用掺硼金刚石(BDD)电极的电化学氧化协同作用和臭氧(O3)的工业废水处理

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电化学氧化与芬顿技术降解三氯生的研究进展

电化学氧化与芬顿技术降解三氯生的研究进展曾湘梅【摘要】三氯生(TCS)作为一种高效的广谱抗菌剂,被广泛应用于各种药品及个人护理用品中.随着三氯生的大量使用,在水环境中频繁被检出的同时,也发现其在一定条件下,还发现其会转化成其他致癌物及多种有毒有害物质,这将给生态系统安全和平衡带来了极大的隐患.常规的污水处理工艺对三氯生的降解都很有限.高级氧化技术能高效降解三氯生,且能在降解后大大提高三氯生的可生化性.在对目前常用于降解三氯生的电化学氧化和芬顿技术介绍的基础上,并从各种技术的机理,处理效果,目前存在的问题等方面对每种氧化技术进行阐述,并对其广泛应用于工业化处理提出展望.【期刊名称】《有色冶金设计与研究》【年(卷),期】2017(038)002【总页数】4页(P46-49)【关键词】污水处理;三氯生;电催化高级氧化技术;芬顿【作者】曾湘梅【作者单位】中冶赛迪工程技术股份有限公司,重庆市400013【正文语种】中文【中图分类】X703包括三氯生在内的一大类新兴的化学物质具有潜在危害,从而引起人们的广泛关注,这些化学品包括药物和个人护理用品 (pharmaceuticals and personal careproducts,简称PPCPs)[1]。

直到1999年在美国环境保护总署(EPA)支持下,Daugh ton和Ternes (1999)[2]发表了一篇关于药品及个人护理用品的综述文章,PPCPs污染才得以正式被提出[1]。

三氯生(TCS)作为药品与个人护理品(PPCPs)中的添加物,是一种国际流行的广谱抗菌剂。

由于它们与皮肤有极好的相容性,对革兰氏阳性菌、革兰氏阴性菌、真菌、酵母菌、病毒等也都有高效抑杀作用,因此被广泛应用于纺织品、塑料、肥皂、化妆品、牙膏和伤口消毒剂等类产品中,起到杀菌、抑菌和除臭的作用[3]。

三氯生是一种潜在的持久性有机污染物(Persistent organic pollutants,POPS),其亲水性低,亲脂性强,pH为7时,log Kow为4.8[4],物理化学性质稳定,在环境中较难降解。

掺硼金刚石薄膜电极处理苯酚废水试验研究

第４０卷第１０期２０１４年４月
山西建筑
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文章编号：１００９－６８２５（２０１４）１０ — ０１２３ — ０３
苯酚初始浓度分别为２５ｍｇ／Ｌ，５０ｍｇ／Ｌ，１００ｍｇ／Ｌ，１５０ｍｇ／Ｌ，
电流密度为５５ｍＡ／ｃｍ，电解质硫酸钠浓度为５．０ｓ／Ｌ，电解时间为１８０ａｉｒｎ时，ｕＶ：。和ＣＯＤ随电解时间的变化曲线如图２所示。
型直流电源提供，利用磁力搅拌器保证废水充分混合。试验废水８０ｍＡ／ｅｍ，苯酚废水浓度为１００ｍｇ／Ｌ，电解质浓度为５ｇ／Ｌ时，为人工模拟苯酚废水。试验装置示意图如图１所示。ｕＶ。和ＣＯＤ随电解时间的变化曲线如图３所示。由图３ａ），图
化肥厂外排废水等废水方面处理效果良好。掺硼金刚石薄膜
电极具有很高的机械强度，化学稳定性和优良的电化学性能，即
使在高强度电流负荷下作用电极表面也不会发生明显变化，具有很宽的电化学窗口和较低的背景电流，尤其表现较高的过氧化电位Ｊ。电化学氧化法耗电量极大，限制了其工业化应用。高云芳
— — —
—
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（１）

掺硼金刚石薄膜电极在水处理中应用的研究进展_方宁

可以被完全矿化 , 原液所需能耗和时间分别为 80 kW · h/ m3 、4 h ;经过预处理的渗滤液所需能耗和时间分别为 61 kW · h/ m3 、3 h[ 25] 。 2 .1 .3 染料用 BDD 薄膜电极电解还原酸性橙 Ⅱ的过程中 , 偶氮键(N =N)断裂生成小分子电解产物后 , 继续被矿化。在酸性介质中 , 还原产物(苯胺)以铵正离子的形态存在 , 不易被继续降解 ;在碱性介质中 , 酸性橙 Ⅱ降解为苯胺后继续被矿化成 CO 2 和 H 2 O ;当支持电解质中存在氯离子时 , 电化学氧化过程生成次氯酸根离子 , 次氯酸根离子的存在 , 加速了酸性橙 Ⅱ 的降解[ 26] 。文献[ 27] 考察研究了 BDD 薄膜电极对活性艳红的处理效果。通过循环伏安扫描 , 发现其比石墨电极和 P t 电极的响应电流大 , 石墨电极和 P t 电极响应几乎没有 , 说明 BDD 薄膜对活性艳红具有一定的降解能力。但是经过连续扫描 3 次以后 , 其响应电流峰值变小 , 究其原因是由于表面钝化所导致。 2 .1 .4 除草剂复杂的有机氯除草剂如敌草隆(3-(3 , 4-二氯苯基)-1 , 1-二甲基脲)、3 , 4-二氯苯胺[ 28] 、4-氯-2-甲基苯氧基乙酸、2-(4-氯代苯氧基)-2-甲基丙酸和 2-(4-氯2-甲基苯氧基)丙酸[ 29] 等在 BDD 薄膜电极上也表现出了较好的降解效果。降解过程中苯环断裂 , 有氯离子、铵离子和中间产物小分子有机酸生成。在较低的反应物浓度下 , 其电流效率仍然能大于 20 %。 2 .1 .5 表面活性剂对于大分子表面活性剂 , 用十二烷基苯磺酸纳和十六烷基三甲基铵氯化物作为目标物[ 30] , 在 BDD 薄膜电极表面上的电化学氧化表明 , 十二烷基苯磺酸纳(阳离子)平均电流效率为 6 %, 十六烷基三甲基铵氯化物(阴离子)平均电流效率为 12 %。 2 .1 .6 羧酸羧酸在 BDD 薄膜电极上的电化学氧化有苯甲酸[ 31] , 在电解过程中生成水杨酸、氢醌和羟基苯甲酸等中间产物 , 而后进一步被降解为 H 2 O 和 CO 2 。对于芳香族化合物来说 , 电流效率的高低主要受传质的影响 , 降解速率受传质的控制 , 由于反应物是大分子有机物 , 在电极表面往往要分好几步才能被彻底矿化 , 因此中间产物的生成不能忽视。有些中间产物在溶液中生成不溶性聚合物 , 当电压较小时 , 容易在电极表面聚合而使电极钝化。溶液中存在一些可被氧化的阴离子与主反应竞争 , 从而降低电流效率。

硼掺杂金刚石膜电极电氧化降解对氯苯酚废水

Ｐ— ｈｏｏｈｎｌｙｌｃｒｃｅｉａｏｉａｉｎｓｒｐｓｄｃｌｒｐｅｏｂｅｅｔｏｈｍｃｌｘｄｔｏｉｐｏｏｅｗｉＢＤＤａｏｅｔｈｎｄ．Ｔｈｅｆｃｓｏｆｔｃｎｌｉａｅｆｅｔｅｈｏｏｇｃｌｐｒｅｅｓａｅｉｖｓｉａｅａａｔｒｎｅｔｇｔｄｗｈｉｈｉｃｕｅｔｅａｏｃｃｒｅｔｄｎｉ，ｈｎｔａｏｅｔａｉｎｏ－ｈｏｏｈｎｌ，ｍｒｃｎｌｄｈｎｄｉｕｒｎｅｓｔｔｅｉｉｉｌｎｃｎｒｔｏｆｐｃｌｒｐｅｏｙｃ
Ｖｖ．ｃ）（ｓＥ时，ＢＤ膜电极能够良好地电氧化降解对氯苯酚溶液，该过程是通过直接电氧化过程与间接电氧化过程联ｓＤ
合作用实现的。通过考察若干工艺因素对对氯苯酚电氧化降解效果的影响发现，较为理想的工艺参数组合为，阳极电流密度６ｏ０ｍＡ－ｍ～、支持电解质浓度ｌ．一、对氯苯酚初始浓度ｌ０Ｌｇ０ｍｍｏ・一、电解液初始ｐ。在该工艺条件下，ｌＬＨ７
ｄａｎＢＤＤ）ｆｍｌｃｒｄｅｔａｍｅｉｍｙｃｃｉｖｌｍｍｅｒ．ｅｅｈｏｏｙｆｒｅｒｄｔｎｏｉｍｏｄ（ｉｅｅｔｏｅｉｎｕｒｌｄｕｂｙｌｏｔｌｎｃａｔＡｎｗｔｃｎｌｇｏｇａａｉｆｙｄｏ
ＣＯＤ去除率达到９％，平均电流效率为５％。高效液相色谱证实了Ｂ６１０２ＤＤ膜电极能有效地电氧化降解对氯苯酚。关键词：硼掺杂金刚石薄膜电极：对氯苯酚；电氧化；降解；废水中图分类号：０６３７１；Ｘ７３１０文献标识码：Ａ

金刚石膜电极电化学氧化工业含磷废水的研究

不会产生电极中毒现象．
物，是由于有机废水成分复杂，但毒性大，ＯＣＤ值高，ｐＨ值变化大，机物浓度高，生物处理法受到多有使
种因素的制约，效果不佳．如何及时有效的处理这类废水已成为环保及工业界关注的焦点．金刚石膜作电极对于大多数有机物具有催化氧化作用，它进行电化学催化高级氧化技术（ＥＰ用ＡＯ）
ｂｒｎｄｐｄｄａｎＢｏｏ — ｏｅｉｍｏｄ（ＤＤ）ｔｉｌｅｅｔｄｓｔｘｌｒｅｉｆｕｎｅｆｈｉ，ａｋｖｌｇｎｈｉｔｎｅｏｌｃｈｎｆｍｌｃｒｅｏｅｐｏｅｔｎｌｅｃｓｏｅｔｉｏｈｔｍｅｔｎｏｔｅａｄｔｅｄｓａｃｆｅｅ— ａ
化学需氧量（Ｏ降解率的影响．ＣＤ）实验发现在槽电压８电极间距２ｍ经过５Ｖ、ｍ，ｈ电解废水的ＣＤ降解率达到了Ｏ９．％，３９并且做了阴极替换实验，后对ＣＤ的降解机理做了分析．最Ｏ
ｗａｔｗａｅｙｄａｏｌｌｃｒｄｓｅｔｒｂｉｍｎｄｆｍｅｅｔｏｅｉ
ＺＨＵ — ｏｇ，ＣＨＡＮＧｎＹａｄｎＭｉｇ，ＷＡＮＧｉｇＬｎ
（ｃｏｌｆｌｃｏｉＩｆｍｔｎａｄＣｍｕｉｔｎＥｇｎｅｎ，ｉｊｎｖｒｔｏＴｃｎｌｙＴａｊ０１１ｈａＳｈｏｏＥｅｔｎｎｏａｉｎｏｍｎａｏｎｉｅｒｇＴａｉＵｉｓｙｆｅｈｏｇ，ｉｉ３０９，Ｃｉ）ｒｃｒｏｃｉｉｎｎｅｉｏｎｎｎ

污水处理高级氧化技术

污水处理高级氧化技术近年来，由于工业化发展的速度较快，致使工业企业的污水排放量剧增，造成的环境污染问题越来越严重。

在工业生产排放的废水中，有机废水的浓度较高、成分繁杂，且具有难降解、含毒性物质等特征。

因此，传统的污水处理技术已无法满足当今的污水处理要求，所以，有效处理此类工业废水已成为当务之急。

目前，先进的高级氧化法处理效果好、反应速度快、二次污染概率小且适用范围广。

因此，该技术已逐步应用于各种工业废水处理工艺中。

该技术按反应原理划分可分为臭氧氧化、光化学氧化、催化湿式氧化、电化学氧化、芬顿氧化等。

1、高级氧化法处理废水的研究进展1.1 臭氧氧化（1）臭氧氧化按照对污染物和臭氧的化学反应方式的不同，可分成二类。

一类是用臭氧直接和有机化合物反应，一般称为臭氧直接反应；另一类是臭氧先经过分解形成羟基自由基，再通过羟基自由基和有机产物进行直接化学反应，一般称为臭氧发生器间接化学反应。

在实际应用中，与臭氧的直接反应通常是通过打破有机物的双键结合，将大分子有机质转变为小分子，但总体氧化程度并不高，而破碎成小分子的有机物具备了较大的可生化性。

臭氧直接氧化是由于其选择能力较强、化学反应速度慢、以及对污染物的全面净化难度较大等特点，但可以对工业废水进行预处理，以此提高废水的B/C比。

而臭氧的间接处理化学反应基本原理为：臭氧在水体内先溶解形成羟基自由基（OH），然后羟基自由基再去氧化有机物。

该方法一般不具备化学选择性，但由于反应速度快、氧化程度高、污水处理效率好等优点，在工业废水处理中取得了较普遍的运用。

在臭氧处理间接化学反应中，臭氧在水体形成羟基自由基主要采用两种路径：①在碱性条件下，臭氧迅速溶解形成羟基自由基，且在紫外线光的影响下，臭氧形成羟基自由基；②在各种金属催化的影响下，臭氧形成羟基自由基。

国内学者对催化剂展开研究，以负载式二氧化钛为催化剂，对臭氧化合物在强催化作用下氧化对水溶性元素腐殖酸的影响开展了深入研究，结果显示，利用二氧化物能够增加对臭氧的氧化效果，其效果增加到了29.1%，而最终的腐植酸氧化物去除率更高达84.9%。

用掺硼金刚石（BDD）电极的电化学氧化协同作用和臭氧（O3）的工业废水处理

⽤掺硼⾦刚⽯（BDD）电极的电化学氧化协同作⽤和臭氧（O3）的⼯业废⽔处理Synergy of electrochemical oxidation using boron-doped diamond (BDD)electrodes and ozone (O 3)in industrial wastewater treatmentM.A.García-Morales a ,G.Roa-Morales a ,?,Carlos Barrera-Díaz a ,Bryan Bilyeu b ,M.A.Rodrigo ca Centro Conjunto de Investigación en Química Sustentable,UAEM-UNAM,Carretera Toluca-Atlacomulco,Km 14.5,Campus San Cayetano,C.P.50200,Toluca Estado de México,Mexicob Department of Chemistry,Xavier University of Louisiana,New Orleans 70125,LA,USAcDepartment of Chemical Engineering,Facultad de Ciencias Químicas,Universidad de Castilla-La Mancha,Campus Universitario s/n 13071Ciudad Real,Spaina b s t r a c ta r t i c l e i n f o Article history:Received 9October 2012Received in revised form 22October 2012Accepted 23October 2012Available online 27October 2012Keywords:Electrooxidation Ozone BDDWastewater CODO 3-BDD coupled processThis work evaluates the coupling of electrochemical oxidation and ozonation to reduce the high organic load of industrial wastewater quickly and effectively.Ozonation alone is shown to only reduce the COD of waste-water by about45%.Electrochemical oxidation using boron-doped diamond electrodes reduces the COD by 99.9%,but requires over 2h per 0.7L batch.However,when the two processes are coupled,the COD is re-duced by 99.9%along with most color and turbidity in about an hour.The coupled process practically elimi-nates the COD,color,and turbidity without the addition of chemical reagents or changing the pH and doesn't generate any sludge,so it is both effective and environmentally friendly.2012Elsevier B.V.All rights reserved.1.IntroductionIndustrial ef ?uents are dif ?cult to treat using traditional biological systems due to the high variations in their compositions.Unlike munic-ipal wastewater,industrial sources have higher organic load,color,and pH which ?uctuate[1,2].While traditional biological reactors are very effective in digesting the organic matter in municipal wastewater into carbon dioxide and water,the effectiveness drops considerably when treating industrial wastewater.Biological reactors typically only reduce 50%of the biochemical oxygen demand (BOD 5)and 35%of the chemical oxygen demand (COD)[3,4]. Due to the limitations of biological reactors,industrial wastewater is typically pretreated using physical –chemical processes such as co-agulation –?occulation.However,these processes generate large quantities of sludge and usually require pH adjustments and chemical reagents,all of which create their own environmental issues [5,6].Co-agulation –?occulation is not ef ?cient in the removal of dissolved (persistent)chemical pollutants.In recent works we have shown that combining electrocoagulation and ozone produces synergistic effects in wastewater treatment [7,8].However,the use of electrooxidation with boron-doped diamond (BDD)electrodes in conjunction with ozone for treating industrial ef ?u-ents has not yet been reported.Both electrooxidation and ozonation are advanced oxidative pro-cesses based on the generation of hydroxyl radicals (OH ),which have high oxidation potential and degrade of a wide range of contam-inants.In particular,BDD electrodes have high anodic stability,a wide working potential window,and low stable voltammetric background current in aqueous media[9,10].Therefore,the electrochemical be-havior of BDD electrodes have been investigated with the goal of de-veloping applications for wastewater treatment [11,12].On the other hand,ozonation is an ef ?cient and powerful oxidizing process wellknown for its degradation of organic compounds.The limitations to these processes are the time required for electrooxidation and the ef-fectiveness of ozonation,so neither alone is truly industrially practical.Thus,this study evaluates the synergy of the two processes com-pared to the ef ?ciency and effectiveness of the individual ones.The effectiveness is evaluated in terms of color,turbidity and chemical ox-ygen demand (COD)reduction.The in ?uence of operating parame-ters such as time of treatment,current density,and initial pH is also evaluated.2.Materials and methods 2.1.Wastewater samplesWastewater samples were collected from the treatment plant of an industrial park,which receives the discharge of144different facil-ities.Therefore,the chemical composition of this ef ?uent is ratherElectrochemistry Communications 27(2013)34–37Corresponding author.Tel.:+527222173890;fax:+527222175109.E-mail address:groam@uaemex.mx (G.Roa-Morales).1388-2481/$–see front matter ?2012Elsevier B.V.All rights reserved./10.1016/j.elecom.2012.10.028Contents lists available at SciVerse ScienceDirectElectrochemistry Communicationsj o ur n a l h o m e p a g e :w w w.e l s e v i e r.c o m /l o c a t e /e l e c o mcomplex.Samples were collected in plastic containers and cooled down to4°C,then transported to the laboratory for analysis and treatment.The pH of the raw wastewater is8.24and all treatment and testing were done at this value.2.2.Electrooxidation reactorA batch cylindrical electrochemical reactor was set up for the elec-trochemical process.The reactor cell contains a pair of BDD electrodes (BDD?lm supported on a niobium substrate),each electrode was 20.0cm by2.5cm with a surface areaof50cm2.Batch volumes of 0.70L were treated in the1.00L reactor.A direct-current power source supplied the systemwith0.5,1.0,and1.5A,corresponding to current densities of10,20,and30mA/cm2.2.3.Ozonation reactorThe ozone experiments were conducted in a1.5L glass reactor at18°C.Ozone was supplied by a Paci?c Ozone Technology generator. The gas was fed into the reactor through a porous plate situated at the reactor bottom.The ozone concentration at the gas inlet and out-let of the reactor was measured by redirecting the?ow to a series of ?asks containing0.1M potassium iodide.The mean concentration of ozone in the gas phase was5±0.5mg/L and was measured imme-diately before each run.Ozonation experiments were carried out at the pH of raw wastewater and samples were taken at regular inter-vals to determine COD.2.4.Synergy of electrooxidation/O3processFor the combined system the pair of BDD electrodes from the electrooxidation reactor was installed in the ozonereactor.Ozone was introduced at the same rate and the BDD electrodes were given the same current densities as in the individual reactors.Treated sam-ples were taken at the same intervals and were analyzed in the same way.2.5.Methods of analysisThe initial evaluations of the electrochemical,ozonation,and inte-grated treatments were determined by analysis of theCOD(mg/L), color(Pt–Co scale),and turbidity(NTU scale).COD was determined by the open re?ux method according to the American Public Health Association(APHA).Following this method,samples are re?uxed with potassium dichromate and sulfuric acid for2h.Once the opti-mal conditions were found the raw and treated wastewater samples were analyzed using the standard methods for the examination of water and wastewater procedures.[13].3.Results and discussion3.1.Electrooxidation treatmentThe COD reduction(%)as function of electrooxidation treatment time on the raw wastewater is shown in Fig.1.The maximum COD re-duction of99.9%was observed at140min of treatment.3.2.Ozonation treatmentOzone was introduced into the sample at a concentration of5±0.5mg/L and the COD was measured as a function of time.As shown in Fig.2,the maximum COD reduction was45%at120min of treatment time.3.3.Synergy of electrooxidation/O3processThe effect of coupling electrooxidation and ozonation processes was studied through a series of experiments using the COD reduction as a function of treatment time for the raw wastewater.In Fig.3the effect of variation on the current density values is also described. The maximum COD reduction of99.9%occurs at60min.A comparative graph of the COD reduction as a function of treat-ment time among the three treatments indicates that ozone is not as effective and electrooxidation takes longer than the coupled pro-cess(Fig.4).The UV–vis spectra of the raw and treated wastewater are shown in Fig.5.The raw wastewater shows considerable absorbance in the visible range of300to630nm which con?rms that it is highly col-ored.However,this color is effectively removed by the coupled treatment.The reduction in the values of some physicochemical parameters of the raw and treated wastewater is shown in Table1.As shown in Table1,the coupled process reduces and practically eliminates the organic pollutants in the wastewater.The high levels of COD,color,and turbidity are effectively reduced without any addi-tion of chemical reagents and without adjusting the pH.The coupled process also increases the ef?ciency of the organic removal by reduc-ing the treatment time.Thus the two processes act synergistically in the coupled process.Previous research[14]indicates that the oxidation of organics with concomitant oxygen evolution assumes that both organicoxidation Fig.1.COD removal as a function of electrooxidation treatment time at10mA/cm2.Fig.2.COD removal as a function of ozonation(5±0.5mg/L)treatment time.35M.A.García-Morales et al./Electrochemistry Communications27(2013)34–37and oxygen evolution take place on a BDD anode surface via intermedi-ation of hydroxyl radicals,generated from the reaction with water shown in Eqs.(1)and (2):BDD tH 2O →BDD eOH ?TtH ttee1TBDD eOH ?TtR →BDD tmCO 2tnH 2O :e2TReaction (2)is in competition with the side reaction of hydroxyl radical conversion to O 2without any participation of the anode sur-face as indicated in Eq.(3)BDD eOH ?T→BDD t1=2O 2tH tte ?:e3TThe ozone contribution can be attributed to the electrophilic na-ture of the direct attack by O 3molecules (Eq.(5))and the indirect at-tack via OH ?radicals in the ozonation process (Eq.(6)).According to Tomiyasu et al.[15]the ozonation effect may be ini-tiated by the following reactions:O 3tH 2O →2HO ?tO 2e4TO 3tOH →O ?2?tHO ?2e5TO 3tOH ?→HO ?2tO 2:e6TAccording to the literature,the pH value of the solution signi ?-cantly in ?uences ozone decomposition in water since basic pH causes an increase of ozone decomposition.At pH b 3hydroxyl radicals do not in ?uence the decomposition of ozone.For 7b pH b 10,the typical half-life of ozone is 15to 25min.[16].4.ConclusionsThe combination of electrooxidation and ozonation processes re-sults in a synergy that greatly enhances the rate and extent of remov-al of COD,color,and turbidity from a chemically complex industrial ef ?uent.Electroxodiation alone reduces the COD to less than 1%of the initial,but requires a relatively long time of 140min.On the other hand,ozonation alone only reduces it to 45%.When the coupled electrooxidation –ozonation process is used a maximum 99.9%of COD is removed in only 60min under the optimal conditions:pH 8.24,with 5±0.5mg/L of ozone concentration,and 30mA/cm 2of current density.While electrooxidation ef ?ciency usually increases with in-creasing current density,the coupled process is more ef ?cient at a rel-atively low (mA/cm 2)current density.AcknowledgmentsThe authors wish to acknowledge the support given by the Centro Conjunto de Investigación en QuímicaSustentable,UAEM-UNAM,and ?nancial support from the CONACYT through the projects 168305and 153828is greatlyappreciated.Fig.3.COD removal when coupling electrooxidation and ozonation processes at three different current densities (▲)30mA/cm 2(○)20mA/cm 2(?)10mA/cm 2.Fig.4.COD removal as a function of treatment time of (?)coupled,(Δ)electrooxidation and (■)ozonetreatment.Fig.5.UV –vis spectra of the (——)raw and (----)treated industrial wastewater.The parameters of the coupled treatment were 30mA/cm 2and 5±0.5mg/L of ozone.Table 1Physicochemical parameters of the raw and treated industrial wastewater.Parameter Raw wastewater Treated wastewater COD/mg L ?1534b 1Color/Pt –Co units 880b 50Turbidity/NTU52b 536M.A.García-Morales et al./Electrochemistry Communications 27(2013)34–37References[1] C.A.Martinez,E.Brillas,Applied Catalysis B:Environmental87(2009)105.[2] C.Barrera-Díaz,F.Ure?a-Nu?ez,E.Campos,M.Palomar-Pardavé,M.Romero-Romo,Radiation Physics and Chemistry67(2003)657.[3]V.Agridiotis,C.Forster,C.Balaboine,C.Wolter,C.Carliell-Marquet,Water Envi-ronment Journal20(2006)141.[4] C.J.Van der Gast,B.Jefferson,E.Reid,T.Robinson,M.J.Bailey,S.J.Judd,I.P.Thompson,Environmental Microbiology8(6)(2006)1048.[5] F.Hana?,O.Assobhei,M.Mountadar,Journal of Hazardous Materials174(2010)807.[6] C.Barrera-Díaz,I.Linares-Hernández,G.Roa-Morales,B.Bilyeu,P.Balderas-Hernández,Industrial and Engineering Chemistry Research48(2009)1253. [7]L.A.Bernal-Martinez, C.Barrera-Díaz, C.Sólis-Morelos,R.Natividad-Rangel,Chemical Engineering Journal165(2010)71.[8]M.A.García-Morales,G.Roa-Morales,C.Barrera-Díaz,P.Balderas-Hernández,Journal of Environmental Science and Health,Part A47(2012)22.[9]J.Sun,H.Lu,L.Du,H.Lin,H.Li,Applied Surface Science257(2011)6667.[10] F.L.Migliorini,N.A.Braga,S.A.Alves,nza,M.R.Baldan,N.G.Ferreira,Journalof Hazardous Materials192(2011)1683.[11]M.Panizza,P.A.Michaud,G.Cerisola,ninellis,Electrochemistry Communi-cations3(2001)336.[12] A.Morao,A.Lopes,M.T.Pessoa de Amorim,I.C.Goncalves,Electrochimica Acta49(2004)1587.[13]APHA,AWWA,Standard Methods for the Examination of Water and Wastewater,16th edition American Public Health Association,Washington DC,1995.[14] A.Kapalka,G.Fóti,ninellis,Electrochimica Acta53(2007)1954.[15]H.Tomiyasu,H.Fukutomi,G.Gordon,Inorganic Chemistry24(1985)2962.[16] B.Kasprzyk,M.Ziolek,J.Nawrocki,Applied Catalysis B:Environmental46(2003)639.37M.A.García-Morales et al./Electrochemistry Communications27(2013)34–37。

bdd电催化氧化处理

bdd电催化氧化处理
BDD电催化氧化处理是一种高级氧化技术，将电作为催化剂，以双氧水、氧气、臭氧等作为氧化剂而进行的氧化反应。

BDD电极是电化学降解技术中最核心的部分之一，掺硼金刚石薄膜（BDD）电极因其优异的性能成为近期应用研究焦点。

BDD电催化氧化法是一种有效的水处理技术，可用于降解有机物、去除有毒物质和杀灭细菌等。

该技术基于钻石电极的电化学氧化特性，通过施加电势使钻石电极上产生一系列具有强氧化能力的离子，从而实现对水中有机物和有毒物质的降解和去除。

BDD电催化氧化法的工作原理是通过施加一定的电势使钻石电极上产生氢氧根离子(OH-)、氧气和其他具有氧化能力的离子。

这些离子通过一系列氧化还原反应将有机物氧化为无害的物质，从而达到水处理的目的。

同时，BDD电极表面的高导电性使得电子的输运速度加快，有助于提高电化学反应的速率和效率。

BDD电催化氧化法的应用十分广泛。

在环境领域，它可以应用于废水处理、水资源再生利用和地下水修复等。

通过该技术可以降解和去除各种有机物，如苯系化合物、农药、染料和有机溶剂等。

同时，它还可以去除水中的重金属离子、有机酸和其他有毒物质，从而提高水质和保护环境。

此外，BDD电催化氧化法还可以用于消毒和杀菌。

与传统的消毒方法相比，该技术无需添加化学药剂，无毒性且能够对抗抗药性微生物，具有很大的应用潜力。

在实际应用中，BDD电极的规模化生产和商业化应用仍存在一定困难，且钻石电极表面的积碳现象也会降低其催化性能。

因此，需要进一步研究发展更经济、可持续和高效的BDD电催化氧化技术。

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Both electrooxidation and ozonation are advanced oxidative processes based on the generation of hydroxyl radicals (OH•), which have high oxidation potential and degrade of a wide range of contaminants. In particular, BDD electrodes have high anodic stability, a wide working potential window, and low stable voltammetric background current in aqueous media [9,10]. Therefore, the electrochemical behavior of BDD electrodes have been investigated with the goal of developing applications for wastewater treatment [11,12]. On the other hand, ozonation is an efﬁcient and powerful oxidizing process well known for its degradation of organic compounds. The limitations to these processes are the time required for electrooxidation and the effectiveness of ozonation, so neither alone is truly industrially practical.
Electrochemistry Communications 27 (2013) 34–37
Contents lists available at SciVerse ScienceDirect
Electrochemistry Communications
journal homepage: /locate/elecom
Synergy of electrochemical oxidation using boron-doped diamond (BDD) electrodes and ozone (O3) in industrial wastewater treatment
M.A. García-Morales a, G. Roa-Morales a,⁎, Carlos Barrera-Díaz a, Bryan Bilyeu b, M.A. Rodrigo c
article info
Article history: Received 9 October 2012 Received in revised form 22 October 2012 Accepted 23 October 2012 Available online 27 October 2012
a Centro Conjunto de Investigación en Química Sustentable, UAEM-UNAM, Carretera Toluca-Atlacomulco, Km 14.5, Campus San Cayetano, C.P. 50200, Toluca Estado de México, Mexico b Department of Chemistry, Xavier University of Louisiana, New Orleans 70125, LA, USA c Department of Chemical Engineering, Facultad de Ciencias Químicas, Universidad de Castilla-La Mancha, Campus Universitario s/n 13071 Ciudad Real, Spain
Keywords: Electrooxidation Ozone BDD Wastewater COD O3-BDD coupled process
abstract
This work evaluates the coupling of electrochemical oxidation and ozonation to reduce the high organic load of industrial wastewater quickly and effectively. Ozonation alone is shown to only reduce the COD of wastewater by about 45%. Electrochemical oxidation using boron-doped diamond electrodes reduces the COD by 99.9%, but requires over 2 h per 0.7 L batch. However, when the two processes are coupled, the COD is reduced by 99.9% along with most color and turbidity in about an hour. The coupled process practically eliminates the COD, color, and turbidity without the addition of chemical reagents or changing the pH and doesn't generate any sludge, so it is both effective and environmentally friendly.
2. Materials and methods
2.1. Wastewater samples
Wastewater samples were collected from the treatment plant of an industrial park, which receives the discharge of 144 different facilities. Therefore, the chemical composition of this efﬂuent is rather
Due to the limitations of biological reactors, industrial wastewater is typically pretreated using physical–chemical processes such as coagulation–ﬂocculation. However, these processes generate large quantities of sludge and usually require pH adjustments and chemical reagents, all of which create their own environmental issues [5,6]. Coagulation–ﬂocculation is not efﬁcient in the removal of dissolved (persistent) chemical pollutants.
In recent works we have shown that combining electrocoagulation and ozone produces synergistic effects in wastewater treatment [7,8]. However, the use of electrooxidation with boron-doped diamond (BDD) electrodes in conjunction with ozone for treating industrial efﬂuents has not yet been reported.
M.A. García-Morales et al. / Electrochemistry Communications 27 (2013) 34–37
35ቤተ መጻሕፍቲ ባይዱ
complex. Samples were collected in plastic containers and cooled down to 4 °C, then transported to the laboratory for analysis and treatment. The pH of the raw wastewater is 8.24 and all treatment and testing were done at this value.
Thus, this study evaluates the synergy of the two processes compared to the efﬁciency and effectiveness of the individual ones. The effectiveness is evaluated in terms of color, turbidity and chemical oxygen demand (COD) reduction. The inﬂuence of operating parameters such as time of treatment, current density, and initial pH is also evaluated.
© 2012 Elsevier B.V. All rights reserved.
1. Introduction
Industrial efﬂuents are difﬁcult to treat using traditional biological systems due to the high variations in their compositions. Unlike municipal wastewater, industrial sources have higher organic load, color, and pH which ﬂuctuate [1,2]. While traditional biological reactors are very effective in digesting the organic matter in municipal wastewater into carbon dioxide and water, the effectiveness drops considerably when treating industrial wastewater. Biological reactors typically only reduce 50% of the biochemical oxygen demand (BOD5) and 35% of the chemical oxygen demand (COD) [3,4].