Oxidation of Partially Hydrolyzed Polyacrylamide from Polymer Flooding Processes Using Fenton Reagents

The degradation of partially hydrolyzed polyacrylamide(HPAM) found in alkaline/surfactant/polymer flooding sewage was investigated using Fenton-type reagents. Different Fenton reagent treatments for HPAM degradation were compared. The effects of pH, hydrogen peroxide(H_(2)O_(2)), ferrous ion(Fe^(2+)), and tartaric ion(C_(4)H_(4)O_(6)^(2-)) concentrations were studied. The degradation reaction occurred within a wide range of pH(3–9). The HPAM degradation performance of photo-Fenton processes using solar light and UV were compared with that of the Fenton process. The degradation rate was found to be strongly dependent on the H_(2)O_(2)/Fe^(2+)/C_(4)H_(4)O_(6)^(2-)molar ratio. The HPAM degradation efficiency was 90%, and the chemical oxygen demand removal efficiency was 85%. HPAM could be degraded into a compound with a lower molecular weight, but it was difficult to achieve complete mineralization to CO_(2). The presence of intermediate products hindered further oxidation in the Fenton process.

Degradation of Silicone Rubbers in Fenton's Reagents

Gaskets are applied in PEMFCs（proton exchange membrane fuel cells） to keep reactant gases and liquid within their respective regions, which are of great significance for the both sealing and electrochemical performance of fuel cells during the long-term operation. In this study, the degradation of silicone rubbers, often selected as seals in PEMFCs, in Fenton＇s reagents with different H_2O_2 concentrations was investigated. The changes in chemical properties, mechanical behavior and surface morphology of the samples were studied before and after exposure to the test environment over time. It is found that increasing H_2O_2 concentration will degrade the rubbers more severely. The experimental results elucidate the degradation mechanism of silicone rubbers in Fenton＇s reagents and the influence of H_2O_2 in the degradation process.

Exploitation of Fenton and Fenton-like reagents as alternative conditioners for alum sludge conditioning

The use of Fenton＇s reagent （Fe^2＋/H2O2） and Fenton-like reagents containing transition metals of Cu（Ⅱ）, Zn（Ⅱ）, Co（Ⅱ）, and Mn（Ⅱ） for an alum sludge conditioning to improve its dewaterability was investigated. The results obtained were compared with those obtained from conditioning the same alum sludge using cationic and anionic polymers. Experimental results show that Fenton＇s reagent was the best among the Fenton and Fenton-like reagents for the alum sludge conditioning. A considerable effectiveness of capillary suction time （CST） reduction efficiency of 47% can be achieved under test conditions of Fe^2＋/H2O2 = 20/125 mg/g DS （dry solid） and pH 6.0. The observation of floc-like particles after Fenton＇s reagent conditioning of alum sludge suggested that the mechanism of Fenton＇s reagent conditioning was different from that of polymer conditioning. In spite of the lower efficiency in the CST reduction of Fenton＇s reagent in alum sludge conditioning compared to that of polymer conditioning, Fenton＇s reagent offers a more environmentally safe option. Tiffs study provided an example of proactive treatment engineering, which is aimed at seeking a safe alternative to the use of polymers in sludge conditioning towards achieving a more sustainable sludge management strategy.

芬顿试剂(Fenton's reagent法降解对苯二酚和工业废水

可溶性亚铁盐和H2O2的组合称为芬顿试剂(Fenton’s reagent),是一种氧化能力很强的氧化剂,常用于废水的净化处理。本文以对苯二酚为代表物,探讨用Fenton试剂氧化的反应条件,并用最佳的实验条件处理工业废水,90分钟工业废水的COD去除率可达71.6％。

Degradation of polyvinyl-alcohol wastewater by Fenton’s reagent: Condition optimization and enhanced biodegradability

The pretreatment of refractory polyvinyl-alcohol （PVA） wastewater with low value of CODcr by Fenton＇s reagent was investigated to enhance the biodegradabilily. The effects of operating conditions such as pH of the solution, Fe2＋ dosage, H2O2 dosage, reaction time and initial PVA concentration on the removal efficiency of CODCr were discussed. It is demonstrated that the optimum value of pH for removal of CODcr is 5 and the most suitable dosages of H2O2 （2%） and FeSO4 （10 mg/L） are 5% and 8.0%, respectively. When the initial CODcr value of the PVA water is 760 mg/L, the favorable reaction time is 110 min. Under these optimum conditions, the removal ratio of CODcr is 58.6% 61.4%, and the value of biodegradability （CODB/CODcr） increases markedly from 8.9% 9.7% to 62.6% 68.3%.

Degradation of 4-Chlorophenol Solution by Synergetic Effect of Dual-frequency Ultrasound with Fenton Reagent

4-Chlorophenol (4-CP) solution was treated by dual-frequency ultrasound inconjunction with Fenton reagent, and obvious improvement in the 4-CP degradation rate was observedin this advanced oxidation process. Experimental results showed that ultrasonic intensity,saturating gas and pH value affected greatly the 4-CP removal rate. Among four different saturatinggases (Ar, O_2, air and N_2), 4-CP degradation with Ar-saturated solution was the best. However, inthe view of practical wastewater treatment, using oxygen as the saturating gas would be moreeconomical. The addition of Fenton reagent followed the first-order kinetics and increased the 4-CPdegradation rate. The 4-CP removal rate increased by around 126% within 15 min treatment. Thesynergetic effect of dual-frequency ultrasound with Fenton reagent on 4-CP degradation was obviouslyobserved.

Treatment of Wastewater Containing RDX by Fenton's Reagent

Fenton's reagent was employed to treat the wastewater containing RDX.The effects of FeSO4 concentration,H2O2 concentration,pH value,reaction time,temperature and initial COD of wastewater on residual COD of wastewater were investigated.The results show that the optimum FeSO4 concentration and pH are 700 mg/L and 2.5,respectively,and the residual COD of wastewater decreases with the rise in H2O2 concentration,but increases with the rise in temperature.After Fenton's reagent treatment,the initial COD of less than 874 mg/L wastewater can meet effluent standard.Under conditions of 100 mg/L H2O2,437 mg/L initial COD and 15 ℃ temperature,the lowest residual COD is obtained at 83.80 mg/L in 5 min.

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.

载铜地质聚合物微球的制备及其催化降解双酚S的性能

传统的芬顿反应因在废水处理过程中会产生大量富含金属污泥而应用受限。本研究采用悬浮固化法得到了一种低成本、易回收、绿色的多孔地质聚合物微球(GM),将其作为载体通过浸渍法制备了载铜地质聚合物微球(Cu-GM),作为类芬顿反应催化剂,催化H_(2)O_(2)降解水中的双酚S(BPS)。SEM、XRD、BET和XPS等一系列表征结果表明,Cu^(+/2+)被稳定固定在GM表面。进一步探究了Cu-GM用量、H_(2)O_(2)用量、BPS浓度和溶液初始p H对催化降解的影响。结果表明,在优化条件下,Cu-GM在480min内对BPS的去除率可达99.3%,催化降解过程符合一级反应动力学。通过自由基淬灭实验发现,在催化降解过程中·OH和^(1)O_(2)是主要活性物质。循环实验表明Cu-GM具有良好的重复利用性,在去除水中有机污染物方面有着极大的应用潜力。

Use of Solid-Supported Reagents towards Synthesis of 2-Arylbenzoxazole, 3, 5-Diarylisoxazole and 1, 3, 5-Triarylpyrazole

Herein we report a convenient and efficient synthesis of 2-Arylbenzoxazole from the Schiff’s bases of 2-Aminophenol, 3, 5-Diarylisoxazole from α, β-unsaturated ketoxime and 1,3,5-Triarylpyrazole from 2-pyrazoline and N-Arylhydrazone by using milder, less toxic and less expensive-NBS-SiO2, KMnO4-Al2O3, PCC-SiO2 and ACC-Al2O3 as solid-supported oxidizing agents at room temperature. Within the framework of Green Chemistry, the use of solid supported reagents has many advantages such as 1) they are easy to remove from reactions by filtration 2) excess reagents can be used to drive the reaction without introducing any difficulties in purification 3) such solid-supported reagents react differently, mostly more selectively, than their unbound counterparts and 4) toxic, noxious and explosive chemicals are handled more safely when contained on solid support.

Fenton试剂法在工业有机废水中的处理研究

本文针对工业有机废水处理中的问题,探讨了Fenton试剂法在工业有机废水处理中的应用和处理策略。首先,分析了工业有机废水处理中的挑战,包括废水中有机物浓度高、毒性较强、处理难度大等问题。其次,介绍了Fenton试剂法的原理及特点。最后,探讨了Fenton试剂法在处理工业有机废水时的优化策略,以期为实际工程应用提供参考。

Fenton试剂液相氧化法净化含H_2S的气体

利用Fenton试剂液相氧化法净化含H2S的气体,研究了初始pH值、温度、H2S浓度、H2O2浓度、气体流量、[H2O2]/[Fe2+]比值、金属离子等因素对H2S去除率的影响.结果表明,当pH<2.52时,pH值升高,去除率逐渐提高;当pH>2.52时,去除率下降;pH=2.52时,去除效率最高.去除率随H2O2浓度增加而提高;H2O2浓度一定时,去除率随[H2O2]/[Fe2+]比值的增加而升高;[H2O2]/[Fe2+]接近于1时达到最大.温度提高,去除率提高.实验条件下,去除率随气体流量的增加而下降.入口H2S浓度越低去除率越高.Fe3+对Fenton反应有促进作用,添加金属离子的Fenton试剂氧化H2S能力顺序为Fe2++Fe3+>Fe2+>Fe3+.

US/Fenton氧化—混凝法对焦化废水的预处理研究

采用US/Fenton氧化—混凝法对高浓度焦化废水进行预处理。考察了对处理效果的影响因素,确定了最适工艺条件。结果表明,在超声波功率500 W,H2O2投加质量浓度为6.0 g/L,Fe2+为400 mg/L,pH 3,Al2(SO4)3、PAM投加量分别为480、4.0 mg/L的条件下,COD、NH3-N、CN-和色度的去除率分别达75.1%、53.4%、62.8%和83.1%,废水的COD由处理前的4 799 mg/L降至1 195 mg/L,BOD/COD由0.196提高到0.373,出水可生化性良好。US/Fenton氧化—混凝法可作为高浓度焦化废水的一种有效的预处理方法。

活性炭-Fenton组合法去除水中PAEs的研究

采用活性炭-Fenton组合方法催化氧化去除水中的邻苯二甲酸酯(PAEs),研究了H2O2、Fe2+、H2O2/Fe2+及活性炭的用量、pH值、反应时间以及PAEs的初始浓度等对水中PAEs去除率的影响.结果表明,在Fenton试剂与活性炭的协同作用下,对PAEs具有较好的去除效果.PAEs水溶液(DMP、DEP、DBP、DOP各为12 mg.L-1),经活性炭-Fenton法处理15 h后,PAEs的平均去除率可达到99.1%.

Fenton预氧化—SBR处理葡萄酒废水试验研究

葡萄酒废水是一种具有季节波动性的高COD、高色度有机废水,生产旺季时其水质水量的大幅度变化会给正常的好氧生化处理造成不利影响。研究了Fenton试剂预处理工艺对葡萄酒废水的处理效果及其主要控制参数。结果表明,Fenton试剂预处理对COD的去除率最高可达到54%。采用SBR对预处理出水进行好氧处理时,经过15 h的曝气,COD可降至40 mg/L以下,而未经Fenton氧化的废水曝气40 h后COD仍高达105 mg/L。高效液相色谱分析显示,葡萄酒废水的主要成分为乙醇、乙酸和酒石酸,经Fenton处理后,出水只检测到乙酸,显示Fenton预处理可改善原水水质,提高生化处理效果。

聚铁混凝-Fenton法-SBR工艺对成熟垃圾场渗滤液深度处理的研究

联合运用聚铁混凝、Fenton方法以及SBR生物法3种工艺对老龄垃圾场的渗滤液进行深度处理.在综合考虑出水符合垃圾渗滤液国家一级排放标准以及运行成本经济性的前提下,在进水主要污染物COD为640 mg.L-1、色度为500的条件下,推荐了聚铁混凝反应及Fenton反应的最优条件:聚铁加药量为0.45 mL.L-1,[Fe2+]投加量为0.006 mol.L-1,[H2O2]投加量为0.006 mol.L-1,反应时间4 h,Na2CO3投加量约为0.7 g.L-1,0.1%PAM投加量为2 mL.L-1,出水COD为68 mg.L-1,BOD为20mg.L-1.同时研究证明,在Fenton方法之前使用聚铁混凝法具有大幅度降低成本、省却pH调节步骤的优点.聚铁混凝反应及Fenton反应总药剂成本低于3.2元/t,实用价值高.Fenton反应后使用SBR生物法处理,其出水水质:COD≤80 mg.L-1,BOD≤8mg.L-1,NH4+-N≤3 mg.L-1,色度≤5倍,SS≤10 mg.L-1,符合垃圾渗滤液国家一级排放标准.

铁炭Fenton/SBR法处理硝基苯制药废水

为探寻硝基苯废水的适宜处理工艺，开展了铁炭Fentort／SBR工艺处理硝基苯制药废水的试验研究。结果表明，铁炭内电解结合Fenton氧化的预处理工艺可有效去除废水中的硝基苯类物质，并提高了废水的可生化性。当原水的pH值为2～3、H2O2投加量为500～600mg／L时，调节预处理出水pH值至7～8并经沉淀处理后，对COD和硝基苯类物质的总去除率分别可达47％和92％。后续混合废水经SBR工艺处理后出水水质能满足国家污水排放标准。

Fenton试剂氧化—SBR工艺处理阿莫西林制药废水生化处理出水

采用Fenton试剂氧化—SBR工艺处理阿莫西林制药废水生化处理出水。实验结果表明:当初始废水pH为3.0、H2O2加入量为10 mL/L、V(H2O2):m(FeSO4.7H2O)为5(mL):1(g)、Fenton试剂氧化反应时间为3 h时,Fenton试剂氧化COD去除率达72.25%,色度由100倍降为2倍,BOD5/COD由0.06提高到0.38,可生化性显著提高。经Fenton试剂氧化—SBR工艺处理后,出水COD为72.7 mg/L,达到国家排放标准。

US-Fenton法降解水中的己烯雌酚

采用超声（US）-Fenton试剂法降解水中的己烯雌酚（DES），用LC—MS／MS进行测定。考察了己烯雌酚初始浓度、反应时间、反应温度、溶液pH、超声功率和Fenton试剂对DES降解率的影响，优化了降解反应的工艺条件：O℃、pH为3．0、超声功率为200W、Fenton试剂中H202添加量为8％、FeSO4·7H2O添加量为0．2g／L时，处理初始浓度为200μg／L的DES，在反应50min后降解率可达85％。DES浓度在50-600μg／L范围时的降解速率符合一级反应动力学。

Fenton氧化—混凝—SBR工艺处理糠醛废水

采用Fenton氧化－混凝－SBR工艺处理糠醛废水。实验结果表明：Fenton氧化－混凝预处理糠醛废水时，在废水中硫酸亚铁和过氧化氢浓度分别为57．60mmol／L和5．22mol／L、pH为2—3的条件下，废水处理后COD可达500mg／L以下；再经SBR工艺处理，水力停留时间为18h，最终出水COD去除率可达99．67％。