李青松,金偉偉,馬曉雁,李國(guó)新,陳國(guó)元,高乃云,廖文超(.廈門理工學(xué)院水資源環(huán)境研究所,福建廈門 604;.浙江工業(yè)大學(xué)建筑工程學(xué)院,浙江 杭州 004;.同濟(jì)大學(xué)污染控制與資源化研究國(guó)家重點(diǎn)實(shí)驗(yàn)室,上海 0009)
高鐵酸鉀氧化去除水中三氯生的研究
李青松1*,金偉偉1,2,馬曉雁2,李國(guó)新1,陳國(guó)元1,高乃云3,廖文超1(1.廈門理工學(xué)院水資源環(huán)境研究所,福建廈門 361024;2.浙江工業(yè)大學(xué)建筑工程學(xué)院,浙江 杭州 310014;3.同濟(jì)大學(xué)污染控制與資源化研究國(guó)家重點(diǎn)實(shí)驗(yàn)室,上海 200092)
采用高鐵酸鉀對(duì)水中三氯生(TCS)的去除進(jìn)行了研究, 探討了TCS的降解機(jī)理,考察了高鐵酸鉀投加量、pH值、天然有機(jī)物(NOM)和雙氧水等因素對(duì)TCS去除和中間產(chǎn)物2,4-二氯苯酚(2,4-DCP)生成的影響.結(jié)果表明:TCS通過(guò)醚鍵斷裂降解生成2,4-DCP,TCS濃度為550μg/L,高鐵酸鉀濃度為15mg/L時(shí),600s后TCS去除率可達(dá)96.48%.增加高鐵酸鉀投加量可以提高TCS的去除,TCS的去除率隨pH值升高呈現(xiàn)出降低的趨勢(shì),酸性環(huán)境有利于TCS的去除,pH值為4時(shí),TCS的去除達(dá)100%,腐殖酸和雙氧水對(duì)TCS的去除有抑制作用.高鐵酸鉀可以有效降解TCS并降低溶液的急毒性,降低水質(zhì)健康風(fēng)險(xiǎn).
三氯生;高鐵酸鉀;2,4-二氯苯酚;降解產(chǎn)物
三氯生(2,4,4’ -三氯- 2’-羥基二苯醚,TCS)是PPCPs中一種典型的廣譜抗菌消毒劑,廣泛被添加在個(gè)人護(hù)理用品中,其濃度范圍為 0.1%~1%[1].2002年全球 TCS產(chǎn)量已達(dá)到 1500t,大約96%的TCS通過(guò)排水系統(tǒng)進(jìn)入到廢水/污水處理廠[2-3].現(xiàn)有污水處理工藝無(wú)法有效去除 TCS[4-5],導(dǎo)致其在水環(huán)境中頻被檢出[6-7].
近期研究表明TCS對(duì)水生生物具有毒害作用,并且太陽(yáng)光作用下可以形成氯仿、二惡英等毒性更大的副產(chǎn)物[8-9].這些副產(chǎn)物的積累會(huì)造成更大的環(huán)境危害.因此美國(guó)和歐盟要求對(duì) TCS的安全性展開評(píng)估[10-11].由于TCS的廣泛使用和其潛在的環(huán)境風(fēng)險(xiǎn),因此有必要展開水體中 TCS去除研究,為飲用水安全提供技術(shù)支持.
芬頓、超聲和臭氧等工藝被用來(lái)去除TCS[1,12-14].作為一種新型高效的非氯型水處理藥劑,高鐵酸鉀在整個(gè)pH值范圍均顯示出很強(qiáng)的氧化能力,高鐵酸鉀在水處理過(guò)程中兼具氧化、吸附和絮凝等多種功能[15-18],同時(shí)自身分解的產(chǎn)物為無(wú)毒的三價(jià)鐵.Yang等[19-20]考察了高鐵酸鉀氧化降解水中三氯生(TCS)的反應(yīng)動(dòng)力學(xué)和反應(yīng)機(jī)制,但有關(guān)高鐵酸鉀去除TCS時(shí)有關(guān)水質(zhì)影響對(duì)TCS去除和中間產(chǎn)物生成的影響尚未見報(bào)道.
本文采用高鐵酸鉀去除水中 TCS,考察了高鐵酸鉀去除TCS的性能,探討高鐵酸鉀投加量、pH值、腐殖酸和雙氧水等因素對(duì)TCS去除和中間產(chǎn)物2,4-DCP生成影響.以期為高鐵酸鉀深度處理污水處理廠出水和飲用水提供理論依據(jù).
1.1 試劑與儀器
TCS(德國(guó)Dr.Ehrenstorfer公司,純度>99.5%);乙腈(HPLC級(jí),德國(guó)Merck);腐殖酸(上海巨楓化學(xué)科技有限公司),質(zhì)量分?jǐn)?shù)為90% K2FeO4(天津威一化工科技有限公司)為化學(xué)純,HCl、NaOH、Na2S2O3和H2O2(30%,國(guó)藥集團(tuán)化學(xué)試劑有限公司)為分析純; BioFix? Lumi Multi-Shot 凍干細(xì)菌及激活溶液,HC-18 固相萃取柱(CNWBOND,中國(guó)),實(shí)驗(yàn)用水采用Milli-Q超純水(18.2M?).
HJ-6A數(shù)顯恒溫多頭磁力攪拌器(金壇市友聯(lián)儀器研究所),BioFix??Limi-10生物毒性分析儀(Macherey-Nagel,德國(guó)),LC-20A高效液相色譜儀(Shimadzu,日本),自動(dòng)進(jìn)樣器(SIL-20A),檢測(cè)器(SPD-M20A);UV2550 (Shimadzu,日本);GCMS-QP2010ultra (Shimadzu,日本),GC/MS自動(dòng)進(jìn)樣器(AOC-5000,日本島津),色譜柱5ms:30m×0.32mm×0.25μm,日本島津). pH 儀(Eutevch,美國(guó)).
1.2 實(shí)驗(yàn)方法
稱取 9.0mgTCS,溶于堿性溶液后配制成9mg/L的標(biāo)準(zhǔn)儲(chǔ)備液,然后再回滴至中性,使用時(shí)稀釋至所需的濃度.
1L燒杯中加入一定濃度的 TCS溶液,然后加入一定量的高鐵酸鉀,在六聯(lián)恒溫磁力攪拌器上于一定溫度下攪拌并開始計(jì)時(shí)取樣,水樣滴加過(guò)量的Na2S2O3溶液抑制反應(yīng),經(jīng)0.45μm玻璃纖維膜過(guò)濾后進(jìn)行水質(zhì)分析.
1.3 分析方法
TCS和 2,4-DCP采用 HPLC分析,采用GC/MS對(duì)TCS及其降解產(chǎn)物進(jìn)行鑒定.HPLC條件:色譜柱為 Insertsil C18 (4.6×250mm,5μm),流動(dòng)相為乙腈/水-70/30(V:V),流速為0.8mL/min,采用PDA檢測(cè)器(SPD- M20A),檢測(cè)波長(zhǎng)λ=230nm,進(jìn)樣體積10μL,S/N大于3.
GC/MS條件:載氣為高純氦氣,90kPa;進(jìn)樣量1μL;無(wú)分流進(jìn)樣方式;進(jìn)樣口溫度為 280℃;爐溫控制:初始溫度為75℃,保留1min,以10℃/min升溫至150℃,持續(xù)5min,然后以15℃/min升溫至280℃,持續(xù) 3min;MS離子化溫度為250℃;接口溫度280℃;采用scan掃描,質(zhì)量范圍:50~600m/z.
采用生物毒性儀BioTox-B測(cè)試方案進(jìn)行急毒性分析,培養(yǎng)時(shí)間為 30min,急毒性分析結(jié)果的表達(dá)形式是以抑制百分比和增強(qiáng)百分比來(lái)表示樣品里的光強(qiáng)度和沒(méi)有受到抑制的試劑空白值比較結(jié)果.
2.1 高鐵酸鉀降解TCS產(chǎn)物識(shí)別及機(jī)制
TCS初始濃度為 500μg/L,投加高鐵酸鉀10mg/L反應(yīng)10min后加入硫代硫酸鈉溶液終止反應(yīng),取500mL反應(yīng)溶液經(jīng)SPE富集、洗脫、吹干、定容后進(jìn)行GC/MS分析,結(jié)果見圖1.
由圖1可見,質(zhì)譜圖上在10.905與33.900min有兩個(gè)相對(duì)明顯的出峰.其中 33.900min時(shí)的出峰經(jīng)鑒定為TCS, 10.905min時(shí)的出峰為TCS的降解產(chǎn)物,該產(chǎn)物特征碎片為m/z 63,98,126,162,經(jīng)譜圖檢索為2,4-DCP.
圖1 高鐵酸鉀降解TCS氧化產(chǎn)物的質(zhì)譜 掃描Fig.1 MS spectra for main oxidized product of TCS bypotassium ferrate
Song等[1]和Hyun-Seok等[21]采用類芬頓和TiO2光催化去除TCS時(shí)均鑒定出了2,4-DCP[1,21].實(shí)驗(yàn)中沒(méi)有發(fā)現(xiàn)二等其他副產(chǎn)物.研究表明TCS和 2,4-DCP的 EC50分別為 0.28mg/L和4.9mg/L[22-23],因此高鐵酸鉀可以降低 TCS的毒性.
反應(yīng)中測(cè)定到了2,4-DCP的生成,高鐵酸鉀降解TCS可能是TCS分子結(jié)構(gòu)中的醚鍵的受到攻擊斷裂,進(jìn)而形成中間產(chǎn)物2,4- DCP.等物質(zhì)量的TCS可降解為等量的2,4- DCP(圖2).
圖2 高鐵酸鉀降解TCS示意Fig.2 Proposed reaction schemes for oxidation of TCS by potassium ferrate
2.2 高鐵酸鉀對(duì)TCS的去除性能
高鐵酸鉀投加量為5mg/L,TCS初始濃度為400 μg/L時(shí)降解過(guò)程中 TCS和主要降解產(chǎn)物2,4-DCP及溶液急毒性的變化見圖3.
由圖3可知,高鐵酸鉀氧化120s后TCS的去除率為63.76,600s時(shí)TCS的去除增加為75.47%.反應(yīng)過(guò)程中有2,4-DCP生成,其濃度由0s時(shí)的0μg/L增加至240s時(shí)的138 μg/L,整個(gè)反應(yīng)時(shí)間2,4-DCP一直存在.毒性測(cè)試表明反應(yīng)液的急毒性由 21%的抑制率降低至 0~3%,按照美國(guó)Microtox急毒性等級(jí)劃分方法[24],此時(shí)溶液等級(jí)為無(wú)毒或微毒.
圖3 高鐵酸鉀降解TCS過(guò)程中TCS, 2,4-DCP及溶液毒性的變化Fig.3 Evolution of acute toxicity and concentration change of TCS and 2,4-DCP during TCS degradation by potassium ferrate
TCS降解過(guò)程中忽略其他次要反應(yīng),由于等物質(zhì)量的TCS可降解為等量的2,4-DCP,因此溶液中TCS和2,4-DCP的濃度有以下的關(guān)系:
式中:C(TCS)0為TCS的初始濃度;C(2,4-DCP)和C(TCS)為反應(yīng)過(guò)程中 2,4-DCP和 TCS的濃度,μg/L;M(2,4-DCP)和M(TCS)分別為2,4-DCP和TCS的分子量,g/mol.
實(shí)驗(yàn)中不同取樣時(shí)間的TCS和2,4- DCP的濃度均能較好的符合式(1).
圖3表明了高鐵酸鉀可以有效降解TCS生成2,4-DCP,并降低溶液的急毒性.
2.3 高鐵酸鉀降解TCS影響因素
2.3.1 高鐵酸鉀投加量對(duì) TCS去除及 2,4-DCP生成影響 TCS初始濃度為 550μg/L時(shí),改變高鐵酸鉀的投加量分別為 3、5、8、10、13和16mg/L,考察高鐵酸鉀對(duì)TCS去除的影響,結(jié)果見圖4.
圖4 高鐵酸鉀投加量對(duì)TCS去除和2,4-DCP生成的影響Fig.4 Time-evolution of TCS (a) and 2,4-DCP (b) at different potassium ferrate dosage
由圖 4(a)可知,高鐵酸鉀不同投加量時(shí)均能有效去除TCS.高鐵酸鉀的投加量分別為3、5、8、10、13和16mg/L時(shí),600s內(nèi)TCS的去除率分別為 53.26、76.83、84.74、90.37、95.25和96.48%.TCS去除主要集中在前180s,高鐵酸鉀投加量為13和16mg/L時(shí),反應(yīng)180s后TCS的去除率均在90%以上.
實(shí)驗(yàn)濃度范圍內(nèi)TCS的去除率隨高鐵酸鉀濃度升高呈現(xiàn)增加的趨勢(shì).這是因?yàn)殡S著高鐵酸鹽投加量的增加,溶液中高鐵酸根的濃度增加,與TCS分子反應(yīng)的機(jī)率也增加,因此TCS的去除率逐漸增大,此后隨著高鐵酸鉀投加量的增加導(dǎo)致溶液呈堿性.高鐵酸鉀的氧化電位下降,均導(dǎo)致其氧化性減弱,所以較高高鐵酸鉀投加量時(shí)TCS去除率增加并不明顯.
圖4(b)反應(yīng)了中間產(chǎn)物2,4-DCP濃度隨時(shí)間的變化情況.由圖4(b)可知TCS去除的過(guò)程中伴隨著2,4-DCP的生成且其濃度隨TCS的去除而增加.2,4-DCP的生成主要集中在前180s,高鐵酸鉀的投加量分別為3、5、8、10、13和16mg/L時(shí),600s時(shí) 2,4-DCP的生成量分別為 115.97、176.07、268.93、283.04、272.96和 266.21μg/,此時(shí) 2,4-DCP/ TCS的生成摩爾比分別為36.01%、57.12%、85.20%、93.30%、84.68%和87.72%.
作者的前期實(shí)驗(yàn)表明高鐵酸鉀可以單獨(dú)去除2,4-DCP,但實(shí)驗(yàn)中生成的2,4-DCP并沒(méi)有和TCS同步除去.這可能因?yàn)橄鄬?duì)于醚鍵斷裂反應(yīng),TCS分子結(jié)構(gòu)中苯環(huán)開環(huán)反應(yīng)不易發(fā)生,去除反應(yīng)以醚鍵斷裂為主[25].反應(yīng)剩余高鐵酸鉀的量不足以繼續(xù)氧化去除TCS降解生成的2,4-DCP.
2.3.2 pH值對(duì) TCS去除及 2,4-DCP生成影響 高鐵酸鉀的氧化能力、穩(wěn)定性都取決于溶液的pH值大小,TCS的形態(tài)也與pH值有關(guān),因此考察了溶液pH值對(duì)TCS降解的影響.
高鐵酸鉀投加量為 10mg/L時(shí),改變?nèi)芤旱膒H值,考察pH值對(duì)TCS去除的影響,結(jié)果見圖5.由圖5可知,pH值對(duì)TCS的去除和2,4-DCP的生成有著顯著的影響.
實(shí)驗(yàn)范圍內(nèi)TCS去除率隨pH值升高而降低.pH值為 9時(shí),600s時(shí) TCS去除率僅為11.83%.pH值為8、7、6及5時(shí),TCS去除率分別增加為 32.32%、77.65%、80.91%和 91.38%.當(dāng) pH值為 4時(shí),TCS的去除率最高,此時(shí)不僅TCS的濃度已低于檢測(cè)限,而且生成的2,4-DCP也得到了部分去除,濃度由180s時(shí)246.72μg/L降低為600s的213.97μg/L.圖5表明pH值顯著影響TCS的去除,TCS去除率隨pH值升高而升高.
圖5 pH值TCS去除和2,4-DCP生成的影響Fig.5 Time-evolution of TCS (a) and 2,4-DCP (b) at different pHs
較高的pH值不利于TCS的去除,進(jìn)而降低2,4-DCP的生成.pH值為8和9時(shí)2,4-DCP的生成量為94.27和19.10μg/L,顯著低于其他pH值時(shí)200μg/L左右的生成量.
首先,pH值影響高鐵酸鹽的氧化還原電位和溶液的穩(wěn)定性.酸性條件下高鐵酸鉀的氧化電位可達(dá) 2.20V,但穩(wěn)定性較差;偏堿性溶液雖然可以增加高鐵酸鉀的穩(wěn)定性,保證其與反應(yīng)物有更長(zhǎng)的反應(yīng)時(shí)間,但堿性條件下氧化電位高鐵酸鉀的氧化還原電位較低,僅為0.72V[26-28].
其次,pH值能改變TCS的存在形態(tài)和親疏水性,影響到其在反應(yīng)溶液中的分布和去除途徑.TCS為疏水性、弱揮發(fā)性物質(zhì),當(dāng)溶液是弱堿時(shí),TCS一部分以分子形式存在(TCS的 pKa= 7.9)[29],強(qiáng)堿環(huán)境中TCS是以負(fù)離子形式存在.堿性條件下高鐵酸根主要以 FeO42-為存在形態(tài),在堿性條件下均帶負(fù)電荷的FeO42-和TCS分子的兩種離子之間,存在靜電相斥作用,二者之間有效碰撞幾率小,這影響了FeO42-對(duì)TCS的氧化降解作用,而在酸性條件下,TCS大部分以中性分子的形態(tài)存在,與堿性環(huán)境相比,F(xiàn)eO42-與TCS之間有效碰撞幾率增大,有利于高鐵酸鹽對(duì)TCS的氧化降解.
圖5(a)表明實(shí)驗(yàn)范圍內(nèi)TCS的去除率隨pH值增加而逐漸降低,這與楊濱等[30]考察高鐵酸鉀氧化降解TCS動(dòng)力學(xué)研究時(shí)反應(yīng)速率常數(shù)隨pH值的增加逐漸降低的結(jié)論類似,但與高鐵酸鉀降解鄰氯苯酚的趨勢(shì)并不一致[31].
TCS的去除率隨pH值增加而逐漸降低是高鐵酸根氧化還原電位、穩(wěn)定性及TCS電離電位等3種影響因素共同作用的結(jié)果,實(shí)驗(yàn)結(jié)果表明高鐵酸根氧化還原電位在TCS的降解中起主導(dǎo)作用.
2.3.3 天然有機(jī)物對(duì)TCS去除及2,4-DCP生成影響 自然水體中常含天然有機(jī)物(NOM),實(shí)驗(yàn)中以腐殖酸(HA)模擬NOM,調(diào)整溶液中腐殖酸含量值,在TCS的濃度為550μg/L,高鐵酸鉀投加量為10mg/L時(shí),考察有機(jī)物對(duì)TCS去除的影響,結(jié)果見圖6.
圖6 NOM對(duì)TCS去除和2,4-DCP生成的影響Fig.6 Time-evolution of TCS (a) and 2,4-DCP (b) at different NOM concentrations
由圖6可知,實(shí)驗(yàn)范圍內(nèi)TCS去除隨NOM含量的升高而降低,2,4-DCP的生成量隨 NOM含量的增加而降低.NOM含量為 0時(shí),600s時(shí)TCS去除率為92.58%,NOM含量為0.015、0.038、0.107、0.0128及0.159UV254-1時(shí),TCS去除率分別降低為78.20%、57.27%、38.12%、30.65%和28.65%.由TCS降解產(chǎn)生的2,4-DCP也隨之呈生成減少的趨勢(shì).當(dāng) NOM 含量為 0.0128和0.159UV254
-1時(shí),由于TCS去除率太低,實(shí)驗(yàn)中沒(méi)有測(cè)出2,4-DCP的生成.
NOM的存在可以降低TCS的去除率,這是因?yàn)楦乘岷兄T如羧基、酚羥基、醇羥基等基團(tuán),高鐵酸鉀可以直接或通過(guò)高鐵酸鉀自分解產(chǎn)生的氧化物質(zhì)氧化除去腐殖酸[32],因此腐殖酸可以與反應(yīng)體系中的TCS競(jìng)爭(zhēng)高鐵酸鉀,從而對(duì)高鐵酸鉀氧化降解TCS產(chǎn)生不利影響.
2.2.4 雙氧水對(duì)TCS去除及2,4-DCP生成影響自然水體中存在一定濃度的雙氧水(H2O2)、羥基自由基(·OH)、單線態(tài)氧(1O2)等ROS,它們對(duì)水環(huán)境中物質(zhì)的化學(xué)行為有重要影響.因此實(shí)驗(yàn)中考察雙氧水對(duì)TCS去除的影響,結(jié)果見圖7.
圖7 雙氧水對(duì)TCS去除和2,4-DCP生成的影響Fig.7 Time-evolution of TCS (a) and 2,4-DCP (b) at different hydrogen peroxide concentrations
由圖7可知,TCS去除率隨雙氧水投加量的增加而下降,雙氧水投加量為0、1、3、5、7和10mg/L時(shí),TCS的去除率為90.34%、77.82%、62.46%、53.62%、49.79%和 36.43%. 600s時(shí)2,4-DCP的生成量也有 262.51μg/L [C(H2O2)= 0mg/L]降低為122.13 μg/L [C(H2O2) =10mg/L].
有研究[33-34]表明H2O2可以和高鐵酸鉀氧化過(guò)程中產(chǎn)生的Fe2+形成Fenton體系,進(jìn)一步強(qiáng)化高鐵酸鉀氧化降解有機(jī)物的能力.但在實(shí)驗(yàn)中未證實(shí)這一點(diǎn),實(shí)驗(yàn)范圍內(nèi)雙氧水均不同程度地抑制了氧化反應(yīng)的進(jìn)行.這可能是因?yàn)樽鳛橐环N強(qiáng)氧化劑,高鐵酸鉀能和雙氧水發(fā)生反應(yīng)生成氧氣:
導(dǎo)致溶液中高鐵酸鉀的消耗,從而降低了TCS的去除率.
3.1 高鐵酸鉀可以有效用于去除水中的 TCS,高鐵酸鉀投加量為15mg/L,TCS濃度為550μg/L時(shí),TCS去除率可達(dá)96.48%.
3.2 TCS通過(guò)醚鍵的斷裂降解生成中間產(chǎn)物2,4-DCP.
3.3 高鐵酸鉀氧化可以降低溶液的急毒性,TCS的去除伴隨著2,4-DCP的生成, 2,4-DCP的生成兩取決于TCS的降解, TCS的去除和溶液急毒性的降低并不是同步過(guò)程.
3.4 TCS的去除率高鐵酸鉀濃度的增加而增加,TCS去除率隨pH值升高而降低,腐殖酸和雙氧水對(duì) TCS的降解有抑制作用,二者可以降低TCS的去除率和2,4-DCP的生成.
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Study on the degradation of triclosan in aqueous by potassium ferrate.
LI Qing-song1*, JIN Wei-wei1,2, MA Xiao-yan2, LI Guo-xin1, CHEN Guo-yuan1, GAO Nai-yun3, LIAO Wen-chao1(1.Water Resources and Environmental Institute, Xiamen University of Technology, Xiamen 361005, China;2.College of Civil Engineering and Architecture,Zhejiang University of Technology, Hangzhou 310014, China;3.National Key Laboratory of Pollution Control and Reuse,Tongji University, Shanghai 200092, China). China Environmental Science, 2016,36(9):2665~2671
The degradation of triclosan (TCS) in aqueous by potassium ferrate was investigated, and the degradation mechanism of TCS was researched. Besides, the effects of different factors, such as potassium ferrate dosage, TCS initial concentration, pH, natural organic matter (NOM) and hydrogen peroxide on TCS degradation and the 2,4-DCP formation during potassium ferrate oxidation was specifically discussed. The results indicated that TCS was degraded into 2,4-DCP via cleavage of the ether bond. The degradation rate of TCS could reach 96.48% within 600s under TCS initial concentration of 550μg/L, and potassium ferrate dosage of 15mg/L. The oxidation of TCS was not a simultaneous detoxification process. The degradation of TCS was showed positive correlation with the increase of potassium ferrate dosage, but decreased with the increase of pH. Acid environment was conducive to the TCS removal, and the removal of TCS reached 100% when pH value was 10.7. However, TCS removal was inhibited by the presence of NOM and hydrogen peroxide. Potassium ferrate can effectively degrade TCS, lower acute toxicity of reaction solution, and therefore,reduce health risk of water quality.
triclosan;potassium ferrate;2,4-DCP;degradation product
X703.1
A
1000-6923(2016)09-2665-07
2016-01-06
國(guó)家自然基金項(xiàng)目(51378446,51309197,51408518);福建省高等學(xué)校新世紀(jì)優(yōu)秀人才支持計(jì)劃資助(JA14227);福建省自然科學(xué)基金 (2016J01695);廈 門市 科技局 項(xiàng) 目(3502Z20131157,3502Z20150051)
* 責(zé)任作者, 副研究員, leetsingsong@sina.com
李青松(1979-),男,山東東明人,副研究員,博士,主要從事水處理理論與技術(shù)研究.發(fā)表論文50余篇.