Fenton高级氧化技术去除水中有机污染物2-MIB的影响因素研究

针对目前比较关注的致嗅物质污染问题,选用Fenton高级氧化技术研究了其对水中致嗅物质2-甲基异莰醇（2-MIB）的去除,探讨了Fenton反应对水中致嗅物质的去除效能及H2O2/Fenton摩尔比、Fe2＋浓度、反应时间和溶液pH值各因素对氧化反应的影响。提出了Fenton氧化反应去除2-MIB的最佳反应条件。实验结果表明：Fenton高级氧化能有效去除水中的2-MIB。在H2O2/Fenton摩尔比为3.0、Fe2＋浓度10 mg/L、反应时间10 min和溶液pH值为3.0时,去除效率达到97.9%。Fenton氧化反应的操作条件（浓度、pH值等）比较容易实现,因此Fenton氧化技术在实际污染处理中有很大的应用前景。     

Treatment of biologically treated leachate by oxidation and coagulation

This work aims to investigate removal efficiency of oxidation and coagulation/flocculation processes, to provide an effective method for the treatment of biologically pre-treated leachate. Leachate containing 985 mg L(-1) COD was treated by using three treatment schemes, i.e. oxidation, coagulation/flocculation and the combined process of coagulation/flocculation followed by oxidation. The application of single oxidation resulted in the effective removal of COD and color up to 80.4 and 83.2%, respectively. However, residual COD values lower than 200 mg L(-1) could only be achieved under intensive experimental conditions (high dosage of Ca(ClO)(2) and prolonged oxidation time). Coagulation/flocculation yielded residual COD values higher than 200 mg L(-1) even at the optimum coagulation conditions. The combined treatment by coagulation/flocculation followed by oxidation yielded final COD lower than 100 mg L(-1) at the following conditions: pre-coagulation with 250 mg L(-1) PFS (poly-ferric sulfate) and over 30-min post-oxidation, or pre-coagulation with 300 mg L(-1) PFS and over 20-min post-oxidation. Hence, pre-coagulation with PFS followed by oxidation with Ca(ClO)(2) was recommended for advanced treatment of biologically treated leachate.     

Optimization of Fenton process for decoloration and COD removal in tobacco wastewater and toxicological evaluation of the effluent

Decoloration and chemical oxygen demand (COD) removal in tobacco wastewater by Fenton process has been optimized under 25 +/- 2 degrees C. The results showed that the optimal range of conditions were pH 4.13-4.66, Fe(2+) 0.29-0.34 g/L and H2O2 > or = 2.73 g/L. Within this range, up to 95% of colour and 90% of COD was removed. In an enlarged system, setting the optimal conditions as pH 4.50, Fe(2+) 0.34 g/L and H2O2 4.00 g/L, the colour removal rate was 96.03 +/- 2.57%, with COD removal rate of 93.30 +/- 2.92%. The residual COD of 73.67 +/- 19.70 mg/L in effluent had hit the State's first-class standard for the industrial discharge in China (< 100 mg/L COD, GB8978-1996). The ecological safety of Fenton process has also been evaluated. When reaction completed, the content of hydroxyl free radical (OH) was 3.26 +/- 0.44 mg/L. There was no inhibition of Fenton effluent in growth of Escherichia coli, Pseudomonas putida, Pseudomonas sp. HF-1, Acinetobacter sp. TW and Sphingomonas sp. TY. No oxidative stress was induced on strain HF-1 by Fenton effluent. Thus, Fenton process was one of high-efficiency and ecologically safe strategy for tobacco wastewater advanced treatment.     

Fenton试剂在微波条件下处理稻壳热解发电含酚废水的试验

采取试验手段,研究在微波条件下用Fenton试剂处理含酚废水的效果,探讨H2O2质量浓度、FeSO4质量浓度、pH值、反应时间和微波功率等因素对稻壳热解发电废水中COD、挥发酚及色度去除率的影响,并进行不同条件下Fenton反应的对比试验。结果表明,在微波条件下,Fenton试剂能快速降解含酚废水,处理后水样的COD去除率超过73%,挥发酚去除率超过99%,色度去除率接近50%。该含酚废水的最佳处理条件是:H2O2质量浓度为1500 mg/L,FeSO4质量浓度为100 mg/L,pH值为3,反应时间为10 min,微波功率为400 W。     

催化湿式氧化高浓度SDBS废水的研究

以过渡金属氧化物CuO为主活性组分,通过复合第二活性组分Co3O4和掺入电子助剂CeO2的考察,研制出适用于催化湿式氧化处理高浓度十二烷基苯磺酸钠(SDBS)废水的复合催化剂。实验结果表明,新制备的复合催化剂有较好的催化活性。通过对反应温度、氧气分压和废水pH值等工艺条件的考察,得出催化湿式氧化处理高浓度SDBS废水适宜的工艺条件为:反应温度为280℃、氧气分压为3 MPa、pH值为8.2,在此条件下用自制的催化剂处理初始COD质量浓度为4 942.1 mg/L的SDBS废水,在120 min内,COD去除率达到88.1%,而在相同条件下未加催化剂的湿式氧化COD去除率只有30.7%。     

Fenton试剂处理选矿废水的试验研究

研究用Fenton试剂处理含苯胺黑药(二苯胺基二硫代磷酸)模拟废水和实际选矿废水,分别考查了反应初始pH值、Fe2+浓度及H2O2用量对COD去除率的影响。结果表明:氧化时间为10 min,反应初始pH值为4,ρ(Fe2+)=1.83 g/L,ρ(H2O2)=5.55 g/L,模拟废水苯胺黑药的质量浓度为300 mg/L时,COD去除率达到83.6%;对于实际废水,当ρ(Fe2+)=50mg/L,pH值=3.5,ρ(H2O2)=1800mg/L时,出水ρ(COD)从1000mg/L降到32 mg/L,COD去除率为96.8%,达到废水排放标准,药剂成本估计为每处理1 m3废水需要费用18元。     

Multiple responses analysis and modeling of Fenton process for treatment of high strength landfill leachate

Landfill leachate is one of the most recalcitrant wastes for biotreatment and can be considered a potential source of contamination to surface and groundwater ecosystems. In the present study, Fenton oxidation was employed for degradation of stabilized landfill leachate. Response surface methodology was applied to analyze, model and optimize the process parameters, i.e. pH and reaction time as well as the initial concentrations of hydrogen peroxide and ferrous ion. Analysis of variance showed that good coefficients of determination were obtained (R2 > 0.99), thus ensuring satisfactory agreement of the second-order regression model with the experimental data. The results indicated that, pH and its quadratic effects were the main factors influencing Fenton oxidation. Furthermore, antagonistic effects between pH and other variables were observed. The optimum H2O2 concentration, Fe(II) concentration, pH and reaction time were 0.033 mol/L, 0.011 mol/L, 3 and 145 min, respectively, with 58.3% COD, 79.0% color and 82.1% iron removals.     

酸析—微电解—Fenton氧化预处理亚麻脱胶废水的研究

高浓度亚麻脱胶废水CODCr、色度都很高,不宜直接进行生物处理.试验采用酸析-微电解-Fenton氧化的预处理工艺,并对反应的影响因素进行了研究,试验结果表明,在pH=3,微电解90 min,H2O2投量1 500 mg/L,Fenton氧化120 min的条件下,CODCr去除率可以达到71.4%,色度去除率超过90%.同时该方法提高了废水的可生化性,有利于后续的生化处理.     

Fenton试剂处理港口化学品洗舱废水

根据珠海某港口化学品洗舱废水的组成,配置甲醛、甲苯、苯酚的单独污染物模拟废水,采用Fenton试剂对港口废水和模拟废水进行氧化处理。通过实验探讨了不同的H2O2和Fe2+浓度、pH值、反应时间下各种废水COD的去除情况,确定了各种废水最佳的操作条件。港口废水在最佳的操作条件下COD去除率约为88%,废水的COD质量浓度从2 000~2 200 mg/L降到低于280 mg/L,废水由原来的无法生化变为易生物降解。苯酚、甲醛、甲苯模拟废水在各自最佳的操作条件下,COD去除率也都达到85%以上。     

Effective degradation of para-chloronitrobenzene through a sequential treatment using zero-valent iron reduction and Fenton oxidation

In this study, zero-valent iron (ZVI) was used to pretreat para-chloronitrobenzene (p-CNB), and the major product was para-chloroaniline (p-CAN). By adding H(2)O(2) directly, further p-CAN degradation can be attributed to Fenton oxidation because ferrous ions (Fe(2+)) released during the ZVI corrosion could be used as an activator for H(2)O(2) decomposition. In the reduction process, the reduction efficiency of p-CNB as well as Fe(2+) concentration increased with increasing iron dosage and decreasing solution pH. Under the optimal conditions, 25 mg L(-1) of p-CNB could be transformed in 3 h when initial solution pH was 3.0 and ZVI dosage was 2.0 g L(-1). A sufficient amount of Fe(2+) (50.4 mg L(-1)) was obtained after the above reaction to activate H(2)O(2). In the Fenton process, the oxidization of p-CAN was also more effective in acidic conditions and it increased with increasing H(2)O(2) concentration. The control experiments showed that the sequential treatment was more effective than Fenton oxidation alone in treating p-CNB wastewater since the removal rate of total organic carbon (TOC) was improved by about 34%. It suggested that the amino function group is more susceptible to oxidative radical attack than the nitro function group. Therefore, sequential treatment using zero-valent iron reduction followed by Fenton oxidation is a promising method for p-CNB degradation.     

高浓度焦化废水的预氧化-混凝处理研究

焦化废水成分十分复杂,污染物浓度高,性质非常稳定且水量大,是典型的难降解有机废水。使用H2O2为氧化剂,FeSO4.7H2O为催化剂的Fenton氧化法对钢铁焦化厂废水的终冷水进行了试验研究,氧化处理后用FeCl3为混凝剂对COD,NH3-N,色度及浊度的去除率进行了系统的考查。确定了氧化反应的影响因素和最佳的混凝实验条件。结果表明:当pH值控制在3左右,反应时间为30 min,反应温度为80℃,焦化废水的COD,NH3-N,浊度和色度去除率分别达到了93.1%,96.2%,90.8%和90.2%。     

湿式氧化技术处理化工废水的研究

采用湿式氧化技术处理在生产磺胺间二甲氧嘧啶过程中产生的高浓度有机废水。在反应温度为250℃,初始ρ(COD)为4 575 mg/L,反应时间为2 h,pH值为7~8时,采用湿式双氧水氧化和催化湿式氧化,COD去除率分别为78.3%和92.0%,表明催化湿式氧化具有较好的COD去除效果。同时考察了催化湿式氧化中反应温度、反应时间、废水pH值对COD去除率的影响。     

电解Fenton法处理线路板生产废水中有机物质

研究了Fenton法对线路板生产废水中有机物质的处理效果,比较传统Fenton法和电解Fenton法处理效果。在同样反应时间里,电解Fenton法的COD平均去除率为55.7%,H2O2的最大投加量为3.75 g/L,而传统Fenton法的COD平均去除率为23.7%,H2O2的投加量为5.45 g/L。确定了电解Fenton法小试装置处理线路板废水的最佳处理条件。     

Fenton and photo-Fenton treatment of a synthetic tannin used in leather tannery: a multi-approach study.

The aim of this work was to compare the behaviour of Fenton and photo-Fenton (UV-A, UV-C) processes to treat synthetic tannin (syntan) used in leather tannery which is one of the most polluting industries, releasing many xenobiotics. Both oxidation processes were performed at pH 3.0 and temperature 40-45 degrees C, which is the original temperature of the re-tanning process, in synthetic solutions containing 100 and 300 mg/L of COD equivalent of syntan. The efficiency of the applied oxidation processes was monitored by chemical oxygen demand (COD), oxidation redox potential (ORP) and aromaticity (UV280) and double bond (UV254) absorbance measurements. Acute toxicity test on Daphnia magna was performed to monitor toxicity in untreated and treated syntan solution. Gas chromatography-mass spectrometry (GC-MS) was applied to identify by-products of partial oxidation occurring in treated samples. The effective ratio of H2O2/FeSO4 for photo-Fenton processes was found to be feasible in terms of reagents used in the process.     

Effects and mechanism of ozonation for degradation of sodium acetate in aqueous solution

The degradation efficiencies and mechanism of ozonation for the degradation of sodium acetate in aqueous solution were investigated under atmospheric pressure at room temperature (293 K). The effects of the initial pH value, reaction time, and concentrations of HCO3-, CO32-, CaCl2, and Ca(OH)2 on the removal rate of chemical oxygen demand (COD) were studied. The results indicated that ozonation obviously improved the degradation rate of sodium acetate when the pH value of the solution was not less than 8.5. A suitable long reaction time may be helpful in increasing the COD removal rate, and a removal rate of 36.36% can be obtained after a 30-minute treatment. The COD removal rate increased firstly and decreased subsequently with the increase of the HCO3- concentration (from 0 to 200 mg/L), and under the same experimental condition it reached the optimum 34.66% at the HCO3- concentration of 100 mg/L. The COD removal rate was 5.26% lower when the concentration of was 200 mg/L than when there was no HCO3-. The COD removal rate decreased by 15.68% when the CO32- concentration increased from 0 to CO32- 200 mg/L. has a more obvious scavenging effect in inhibiting the formation of hydroxyl radicals than HCO3-. CaCl2 and Ca(OH)2 could increase the degradation efficiency of sodium acetate greatly, and the COD removal rates reached 65.73% and 83.46%, respectively, after a 30-minute treatment, 29.37% and 47.10% higher, respectively, than with single ozone oxidation. It was proved that the degradation of sodium acetate in the ozonation process followed the mechanism of oxidization with hydroxyl free radicals (·OH).     

光催化氧化降解活性艳红X-3B模拟染料废水试验

研究Fenton氧化技术处理偶氮染料活性艳红X-3B模拟废水的反应条件及处理效果,主要考察了Fe2+和H2O2的用量、温度以及废水的pH值等条件对色度和化学耗氧量(COD)去除率的影响。实验结果显示,Fenton氧化反应对废水色度和COD都有较好的去除效果,去除率分别为99.78%和94.34%。考察了不同光照条件Fenton试剂对废水的处理效果,结果表明光照能够加快Fenton反应速度、提高COD去除率。     

微电解-Fenton联合工艺处理拉米夫定废水的试验研究

研究了铁炭微电解-Fenton联合工艺对高浓度难生化处理的拉米夫定制药废水的预处理效果.结果表明:在微电解2 h, Fenton 1 h,pH为3,H_2O_2(30%)投量5 mL/L条件下,COD_(Cr)去除率可以达到76%,色度去除率超过98%,BOD/COD由0.15提高到0.52,有利于后续的生化处理.     

Photocatalytic removal of cyanide with illuminated TiO(2)

Effects of TiO(2) dosage, pH and initial cyanide concentration on the removal efficiency of cyanide from aqueous solutions with illuminated TiO(2) have been investigated. Adsorption and oxidation were recognized as significant processes for the elimination of cyanide. From the Langmuir isotherm, the maximum adsorption capacity was determined as 17.24 mg/g at pH 7. Adsorbed amount of cyanide slightly increased as the TiO(2) dosage increased. However, as no significant increase was observed above 1 g/L TiO(2), an optimum TiO(2) dosage was determined as 1 g/L. Photocatalytic oxidation efficiency of cyanide was greatly affected by the solution pH. It increased as the solution pH decreased. The photocatalytic oxidation efficiency after 120 min was 80.4% at pH 3 while it was only 20.4% at pH 11. Photocatalytic oxidation of cyanide was well described by the second-order kinetics. Photocatalytic reaction with illuminated TiO(2) can be effectively applied to treat industrial wastewater contaminated with cyanide.     

Comparison of AOPs for the removal of natural organic matter: performance and economic assessment.

Control of disinfection by-products during water treatment is primarily achieved by reducing the levels of organic precursor species prior to chlorination. Many waters contain natural organic matter at levels up to 15 mg L(-1); therefore it is necessary to have a range of control methods to support conventional coagulation. Advanced oxidation processes are such processes and in this paper the Fenton and photo-Fenton processes along with photocatalysis are assessed for their NOM removal potential. The performance of each process is shown to be dependent on pH and chemical dose as well as the initial NOM concentration. Under optimum conditions the processes achieved greater than 90% removal of DOC and UV254 absorbance. This removal led to the THMFP of the source water being reduced from 140 to below 10 microg L(-1), well below UK and US standards. An economic assessment of the processes revealed that currently such processes are not economic. With advances in technology and tightening of water quality standards these processes should become economically feasible options.     

催化铁/混凝法预处理酸性化工废水pH变化规律及混凝最佳工况研究

pH值是催化铁法预处理酸性化工废水主要考察指标,是Fe2+产生量和混凝效果的控制因素,为此进行了催化铁预处理化工废水pH值变化和Fe2+产生规律及后继混凝效果的研究。结果表明:催化铁反应最适初始pH为2.75,反应时间为1 h;混凝反应最佳条件为:Fe2+浓度为120 mg/L,pH控制在8.0～8.5;系统COD去除率为56.8%,色度去除率为92%;催化铁处理后的化工废水与印染废水混合进行混凝反应的最适宜pH为8.0～8.5。