除效果。在UV-H2O2工藝中,控制紫外光強(qiáng)為31μw/cm2,當(dāng)H202投加量在15-45mg/L范圍內(nèi)時,隨著H202投加量的增加,三氯硝基甲烷去除率有較為明顯的提高。當(dāng)H202投加量從15mg/L增加到45mg/L時,初始濃度為20μg/L的三氯硝基甲烷在反應(yīng)150min后,去除率從82.26%提高到95.61%。而且隨著紫外光強(qiáng)的增加,UV-H2O2聯(lián)合工藝對三氯硝基甲烷的去除率,也有較為明顯的提高。在UV-H2O2-O3聯(lián)合工藝中,在紫外光強(qiáng)為31μw/cm2,H202投加量為15mg/L,臭氧投加量為10.06mg/L的條件下,初始濃度為20μg/L的三氯硝基甲烷在反應(yīng)150min后,去除率達(dá)到了97.28%的最高值。UV-H2O2-O3聯(lián)合工藝降解三氯硝基甲烷符合一級反應(yīng)動力學(xué)。
[Abstract]:The safety of drinking water is one of the most important problems of human being . The disinfection by - products of drinking water has the carcinogenic effect , the cytogenetics toxicity and the mutagenicity . It has great harm to the health of people . Therefore , the research on disinfection by - products of drinking water has important practical significance . In this paper , a method for the determination of the production process and the influencing factors of the disinfection by - product , trichloronitromethane , was established by using gas chromatography / mass spectrometry ( GC / MS ) as the extractant , 1,2 . dibromopropane as internal standard . According to the results of recovery and precision test , the method for determination of trichloronitromethane has high accuracy , the recovery rate is 97.3 % . 106 % , the relative standard deviation is 1 . 43 % - 2.25 % , and the minimum detection limit ( mdl ) is less than 1 渭g / L . In the range of 2 - 8 mmol / L , the amount of the product is increased with the increase of the pH value . In order to improve the removal efficiency of activated carbon , the granular activated carbon was modified by NaOH ( 30 % , w / v ) to improve its adsorption capacity . The experimental results show that the adsorption removal rate of NaOH - GAC is 87 % for trichloronitromethane solution with concentration of 10渭g / L . The adsorption removal rate of NaOH - GAC is 87 % , which is 1 . 71 times of GAC . The adsorption process of adsorbent to trichloronitromethane is divided into three stages : fast stage , slow phase and dynamic equilibrium stage . The adsorption equilibrium time of GAC adsorption of trichloronitromethane solution is 36 h , and the adsorption equilibrium time of 30 % NaOH - GAC adsorption trichloronitromethane solution is 6h . The removal efficiency of 3 - chloronitromethane was 90 . 15 % . The removal rate of trichloronitromethane increased with the increase of the amount of iron shavings added . The removal of trichloronitromethane was not affected by the change of the initial concentration of trichloronitromethane . When the initial concentration of trichloronitromethane was 20 渭g / L , the removal rate of trichloronitromethane increased with the increase of reaction time and H2O2 dosage , the removal rate was 39.54 % , the removal rate was 39.54 % , the removal rate was 39.54 % , the removal rate was 10.06 mg / L , the removal rate was 35.30 % , the removal rate was 10.06 mg / L , the removal rate was 10.06 mg / L , and the removal rate was 31.mu w / cm2 , and the removal rate was 43.53 % . In the UV - H _ 2O _ 2 - O3 combined process , the removal rate of trichloronitromethane was increased from 82.26 % to 95.61 % .

【學(xué)位授予單位】：昆明理工大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2012
【分類號】：X131;R123.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 顧春暉,鄭正,楊光俊,宋衛(wèi)華,杭德生;輻照降解飲用水氯化消毒副產(chǎn)物的研究[J];環(huán)境科學(xué)與技術(shù);2005年02期

2 周紅藝,汪大，

本文編號：1446691