UV/Fenton/均相铜类Fenton氧化处理紫菜加工废水COD及色度研究

以COD和色度作为评价指标,采用均相Fenton、Cu-Fenton、UV/Fenton、UV/Cu-Fenton体系处理紫菜加工废水,探究了在室温条件下不同初始pH值、Fe^(2+)和Cu^(2+)投加量、H_(2)O_(2)投加量等因素对出水COD和色度的去除效果,通过正交试验确定了最佳反应条件,同时对反应机理进行了分析。分析显示羟基自由基(·OH)是UV/Fenton/均相铜类Fenton体系去除紫菜废水中COD及色度的主要活性基团。在最佳反应条件下,UV/Fenton体系在100 min时出水COD为40 mg/L,色度为25,比无UV时最佳反应时间缩短了50 min;UV/Cu-Fenton体系,在60 min时出水COD为35 mg/L,色度为20,比无UV时最佳反应时间缩短了一半,UV/Fenton体系和UV/Cu-Fenton体系出水COD及色度均能达标排放。

Heterogeneous UV／Fenton catalytic degradation of wastewater containing phenol with Fe－Cu－Mn－Y catalyst

The heterogeneous UV/Fenton process with the appropriate amount of Fe-Mn-Cu-Y as catalyst was developed and various operation conditions for the degradation of phenol were evaluated. The results indicated that by using the het-erogeneous UV/Fenton process, the CODcr removal rate reached almost 100% for wastewater containing phenol. Compared with the homogeneous process, the developed catalyst could be used at wider pH range in the UV/Fenton process. Com-parison of various heterogeneous process showed that heterogeneous UV/Fenton process was best. The heterogeneous UV/Fenton process with Fe-Mn-Cu-Y catalyst is highly efficient in degrading various organic pollutants.

β-FeOOH/SiO_(2)复合非均相Fenton催化剂制备及对甲基橙溶液的降解

采用简单、环保的方法合成β-FeOOH/SiO_(2)复合非均相Fenton催化剂,采用红外光谱仪(FT-IR)、X射线衍射仪(XRD)、X射线光电子能谱仪(XPS)、透射电子显微镜(TEM)对催化剂进行表征分析,考察质量比、合成温度和合成时间对催化剂催化活性的影响,通过分析催化剂类型、用量及双氧水用量,探究β-FeOOH/SiO_(2)复合催化剂处理染料废水的最佳工艺条件。结果表明:β-FeOOH/SiO_(2)复合催化剂制备工艺简单,操作条件温和,易于工业化生产;β-FeOOH/SiO_(2)复合催化剂在满足m(β-FeOOH)/m(SiO_(2))=1∶1,反应温度为90℃,反应时间为8 h时,具有最佳的催化活性;在30℃条件下,β-FeOOH/SiO_(2)的加入量为5 g/L,过氧化氢的加入量为0.1 L/L时,200 mg/L甲基橙染料废水的去除率最大,达到98.85%,对亚甲基蓝和罗丹明B的去除率分别达到90.44%和99.25%;β-FeOOH/SiO_(2)复合催化剂对染料废水具有良好的降解效果。

高炉渣非均相类Fenton降解亚甲基蓝废水

本文以高炉渣为催化剂,通过非均相类Fenton的方法降解模拟亚甲基蓝废水,在有无光照的条件下,考察了高炉渣用量、H_(2)O_(2)用量、pH、反应时间等因素对模拟废水的色度及COD去除率的影响。实验证明:有光照条件下的去除效果均优于无光照,光照条件下该体系最佳条件为:pH=3,高炉渣用量为0.1 g/100 mL,H_(2)O_(2)(质量分数30%)为0.2 mL/100 mL,反应时间2 h,亚甲基蓝废水脱色率及COD去除率均达到100%。动力学研究表明:有光照条件下反应速率大于无光照条件,二者反应都更符合二级动力学模型。

Iron-glutamate-silicotungstate ternary complex as highly active heterogeneous Fenton-like catalyst for 4-chlorophenol degradation

A novel iron-glutamate-silicotungstate ternary complex（FeШGluS iW） was synthesized from ferric chloride（FeI II）,glutamic acid（Glu）,and silicotungstic acid（SiW）,and used as a heterogeneous Fenton-like catalyst for 4-chlorophenol（4-CP） degradation at neutral pH value. The prepared FeШGluS iW was characterized using inductively coupled plasma atomic emission spectroscopy,thermogravimetry,Fourier-transform infrared spectroscopy,ultraviolet-visible diffuse reflectance spectroscopy,X-ray diffraction,and field-emission scanning electron microscopy. The results showed that FeШGluS iW has the formula [Fe（C5H8NO4）（H2O）]2SiW 12O40？13H2O,with glutamate moiety and Keggin-structured SiW 12O404- heteropolyanion. The catalyst showed high catalytic activity in 4-CP degradation in the dark and under irradiation. Under the conditions of 4-CP 100 mg/L,FeШGluS iW 1.0 g/L,H2O2 20 mmol/L,and pH = 6.5,4-CP was completely decomposed in 40 min in the dark and in 15 min under irradiation. When the reaction time was prolonged to 2 h,the corresponding total organic carbon removals under dark and irradiated conditions were ca. 27% and 72%,respectively. The high catalytic activity of FeI IIGluS iW is resulted from hydrogen bonding of H2O2 on the FeI IIGluS iW surface. The enhanced degradation of 4-CP under irradiation arises from simultaneous oxidation of 4-CP through Fenton-like and photocatalytic processes respectively catalyzed by ferric iron and the SiW 12O404- hetropolyanion in FeШGluS iW.

UV/Fenton法深度处理含双氯芬酸和锌废水的工艺优化

为研究含药物和重金属复合废水的处理方法,采用UV/Fenton工艺对经过生物处理后的含双氯芬酸(DCF)和Zn^(2+)废水进行处理,通过单因素实验法分析了H_(2)O_(2)浓度、Fe^(2+)浓度和反应时间对废水中COD、DCF和NH_(4)^(+)-N去除效果的影响。结果表明,随着H_(2)O_(2)浓度和Fe^(2+)浓度投加量的升高,COD和DCF的去除率呈先上升后下降的趋势,NH_(4)^(+)-N的去除率则趋于稳定。随着反应时间的增加,COD、DCF和NH_(4)^(+)-N除率均为先上升后趋于平衡。结合成本和效率考虑,得出最佳处理条件为:H_(2)O_(2)的最佳投加量为600 mg/L,Fe^(2+)的最佳投加量为45 mg/L,最佳反应时间应设置为90 min。

紫外光引发Fenton氧化技术协同去除造纸中段废水COD_(Cr)的性能研究

对紫外光引发Fenton氧化技术协同处理造纸中段废水COD_(Cr)进行了研究,探究反应时间、FeSO_(4)·7H_(2)O浓度、H_(2)O_(2)浓度、pH值、紫外光强度等因素对COD_(Cr)去除效率的影响。实验结果表明,在反应时间80min,FeSO_(4)·7H_(2)O浓度0.6 mol/L,H_(2)O_(2)浓度0.3 mol/L,pH值为4,以及紫外光强度为14 mW/cm^(2)的最优条件下,该技术能够实现造纸中段废水74%的COD_(Cr)去除率。紫外光引发Fenton氧化技术能够有效促进Fenton氧化反应中·OH自由基的生成,提高造纸中段废水的COD_(Cr)去除效率。

Photochemically enhanced degradation of phenol using heterogeneous Fenton-type catalysts

The degradation of phenol was carried out using heterogeneous Fenton-type catalysts in the presence of H_2O_2 and UV. Catalysts were prepared by exchanging and immobilizing Fe 2+ in zeolite 13X, silica gel or Al_2O_3. The concentration of phenol solution was 100 mg/L. The amount of H_2O_2 added was the stoichiometric amount of H_2O_2 required for the total oxidation of phenol. Under the irradiation of medium pressure light (300 W) phenol was mineralized within 1 h in the presence of Fe 2+/zeolite 13X. The COD removal rate was enhanced in the presence of Fe 2+/zeolite 13X compared to that of Fe 2+/silica gel or Fe 2+/Al_2O_3. Analogous homogenous photo-Fenton reaction with equivalent Fe 2+ was also carried out to evaluate the catalysis efficiency of Fe 2+/zeolite 13X. Results showed that the COD removal rate was near to that of homogeneous Fenton, while heterogeneous Fe 2+/zeolite 13X catalyst could be recycled.

UV-Fenton工艺的研究进展及其在水环境微污染处理领域的应用

近年来,水环境中的新型难降解污染物受到广泛关注,催生了该领域大量降解、还原及吸附等处理技术的相关研究,尤其是基于强氧化性自由基的高级氧化法(AOPs),典型工艺就是Fenton法。但在传统Fenton氧化体系中,H_(2)O_(2)的利用效率较低,铁泥产量高,且pH限制范围较窄,影响了Fenton反应的整体降解效果及应用。因此,引入了紫外光以提高H_(2)O_(2)的分解效率,即UV-Fenton体系,较传统Fenton可以有效减少Fe^(2+)用量,促进Fe^(3+)向Fe^(2+)的转化,加速H_(2)O_(2)分解,并提高H_(2)O_(2)利用率,进而使有机物矿化更彻底。文章详细对比了传统Fenton与UV-Fenton工艺,介绍UV-Fenton工艺的反应原理,并讨论其影响因素(例如光照强度、Fe^(2+)和H_(2)O_(2)用量等),同时,文章总结了UV-Fenton工艺在水环境领域及微污染处理中的实际应用,包括有机染料、抗生素、农药及全氟化合物等。最后对UV-Fenton工艺的研究改进方向以及实际应用存在问题提出了展望。

Fe–Mn/MCM-41: Preparation,Characterization,and Catalytic Activity for Methyl Orange in the Process of Heterogeneous Fenton Reaction

Active Fe-and Mn-loaded MCM-41(Fe–Mn/MCM-41),which was synthesized via a hydrothermal reaction followed by impregnation,is used in the heterogeneous Fenton reaction to degrade methyl orange(MO) in aqueous solution. The synthesized samples were characterized by X-ray diffraction,scanning electron microscopy,transmission electron microscopy,N_2 adsorption–desorption isotherm analysis,Fourier transform infrared spectroscopy,and X-ray photoelectron spectroscopy. Compared with Fe/MCM-41 and Mn/MCM-41,Fe–Mn/MCM-41 showed higher activity for MO degradation and mineralization. Effects of various operating parameters,such as pH,Mn content,and H_2O_2 dosage,on the degradation process were subsequently investigated. Results of experiments on the effect of radical scavengers revealed that the degradation of MO could be attributed to oxidation by HO_·. The synergy of Fe and Mn species in the Fenton oxidation process was also explained.

蒙脱土在光助非均相Fenton 反应中的应用研究进展

蒙脱土因具有良好的阳离子交换能力和吸附能力被广泛用作非均相Fenton催化剂的载体。介绍了蒙脱土负载铁氧化物、蒙脱土负载改性铁氧化物和蒙脱土负载半导体/铁氧化物三类催化剂在非均相光-Fenton反应处理水中污染物的应用,就三类催化剂对污染物的降解机理和蒙脱土的作用进行分析,并对蒙脱土基非均相Fenton催化剂未来的研究方向进行探讨。

Membrane enhanced COD degradation of pulp wastewater using Cu_2O/H_2O_2 heterogeneous Fenton process

Both activity and stability of the catalyst can be improved in heterogeneous Fenton reaction,in particular,with no limitation for the working p H and no production of the sludge.In this work,a combination of catalyst Cu_2O and pore-channel-dispersed H_2O_2is proposed to treat the pulp wastewater.Degradation degree of CODs in the wastewater was up to 77%in the ceramic membrane reactor using Cu_2O powder(2.0 g·L^(-1))and membranefeeding H_2O_2(0.8 ml·L^(-1))within 60 min.Evolution of·OH radical formation in the advanced oxidation process was analyzed with a fluorescent method.Utilization efficiency of H_2O_2was successfully enhanced by 10%with the membrane distributor.Further on,the catalyst recyclability was evaluated in a five-cycle test.The concentration of copper ions being dissolved in the treated water was monitored with ICP.After Cu_2O/H_2O_2(membrane)treatment the effluent is qualified to discharge with COD concentration lower than 15 mg·L^(-1)with regard to the national standard GB25467-2010.

Performance Evaluation of Modified Black Clay as a Heterogeneous Fenton Catalyst on Decolorization of Azure B Dye: Kinetic Study and Cost Evaluation

Black clay (BC) was used as a catalyst for the decolorization of Azure B dye by Fenton process. BC was modi ed by acid, alkali, distilled water, and calcination to check their changes in characterization and e ciency on decolorization of Azure B. Among three modi ed catalysts, maximum decolorization was obtained by acid-modi ed BC (AMBC) catalyst due to the highest removal of impurities, comparatively. The characterization of AMBC was done by Fourier-transform infrared spectroscopy and X-ray di raction spectroscopy which show the presence of metal ion. The BET surface area, pore volume, pore size, and density of AMBC were calculated to be 79.402 m 2 /g, 0.0608 m 3 /g, 0.00306 nm, and 16 g/cm 3 , respectively. The highest decolorization of 97.59% was achieved only in 10 min using AMBC at optimized calcination of 100 °C and 3 h of aging. AMBC was considered as the main catalyst for optimizing the di erent process parameters. Optimized conditions were obtained: pH 2, 0.2 mL of H 2 O 2 , catalyst dose 0.3 g, room temperature (30 °C), and stirring speed 400 r/min. The catalyst has showed excellent stability and reusability. It could remove more than 85% of color even after four cycles of run and less than negligible leaching of iron. AMBC has good recycling ability among other modi ed catalysts. To check the selectivity of catalyst, di erent dyes such as Congo red and mixed dye (mixture of Azure B and Congo red) decolorization were studied. In the present work, kinetic study was also carried out and a three-stage decolorization process was found.

凹凸棒负载碳-铁复合材料的制备及非均相Fenton反应降解水中亚甲基蓝的研究

以凹凸棒为载体,采用共沉淀法和热解法制备了新型凹凸棒负载碳-铁复合材料。通过X射线衍射仪、傅里叶变换红外光谱仪、冷场发射扫描电子显微镜、X射线光电子能谱仪、热重分析仪对复合材料进行表征,用亚甲基蓝水溶液模拟有机染料废水,考察复合材料在光暗体系下非均相Fenton催化降解亚甲基蓝的性能。结果表明,光照和暗环境下,最佳pH分别为4.0、3.5,反应120min时脱色率分别可达99.6%和96.3%。复合材料在光照环境下具有更好的催化活性,循环5次后,亚甲基蓝的脱色率仍可达99%,总有机碳去除率为42.2%,表现出良好的重复使用性。

Leachate Treatment by Heterogeneous Fenton on an Activated Carbon Substrate with Fe(II) Impregnated

Organic components contained in leachates resulting from decomposition of waste are difficult to degrade. They also contain inorganic components, as nitrogen compounds, phosphates, and chlorides, also Ca, Mg, K, and heavy metals. Leachate volume and its composition vary depending on biogeochemistry of type site of deposited residues, and age of sanitary landfill. In this study, it conducted a Heterogeneous Fenton, advanced oxidation process using lignitic activated carbon as solid matrix, with and without Fe2+ impregnation, for the treatment of leachate (Le) obtained from a sanitary landfill located in the city of Mérida, Yucatan, Mexico. In this study was determined the efficiency of Heterogeneous Fenton process for to remove Chemical Oxygen Demand (COD) and Color from crude leachates using mesoporous activated carbon, previously treated with HCl, HNO3, and a mixture of both acids and impregnated with Fe2+ on actived carbon. It was studied of activated carbon behavior previously treated with each acid and the mixture, washed with hot water and impregnated with Fe2+ using FeCl2.4H2O and FeSO4·7H2O salts. For leachate treatment by Heterogeneous Fenton reaction, it was selected carbon pretreatment with HCl acid and impregnation with FeSO4·7H2O. Treatment with HCl presented the advantage of not prematurely oxidize to Fe2+. In order to select an optimal dose and achieve an adequate concentration of HO· radicals dosage tests was carried out H2O2. By selecting the indicated procedure, it was obtained more than 80% performance in removing COD and Color from crude leachate. The confidence level for the selected variables (acids and impregnation) was determined by a statistical analyzes using the Centurion XVII software. Finally, mesoporous lignitic carbon used in this study was found to be adequate for this oxidation process, and this method presented the advantage of not producing sludge as in traditional Fenton reaction.

Catalytic oxidation degradation of phenol in wastewater by heterogeneous Fenton reagent

Heterogeneous Fenton reagent, as a strong oxidizer, has been used widely in the treatment ofwastewater. We prepared Fe2O3/γ-Al2O3 catalyst by impregnation method and characterized it by powder X-ray diffraction （XRD） and X-ray photoelectron spectroscopy （XPS）, scanning electron microscopy （SEM）. Test results show that Fe203 crystal was compounded on the γ-Al2O3 carder. We tested and optimized Fe203/γ-Al2O3 /H2O2 and Fe2O3/γ-Al2O3 /H2O2/UV processes to remediate organic material of phenol, using phenol solution with an in. itial concentration of 250 mg/L as a representative of phenolic industrial Wastewater. The preparation conditions were optimized based on performance of Fe2Oa/γ-Al2O3 catalyst and the processes to degrade phenol in aqueous environments. The experimental results showed that the phenol removal perfomance with Fe2O3/γ-Al2O3 /H2O2/UV was more complete than with Fe2O3/γ-Al2O3 /H2O2 and degradation rate of phenol reached 89.4% and 94.7% respectively after reaction for2 h.

UV-Fenton法对四氢呋喃废水预处理及出水影响分析

基于制药园区需要针对不同制药废水选取合适的预处理技术的实际工程问题,以及完善预处理研究中对出水分析不足的问题,以成分为1 g·L^(-1)甲醇、1 g·L^(-1)四氢呋喃(THF)的制药废水为研究对象,筛选出具有持续氧化能力的UV-Fenton法针对THF废水进行预处理。随后通过单因素实验得出最优工艺条件:H_(2)O_(2)投加量为0.0938 mol·L^(-1)、pH=2和n(H_(2)O_(2))∶n(Fe^(2+))=10∶1。该条件下THF废水COD去除率达到86.39%,B/C值达0.40,证实该技术能够有效处理该废水。同时进一步探究UV-Fenton法对甲醇-THF废水处理效果,发现将试剂投加量增至3倍时对甲醇-THF废水COD去除率达到94.03%,B/C值达0.71,证明该体系对甲醇-THF废水同样有效。最后,通过GC-MS、HPLC、T.E.S.T毒性分析以及B/C值测定对THF废水预处理出水水质进行分析,结果表明出水中有机物的可生化性得到改善,但是由于草酸和乙酸等有机酸的生成导致出水pH呈现酸性,其会影响后续生化处理,因此建议采用中和法解决出水呈现酸性的问题,为后续生化处理提供有利条件。

酸性红R在UV-类Fenton体系中的光降解实验

本论文选用了偶氮染料ARR为主要研究对象,研究它在UV-类Fenton体系中的光催化降解行为。采用紫外杀菌灯(λ≥254 nm)为光源,光化学反应实验在自制的光催化反应装置中进行。光照反应时间50 min,间隔相同时间取样,采用分光光度法检测ARR在光催化降解过程中的浓度变化,系统地研究了ARR的初始浓度、反应体系pH值、蒙脱土/H_(2)O_(2)配比、以及NO_(3)^(-)、EDTA、Cl^(-)、丙酮酸钠等对偶氮染料ARR光催化降解的影响。结果表明:在pH=3.0、66 mg/L的30%H_(2)O_(2)和浓度为1 g/L的蒙脱土条件下,ARR在UV-类Fenton体系可以获得较高的反应速率,NO_(3)-、丙酮酸钠对ARR的光催化降解有促进作用,而Cl^(-)、EDTA对ARR的光催化降解有抑制作用。

Synthesis of Magnetically Modified Fe-Al Pillared Bentonite and Heterogeneous Fenton-like Degradation of Orange II

Magnetically modified Fe-Al pillared bentonite（Fe3O4/ Fe-Al-Bent） was prepared via chemical co-precipitation method and characterized by powder X-ray diffraction（XRD）, Brunauer-EmmettTeller（BET）, Fourier transform infrared spectroscopy（FTIR） and scanning electron microscopy（SEM）. A series of experiments were carried out to investigate the degradation of Orange II by the obtained heterogeneous catalysts in the presence of H2O2. The experimental result indicated that the synthetic materials had a high catalytic activity and good reusability.

Using Goethite as a Heterogeneous Fenton Catalyst for The Removal of Tetracycline Hydrochloride: Effects of Its Adsorptive and Reductive Activities

The removal of the antibiotic compound tetracycline hydrochloride (TC) was investigated by using goethite/H2O2 as a heterogeneous Fenton reagent. Five principle operational parameters, especially solution pH value, were taken into account to investigate how the heterogeneous Fenton process factors mediated the TC removal. This process was effective but seriously impacted by the pH value and temperature, as well as the dosages of α-FeOOH, TC and H2O2. Very interestingly, the acidic and alkaline aqueous medium conditions were both very favorable due to the occurrence of transformation of Fe(III) to Fe(II) on goethite surfaces reduced by TC at pH 3.0~4.0 even though with a low adsorption capacity of TC because its maximum adsorption of negatively charged form occurred at pH around 8.0[1], thereby greatly promoting the TC Fenton oxidative elimination. However, a rapid initial TC decay was observed at the first 5 min, followed by a much slower retardation stage, which was likely because the reductive transformation of Fe(III) to Fe(II) by TC in the solution was inhibited as the Fenton reaction proceeded. Moreover, the hydroxyl radical scavenger t-butanol addition can decrease the removal rate of TC in the goethite/H2O2 system to a certain extent. This further indicated that the main reactive species in this process were hydroxyl radicals[2]. All the goethite-catalysed heterogeneous Fenton reactions are responsible for the TC removal following the Langmuir-Hinshelwood model, were well fitted to pseudo-first order kinetics (R2】0.99), and their apparent activation energy (E) for this Fenton-like reaction was 31.86 kJ mol 1, a low value that is highly consistent with the ease of TC decay greatly enhanced by the temperature rise, indicated that the interfacial controlling interactions such as a proton induced solubilization and a reductive dissolution of goethite can clearly improve its Fenton catalytic activity[3], and these dissolution processes may not be effective in some cases, while the TC adsorption process may always play an important role to control the TC removal rate during the Fenton reaction.