閆 松,張成武,李天一,秦傳玉*

基于PMS的Cr(VI)-染料復(fù)合廢水協(xié)同處理效果及機理

閆 松1,2,張成武1,2,李天一1,2,秦傳玉1,2*

(1.吉林大學(xué)地下水資源與環(huán)境教育部重點實驗室,吉林 長春 130012；2.吉林大學(xué)新能源與環(huán)境學(xué)院,吉林 長春 130012)

通過投加過一硫酸鹽(PMS)探討其協(xié)同處理偶氮染料金橙II(AO7)及Cr(VI)的可行性、影響因素及機理.結(jié)果表明,體系可以在有效去除AO7的同時降低Cr(VI)濃度,120min時降解率分別達(dá)到97.9%及22.1%;隨著初始pH值降低AO7降解及Cr(VI)去除效率逐漸升高;AO7的降解主要是由于Cl-與PMS反應(yīng)產(chǎn)生的氧化性物質(zhì)HClO以及PMS投加創(chuàng)造的酸性條件使得Cr(VI)具有強氧化性的共同作用,其中起主導(dǎo)作用的是HClO;Cr(VI)的轉(zhuǎn)化是由于自身與AO7發(fā)生氧化還原反應(yīng)導(dǎo)致.本研究可以為復(fù)合污染廢水的處理提供理論依據(jù).

染料廢水；復(fù)合污染；過一硫酸鹽；Cr(VI)；協(xié)同處理

印染廢水成分復(fù)雜,不僅含有大量難降解的偶氮染料,還有以氯化鈉為主的無機鹽[1]以及滾筒剝鉻產(chǎn)生的含鉻物質(zhì),是典型的含鹽含鉻有機廢水.對于Cr(VI)或染料廢水的單獨處理技術(shù)已經(jīng)相對成熟,而對于Cr(VI)-染料復(fù)合污染的協(xié)同處理研究報道較少,相對于生物法[2-4]及物理吸附法[5-6]耗時長、處理效果差等缺點,化學(xué)法展現(xiàn)出了見效快且效果好等優(yōu)點;有學(xué)者利用零價鐵還原Cr(VI)同時零價鐵與氧氣反應(yīng)在有配體存在下生成高活性自由基降解染料,但該方法成本較高且容易生成大量鐵泥[7-8];利用光催化二氧化鈦也可以同時降解染料及Cr(VI)[9-10],但Cl-會競爭TiO2表面的活性吸附位點從而影響光催化氧化,且會改變TiO2的空間結(jié)構(gòu)使TiO2失活[11-13].因此尋找一種低成本且在Cl-存在下仍可以有效處理Cr(VI)-染料復(fù)合污染的方法具有重要意義.

近年來有文獻(xiàn)報道Cl-可以活化過一硫酸鹽(PMS)產(chǎn)生活性物質(zhì)降解污染物[14-16];同時過渡金屬離子如Fe2+、Co2+、Mn2+、Ce3+等[17-18]可以活化PMS產(chǎn)生硫酸根自由基(SO4·—),Cr(VI)作為一種過渡金屬已被報道可以活化H2O2產(chǎn)生羥基自由基(×OH)[19],而PMS與H2O2具有相似的結(jié)構(gòu)且氧化還原電位相近(分別為+1.82V(PMS)和+1.77V (H2O2))[20],因此考慮Cr(VI)是否具有活化PMS降解污染物的潛力,從而通過在含鹽含鉻染料廢水中添加PMS達(dá)到同時去除染料和Cr(VI)的目的.

本文通過添加氯化鈉、重鉻酸鉀、代表性偶氮染料AO7來模擬含鹽含鉻染料廢水,加入PMS研究該體系協(xié)同處理偶氮染料AO7及Cr(VI)的可行性、影響因素及反應(yīng)機理.

1 實驗部分

1.1 實驗試劑

過硫酸氫鉀(KHSO5×0.5KHSO4×0.5K2SO4),金橙II(上海阿拉丁生化科技股份有限公司);重鉻酸鉀(99.8%,天津市光復(fù)科技發(fā)展有限公司);氯化鈉,氫氧化鈉,硫酸,磷酸(分析純,北京化工廠);二苯碳酰二肼(分析純,國藥集團化學(xué)試劑有限公司);叔丁醇,硫酸銨(化學(xué)純,國藥集團化學(xué)試劑有限公司);乙醇(分析純,天津天泰精細(xì)化學(xué)品有限公司);甲醇(分析純,西隴科學(xué)股份有限公司).

1.2 實驗儀器

HZK-210電子天平(福州華志科學(xué)儀器有限公司), YSI pH100pH計(美國黃泉儀器有限公司), HJ- 6A數(shù)顯恒溫磁力攪拌器(金壇市醫(yī)療儀器廠), EVOLUTION 201紫外分光光度計(Thermo Fisher Scientific - Shanghai), SPECTRONIC 200E可見分光光度計(Thermo Fisher Scientific - Shanghai), Thermo TSQ三重串聯(lián)四級桿質(zhì)譜儀.

1.3 實驗方法

所有實驗通過使用250mL錐形瓶在室溫(25±2)℃下進(jìn)行;向特定濃度的AO7水溶液中依次加入一定量的重鉻酸鉀及氯化鈉,置于磁力攪拌器上攪拌,轉(zhuǎn)速控制在500r/min左右;加入所需量的PMS進(jìn)行反應(yīng),在反應(yīng)期間不控制pH值;在特定的時間間隔取出樣品并立即分析.每組實驗重復(fù)三次,最終結(jié)果取平均值.

1.4 分析方法

Cr(VI)濃度測定采用二苯碳酰二肼分光光度法[21]; AO7濃度測定采用直接分光光度法,于484nm處有特征吸收峰;AO7中間產(chǎn)物采用LC-MS測定,采取手動進(jìn)樣,洗脫液為乙腈,流速為0.2mL/min,采用負(fù)離子掃描模式在/為40~200范圍內(nèi)獲得MS光譜.應(yīng)用Excel2010、OriginPro8.0進(jìn)行數(shù)據(jù)分析處理與作圖.

2 結(jié)果及分析

2.1 不同組分體系降解AO7效果

對比不同組分體系中AO7的降解率及Cr(VI)的去除率,結(jié)果如圖1所示.PMS單獨降解AO7在120min內(nèi)效率僅為3.2%,幾乎不降解;PMS/Cr(VI)、PMS/Cl-以及PMS/Cr(VI)/Cl-體系均可以降解AO7, 120min時降解率分別達(dá)到58.8%、88.9%及97.9%;反應(yīng)結(jié)束后Cr(VI)轉(zhuǎn)化為毒性更低的Cr(III),PMS/ Cr(VI)及PMS/Cr(VI)/Cl-體系Cr(VI)去除率可分別達(dá)到35.9%及22.1%.

由上述結(jié)果可知,PMS與Cl-反應(yīng)可以有效降解AO7,Cr(VI)同時存在可以提高AO7的降解效率,且Cr(VI)自身可以達(dá)到一定程度的去除.

PMS=7.83mM, Cl-=14mM,Cr(VI)=0.38mM, AO7=0.3mM, pH0=2.5

2.2 PMS/Cl-體系降解AO7

2.2.1 Cl-濃度對體系降解的影響 分別選取濃度為5.6,14,28mmol/L 的Cl-進(jìn)行實驗,結(jié)果如圖2所示.隨著Cl-濃度增加,AO7降解效率逐漸升高,120min時AO7降解率分別達(dá)到56.5%、88.9%及99.1%;雖然28mmol/L的Cl-體系降解效率較高,但其在60min已接近反應(yīng)完全,不方便后續(xù)研究,因此選取14mmol/L作為實驗Cl-濃度進(jìn)行后續(xù)研究.

2.2.2 初始pH值對體系降解的影響 有文獻(xiàn)報道堿可以直接活化PMS產(chǎn)生活性物質(zhì)降解污染物[22],為避免堿性條件干擾體系降解AO7的實驗結(jié)果,僅探究酸性條件下初始pH值的變化對于體系降解AO7的影響,結(jié)果如圖3所示.初始pH值在4.5及6.5的條件下AO7的降解率仍能達(dá)到97.9%,因此酸性條件下PMS/Cl-體系對AO7的降解效率基本不受初始pH值的影響.

圖2 不同Cl-濃度對AO7降解的影響

PMS=7.83mmol/L, AO7=0.3mmol/L,pH0=2.5

圖3 不同初始pH值對AO7降解的影響

PMS=7.83mmol/L, Cl-=14mmol/L, AO7=0.3mmol/L

2.2.3 HClO掩蔽劑對體系降解的影響 Wang等[23]考察Cl-對Co2+/PMS體系降解AO7的研究中發(fā)現(xiàn)較高濃度的Cl-可以活化PMS生成活性氯與AO7反應(yīng),且有研究表明NH4+不能被SO4·—和×OH 氧化,但是可以與HClO發(fā)生反應(yīng)生成活性較低的NH2Cl、NHCl2和NCl3[24-26],因此選用硫酸銨作為HClO掩蔽劑進(jìn)行掩蔽實驗,結(jié)果如圖4所示.不添加掩蔽劑時體系降解效率為88.9%;添加15mmol/L硫酸銨后體系降解效率降低至43.5%;添加150mmol/L硫酸銨后體系降解效率降低至3.4%,與PMS單獨降解效率相近.因此說明該體系中AO7的降解是HClO的作用.

圖4 不同HClO掩蔽劑濃度對AO7降解的影響

PMS=7.83mmol/L, Cl-=14mmol/L, AO7=0.3mmol/L, pH0=2.5

2.3 PMS/Cr(VI)體系降解AO7

2.3.1 初始pH值對體系降解的影響 當(dāng)PMS溶于水時顯酸性,pH值可以達(dá)到3以下,為考察酸性條件在體系降解AO7中的作用,將PMS/Cr(VI)體系與酸性條件下單獨Cr(VI)降解AO7進(jìn)行對比,并調(diào)節(jié)不同初始pH值探究其對體系降解效果的影響,結(jié)果如圖5所示.初始pH值為2.5時Cr(VI)可以單獨降解AO7,降解效率與PMS/Cr(VI)體系降解效率相近,說明PMS/Cr(VI)體系降解AO7是由于PMS溶于水創(chuàng)造的酸性條件使得Cr(VI)具有強氧化性進(jìn)而直接氧化AO7;隨著pH值的升高AO7的降解率逐漸降低,pH值為4.5時AO7幾乎不降解,表明PMS/Cr(VI)降解AO7的反應(yīng)僅在3以下時效果較好.

2.3.2 自由基掩蔽劑對體系降解的影響 為驗證Cr(VI)是否能夠活化PMS產(chǎn)生活性自由基,使用叔丁醇作為×OH掩蔽劑,乙醇作為×OH及SO4·—的共同掩蔽劑進(jìn)行掩蔽實驗,結(jié)果如圖6所示.2種掩蔽劑對于體系降解均無明顯影響,說明Cr(VI)并不能活化PMS產(chǎn)生活性自由基,結(jié)合2.3.2實驗結(jié)果可以說明AO7的降解是酸性條件下Cr(VI)的強氧化性導(dǎo)致的.

圖5 不同初始pH值對AO7降解的影響

PMS=7.83mM, Cr(VI)=0.38mM, AO7=0.3mM

圖6 不同自由基掩蔽劑對AO7降解的影響

PMS=7.83mM, Cr(VI)=0.38mM, AO7=0.3mM, pH0=2.5

2.4 基于PMS的Cr(VI) -AO7協(xié)同處理機理

徐蕾[27]等人研究發(fā)現(xiàn),在常溫條件下Cl-可以與PMS發(fā)生非自由基反應(yīng)生成活性氯,其反應(yīng)方程如下:

2Cl-+ HSO5-+ H+= SO42-+ Cl2+ H2O (1)

Cl2+ H2O = HClO + H++ Cl-(2)

Cl-+ HSO5-= SO42-+ HclO (3)

本研究中2.2.3實驗結(jié)果驗證了這一機理,同時2.3實驗結(jié)果表明,Cr(VI)不能活化PMS產(chǎn)生活性自由基,而是由于PMS/Cl-體系創(chuàng)造的酸性條件使得Cr(VI)具有強氧化性,在氧化AO7的同時實現(xiàn)自身向低毒性Cr(III)的轉(zhuǎn)化.

由于在PMS/Cr(VI)/Cl-體系中Cr(VI)與活性物質(zhì)HClO均能降解AO7,因此可以通過計算兩部分對AO7降解的貢獻(xiàn)占比來確定體系中起主要作用的活性物質(zhì).計算過程如下:通過PMS/ Cr(VI)體系中AO7降解及Cr(VI)去除量計算得出單位濃度Cr(VI)消耗對應(yīng)的AO7降解量,再通過PMS/Cr(VI)/Cl-體系中Cr(VI)的消耗量計算得出對應(yīng)的AO7降解量,AO7的降解總量除去因Cr(VI)氧化降解的量剩余為HClO氧化降解的量;計算結(jié)果如下:PMS/ Cr(VI)/Cl-體系降解AO7的反應(yīng)中,HClO氧化降解的部分占70.8%,Cr(VI)氧化降解的部分占29.2%.

綜上所述,PMS/Cr(VI)/Cl-體系中AO7的降解是由于Cl-與PMS反應(yīng)產(chǎn)生氧化性物質(zhì)HClO以及PMS投加創(chuàng)造的酸性條件使得Cr(VI)具有強氧化性的共同作用,其中起主導(dǎo)作用的是HClO;Cr(VI)的轉(zhuǎn)化是由自身與AO7發(fā)生氧化還原反應(yīng)導(dǎo)致的.

2.5 中間產(chǎn)物、TOC測定及降解途徑分析

為探究PMS/Cr(VI)/Cl-體系降解AO7的途徑進(jìn)行中間產(chǎn)物的測定,測定結(jié)果見表1,根據(jù)測定結(jié)果推測的AO7降解途徑見圖7.

表1 中間產(chǎn)物測定結(jié)果

如圖7所示,反應(yīng)中AO7的-N=N-優(yōu)先被打開從而使染料脫色,AO7被分解為對氨基苯磺酸鈉及1-氨基-2-萘酚;隨后對氨基苯磺酸鈉可以被氧化成對苯酚及1,2,4苯三酚,同時磺基脫下形成甲基磺酸;1-氨基-2-萘酚可以被氧化形成1-硝基-2-萘酚及2-萘酚,隨后萘環(huán)被破壞生成多種苯系物;沿著對氨基苯磺酸鈉及1-氨基-2-萘酚2條路徑氧化最終均生成苯系物,且苯環(huán)無法進(jìn)一步被打開.

圖7 AO7可能的降解途徑

為探究體系降解AO7的礦化程度在反應(yīng)前后進(jìn)行TOC測定,測定結(jié)果反應(yīng)前后TOC無明顯變化,說明體系降解AO7無法達(dá)到礦化,與中間產(chǎn)物測定結(jié)果相同.

3 結(jié)論

3.1 單獨PMS在120min內(nèi)對AO7基本無降解,PMS/Cr(VI)、PMS/Cl-以及PMS/Cr(VI)/Cl-體系均可以有效降解AO7,120min時降解率分別達(dá)到58.8%、88.9%及97.9%;PMS/Cr(VI)以及PMS/Cr (VI)/Cl-體系中Cr(VI)去除率分別可達(dá)到35.9%及22.1%.

3.2 初始pH值對PMS/Cl-體系降解AO7無明顯影響.PMS/Cr體系在降解AO7的同時Cr(VI)自身可以轉(zhuǎn)化為Cr(III);隨著pH值降低AO7及Cr(VI)去除率逐漸升高,pH值在3以下反應(yīng)效果較好.

3.3 PMS/Cr(VI)/Cl-體系中AO7的降解主要是強氧化性物質(zhì)HClO以及Cr(VI)的共同作用,其中起主導(dǎo)作用的是HClO;Cr(VI)的轉(zhuǎn)化是由自身與AO7發(fā)生氧化還原反應(yīng)導(dǎo)致的.

3.4 反應(yīng)過程中AO7的-N=N-鍵首先被破壞從而使染料脫色,且隨著反應(yīng)進(jìn)行萘環(huán)可以被破壞但苯環(huán)無法被進(jìn)一步打開,體系反應(yīng)前后TOC值不變,不能達(dá)到礦化.

[1] 郭建博.高鹽染料廢水的生物降解及介提強化作用研究 [D]. 大連:大連理工大學(xué), 2005. Guo JB. Biodegradation of hyper-salinity dye wastewaters and the accelerating effect of redox mediators [D]. Dalian: Dalian University of Technology, 2005.

[2] 張祿艷,王 競,呂 紅,等.高鹽條件下染料酸性橙7的生物降解特性 [J]. 中國環(huán)境科學(xué), 2009,29(6):640-645. Zhang LY, Wang J, Lv H, et al. Biodegradation characteristics of Acid Orange 7under hypersaline conditions [J]. China Environmental Science, 2009,29(6):640-645.

[3] Liu W, Liu C, Liu L, et al. Simultaneous decolorization of sulfonated azo dyes and reduction of hexavalent chromium under high salt condition by a newly isolated salt-tolerant strain Bacillus circulans BWL1061 [J]. Ecotoxicology and Environmental Safety, 2017,141: 9-16.

[4] Hussain S, Quinn L, Li J, et al. Simultaneous removal of malachite green and hexavalent chromium by Cunninghamella elegans biofilm in a semi-continuous system [J]. International Biodeterioration & Biodegradation, 2017,125:142-149.

[5] Anwar F, Hussain S, Ramzan S, et al. Characterization of Reactive Red-120Decolorizing Bacterial Strain Acinetobacter junii FA10Capable of Simultaneous Removal of Azo Dyes and Hexavalent Chromium [J]. Water, Air, & Soil Pollution, 2014,225:1-16.

[6] 方 偉.改性石墨烯/聚吡咯復(fù)合材料對水中Cr(VI)及剛果紅的吸附研究 [D]. 廣州:華南理工大學(xué), 2018. Fang W. Research on Adsorption of hexavalent chromium and CongoRed in aqueous solutions onto modified graphene/pyrrole composite materials [D]. Guangzhou: South China University of Technology, 2018.

[7] Kyzas G Z, Lazaridis N K, Kostoglou M. On the simultaneous adsorption of a reactive dye and hexavalent chromium from aqueous solutions onto grafted chitosan [J]. Journal of Colloid And Interface Science, 2013,407:432-441.

[8] Fu F, Han W, Tang B, et al. Insights into environmental remediation of heavy metal and organic pollutants: Simultaneous removal of hexavalent chromium and dye from wastewater by zero-valent iron with ligand-enhanced reactivity [J]. Chemical Engineering Journal, 2013,232:534-540.

[9] Kim S A, Kamala-Kannan S, Oh S, et al. Simultaneous removal of chromium(VI) and Reactive Black 5using zeolite supported nano- scale zero-valent iron composite [J]. Environmental Earth Sciences, 2016,75:1-8.

[10] Xie W, Zhang M, Liu D, et al. Photocatalytic TiO2/porous BNNSs composites for simultaneous LR2B and Cr (VI) removal in wool dyeing bath [J]. Journal of Photochemistry and Photobiology A: Chemistry, 2017,333:165-173.

[11] Djellabi R, Ghorab M, Sehili T. Simultaneous Removal of Methylene Blue and Hexavalent Chromium From Water Using TiO2/Fe(III)/ H2O2/Sunlight [J]. CLEAN-SOIL AIR WATER, 2017:45.

[12] Suzuko Y, Atsushi Y, Hiroyuki A. Photocatalytic degradation of chloroform in the gas phase on the porous TiO2pellets: effect of Cl-accumulated on the catalyst surface [J]. Journal of Photochemistry and Photobiology A: Chemistry, 2005,169(2):191-196.

[13] Cardoso J C, Lizier T M, Zanoni M V B. Highly ordered TiO2nanotube arrays and photoelectrocatalytic oxidation of aromatic amine [J]. Applied Catalysis B: Environmental, 2010,99(1/2):96-102.

[14] Vogtenhuber D, Podloucky R, Redinger J. Ab initio study of atomic Cl-dsorption on stoichiometric and reduced rutile TiO2(110) surfaces [J]. Surface Science, 2000,(454-456):369-373.

[15] 古振川,高乃云,安娜,等.Cl-/PMS體系降解甲氧芐啶的效能與機理 [J]. 中國環(huán)境科學(xué), 2018,38(3):977-984. Gu Z C, Gao N Y, An N, et al. Efficiency and mechanism of trimethoprim degradation in Cl-/PMS system [J]. China Environmental Science, 2018,38(3):977-984.

[16] 張 珂,許 芬,陳家斌,等.丙酮/氯離子協(xié)同活化過一硫酸鹽降解酸性橙 [J]. 中國環(huán)境科學(xué), 2018,38(11):4159-4165. Zhang K, Xu F, Chen JB, et al. Acetone and chloride ion synergistically activate peroxymonosulfate to decolorize acid orange [J]. China Environmental Science, 2018,38(11):4159-4165.

[17] 談超群,董雨婕,鐘毅杰,等.新型氯離子活化過氧單硫酸鹽的非自由基系統(tǒng)去除水中撲熱息痛的研究 [J]. 四川大學(xué)學(xué)報(自然科學(xué)版), 2018,55(4):819-826. Tan C Q, Dong Y J, Zhong Y J, et al. Acetaminophen degradation with non-radical based reactive oxidants generated by chloride activated peroxymonosulfate system [J]. Journal of Sichuan University (Natural Science Edition), 2018,55(4):819-826.

[18] Liang C J, Bruell C J, Marley M C, et al. Persulfate oxidation for in situ remediation of TCE. I Activated by ferrous ion with and without a persulfate-thiosulfate redox couple [J]. Chemosphere, 2004,55(9): 1213-1223.

[19] Anipsitakis G P, Dionysiou D D. Degradation of organic contaminants in water with sulfate radicals generated by the conjunction of peroxymonosulfate with cobalt [J]. Environmental Science and Technology, 2003,37(20):4790-4797.

[20] Asadi A, Dehghani MH, Rastkari N, et al. Comparison of potentiality of Zinc oxide nanoparticles and hydrogen peroxide in removal of hexavalent chromium from polluted water [J]. Journal of Birjand University of Medical Sciences, 2012,19:277-285.

[21] GB/7467-87 水質(zhì)六價鉻的測定二苯碳酰二肼分光光度法 [S]. GB/7467-87 Water quality-Determination of chromium(VI) - 1,5diphenylcarbohydrazide spectrophotometric method [S].

[22] Betterton E A, Hoffmann M R. Kinetics and mechanism of the oxidation of aqueous hydrogen sulfide by peroxymonosulfate [J]. Environmental Science and Technology, 1990,24(12):1819-1824.

[23] 葛勇建,蔡顯威,林 翰,等.堿活化過一硫酸鹽降解水中環(huán)丙沙星 [J]. 環(huán)境科學(xué), 2017,38(12):5116-5123. Ge Y J, Cai X W, Lin H, et al. Base activation of peroxymonosulfate for the degradation of ciprofloxacin in water [J]. Environmental Science, 2017,38(12):5116-5123.

[24] Wang Z H, Yuan R X, Guo Y G, et al. Effects of chloride ions on bleaching of azo dyes by Co2+/oxone regent: Kinetic analysis [J]. Journal of Hazardous Materials, 2011,190(1–3):1083-1087.

[25] Deborde M, Gunten U V. Reactions of chlorine with inorganic and organic compounds during water treatment-Kinetics and mechanisms: A critical review [J]. Water Research, 2008,42(1/2):13-51.

[26] Yang S Y, Wang P, Yang X, et al. Degradation efficiencies of azo dye Acid Orange 7by the interaction of heat,UV and anions with common oxidants: Persulfate, peroxymonosulfate and hydrogen peroxide [J]. Journal of Hazardous Materials, 2010,179:552-558.

[27]徐 蕾,袁瑞霞,郭耀廣,等.氯離子對鈷/單過氧硫酸鹽體系降解2,4,6-三氯苯酚的影響 [J]. 武漢大學(xué)學(xué)報理學(xué)版, 2013,59(1):51- 56. Xu L, Yuan R X, Guo Y G, et al. Effects of chloride ions on degradation of 2,4,6-trichlorophenol by Co(II)/peroxymonosulfate (Co/PMS) system [J]. Journal of Wuhan University (Natural Science Edition), 2013,59(1):51-56.

Synergistic treatment effect and mechanism of Cr(VI)-dye complex wastewater based on PMS.

YAN Song1,2, ZHANG Cheng-wu1,2, LI Tian-yi1,2, QIN Chuan-yu1,2*

(1.Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun 130012, China；2.College of New Energy and Environment, Jilin University, Changchun 130012, China)., 2019,39(8)：3271~3276

This article investigated the feasibility, influencing factors and mechanism of the synergistic treatment of azo dyes II (AO7) and Cr (VI) by adding persulfate (PMS). The results showed that the system could reduce the Cr (VI) and remove AO7 simultaneously and the degradation rate reached 97.9% and 22.1% at 120 minutes, respectively. AO7 degradation and Cr (VI) removal efficiency increased gradually with the decrease of initial pH. The degradation of AO7 was mainly because of the combined functions of the oxidizing substance HClO produced when Cl-reacts with PMS and the strong oxidizer Cr (VI) in acidic condition created by PMS. Among these two functions, HClO played the dominant role. In addition, the conversion of Cr (VI) was caused by the redox reaction between itself and AO7. Thus, this research could provide a theoretical basis for the treatment of compound polluted wastewater.

dye wastewater；compound pollution；persulfate；Cr(VI)；synergistic treatment

X703

A

1000-6923(2019)08-3271-06

閆 松(1995-),女,內(nèi)蒙古興安盟烏蘭浩特人,吉林大學(xué)新能源與環(huán)境學(xué)院環(huán)境工程專業(yè)工程學(xué)士,主要從事水土污染控制與修復(fù)方面的研究.發(fā)表論文1篇.

2019-02-25

國家自然科學(xué)基金資助項目(41572213,41530636)

* 責(zé)任作者, 副教授, qincyu@jlu.edu.cn