Fenton及改进Fenton氧化处理难降解有机废水的研究进展

介绍了在难降解有机废水处理方面具有良好前景的Fenton氧化技术,重点探讨了Fenton、超声-Fenton、电-Fenton、光-Fenton、超声-光-Fenton、光-电-Fenton、非均相纳米催化-Fenton氧化技术的机理、特点及其主要应用研究现状。此外,展望了Fenton及改进Fenton氧化技术的发展趋势和研究重点。     

Fenton试剂氧化机理及印染废水处理研究进展

系统的分析了Fenton试剂、光助-Fenton、电-Fenton、超声-Fenton对有机污染物的降解机理,概述了Fenton氧化以及Fenton氧化与其它处理方法组合使用的技术在印染废水中的处理的运用,Fenton法对印染废水的色度和COD能够进行有效的去除,总结了Fenton氧化技术的发展历程,提出了Fenton氧化技术将沿着类Fenton以及和其他方法组合的方向发展。     

Fenton氧化法处理废水的机理及应用

阐述了Fenton试剂的氧化机理 ,分析了各项因素对氧化效果的影响。介绍了光 -Fenton法、电 -Fenton法及Fenton -混凝法在废水处理中应用情况以及存在的问题 ,并展望了其发展趋势。     

Fenton法在垃圾渗滤液处理中的应用及研究进展

垃圾渗滤液尤其是长龄渗滤液很难通过单一的生化法实现有效处理,研究显示,Fenton氧化技术是一种应用和研究最多、处理效果最好的物化方法。为了进一步克服该法的缺陷并充分发挥其优势,近期的研究多对传统的Fenton氧化技术进行了技术优化和改进,并指出高效的电-Fenton法、光-Fenton法降解机制的深入研究以及其操作条件的优化将是日后的重点所在。     

非均相光-Fenton技术在水处理领域的研究进展

非均相光-Fenton技术是基于传统Fenton试剂法,通过引入光照和新型催化剂实现光催化氧化和Fenton反应的协同作用,促进活性自由基(如·OH)的生成和有机物高效降解的新型高级氧化技术。综述了非均相光-Fenton体系的技术特征、关键影响因素和氧化原理,详细阐述了铁物种与二氧化钛、石墨相氮化碳、氧化石墨烯/还原氧化石墨烯、钒酸铋以及三氧化钨不同类型半导体结合的非均相光-Fenton材料的光催化氧化原理和有机物降解机制。     

Fenton法的氧化机理及在废水处理中的应用进展

阐述了普通Fenton法、光-Fenton法和电-Fenton法的原理及应用,并对各种类型的Fenton法的优势,问题及发展趋势作了评述,尤其介绍了它和其它技术(生物法、混凝法、吸附法)联用的优势及应用情况.     

焦化废水深度处理研究进展

焦化废水含有大量有机污染物和有毒无机物,成分复杂,污染物色度高,属较难生化降解的高浓度有机工业废水.经常规方法预处理,再经生化处理后的焦化废水存在氰化物、COD及氨氮等不达标的问题.通过臭氧氧化法、Feton试剂氧化法以及光催化氧化法等高级氧化法,活性炭以及矿物吸附法等三级深度处理可以解决这一问题.介绍了目前焦化废水深度处理的研究进展并进行了展望.     

Fenton氧化技术与其他方法联用在废水处理方面的研究进展

综述了近些年Fenton氧化技术与其他方法联用在处理难降解有机废水方面的研究进展。重点探讨了吸附-Fenton氧化技术、混凝-Fenton氧化技术、微波-Fenton氧化技术、生物方法 -Fenton氧化技术的特点及其应用研究现状,指出了这些联用技术可改进的地方。此外,展望了联用方法的发展趋势。     

Fenton氧化技术与其他方法联用在废水处理方面的研究进展

综述了近些年Fenton氧化技术与其他方法联用在处理难降解有机废水方面的研究进展,探讨了吸附-Fenton氧化技术、混凝-Fenton氧化技术、微波-Fenton氧化技术、生物方法-Fenton氧化技术的特点及其应用研究现状,指出了这些联用技术可改进的地方。此外,展望了联用方法的发展趋势。     

芬顿法在水处理中的发展与现状

随着水处理技术的不断优化,针对污水中的有机污染物难以降解的问题,芬顿氧化法被广泛用于各种难降解废水的处理中。从均相芬顿法和非均相芬顿法两个方面介绍了不同种类的芬顿氧化法的发展现状以及技术特点。均相芬顿氧化法主要介绍了电-芬顿法、光-芬顿法、微波芬顿氧化法、超声波芬顿法;非均相芬顿氧化法主要介绍了有机载体催化剂体系、无极材料负载型催化剂以及铁氧化物负载催化剂,并提出了一些建议和展望。     

Degradation of 4-chloro-2-methylphenol in aqueous solution by electro-Fenton and photoelectro-Fenton processes

Degradation of 4-chloro-2-methylphenol (PCOC), a refractory toxic chemical emitted to the environment from the industrial production of phenoxy herbicides was studied in aqueous solution. Electro-Fenton and photoelectro-Fenton processes were used as the degradation methods. H₂O₂, produced by the reduction of oxygen at carbon cathode reacted with dissolved metal ions to form hydroxyl radicals, which in turn reacted with PCOC sequentially to degrade the aromatic ring. The effects of using different [Fe²⁺]/[PCOC]₀ and the effect of replacing Fe²⁺ by Mn²⁺ ion have been examined. It was found that degradation rate was increased with increasing [Fe²⁺]/[PCOC]₀ ratio from 2 to 4. However, the total charge utilized during the treatment was also increased. The efficiency of PCOC degradation was observed to be higher when Mn²⁺ was used as the catalyst. The mineralization of aqueous solutions of PCOC, withdrawn from the reactor at certain time interval, has been followed by total organic carbon (TOC) decay and dechlorination. A fast and complete degradation of the aromatic ring was achieved in photoelectro-Fenton system. 41.7% TOC decay and complete dechlorination were observed by consuming only 141.4 C electrical charge during a 300 min photoelectron-Fenton treatment. In the case of electro-Fenton system, 280.7 C electrical charge was consumed during 450 min of electrolysis to attain a similar degradation of PCOC. 14.9% TOC removal and 89.3% dechlorination have been obtained in this system under the applied conditions.     

Electro-Fenton, UVA photoelectro-Fenton and solar photoelectro-Fenton degradation of the drug ibuprofen in acid aqueous medium using platinum and boron-doped diamond anodes

The degradation of a 41 mg dm⁻³ ibuprofen (2-(4-isobutylphenyl)propionic acid) solution of pH 3.0 has been comparatively studied by electrochemical advanced oxidation processes (EAOPs) like electro-Fenton, UVA photoelectro-Fenton and solar photoelectro-Fenton at constant current density. Experiments were performed in a one-compartment cell with a Pt or boron-doped diamond (BDD) anode and an O₂-diffusion cathode. Heterogeneous hydroxyl radical (OH) is generated at the anode surface from water oxidation, while homogeneous OH is formed from Fenton's reaction between Fe²⁺ and H₂O₂ generated at the cathode, being its production strongly enhanced from photo-Fenton reaction induced by sunlight. Higher mineralization is attained in all methods using BDD instead Pt, because the former produces greater quantity of OH enhancing the oxidation of pollutants. The mineralization rate increases under UVA and solar irradiation by the rapid photodecomposition of complexes of Fe(III) with acidic intermediates. The most potent method is solar photoelectro-Fenton with BDD giving 92% mineralization due to the formation of a small proportion of highly persistent final by-products. The effect of Fe²⁺ content, pH and current density on photoelectro-Fenton degradation has been studied. The ibuprofen decay always follows a pseudo-first-order kinetics and its destruction rate is limited by current density and UV intensity. Aromatics such as 1-(1-hydroxyethyl)-4-isobutylbenzene, 4-isobutylacetophenone, 4-isobutylphenol and 4-ethylbenzaldehyde, and carboxylic acids such as pyruvic, acetic, formic and oxalic have been identified as oxidation by-products. Oxalic acid is the ultimate by-product and the fast photodecarboxylation of its complexes with Fe(III) under UVA or solar irradiation explains the higher oxidation power of photoelectro-Fenton methods in comparison to electro-Fenton procedures.     

Mineralization of clofibric acid by electrochemical advanced oxidation processes using a boron-doped diamond anode and Fe and UVA light as catalysts

This work shows that aqueous solutions of clofibric acid (2-(4-chlorophenoxy)-2-methylpropionic acid), the bioactive metabolite of various lipid-regulating drugs, up to saturation at pH 3.0 are efficiently and completely degraded by electrochemical advanced oxidation processes such as electro-Fenton and photoelectro-Fenton with Fe²⁺ and UVA light as catalysts using an undivided electrolytic cell with a boron-doped diamond (BDD) anode and an O₂-diffusion cathode able to electrogenerate H₂O₂. This is feasible in these environmentally friendly methods by the production of oxidant hydroxyl radical at the BDD surface from water oxidation and in the medium from Fenton's reaction between Fe²⁺ and electrogenerated H₂O₂. The degradation process is accelerated in photoelectro-Fenton by additional photolysis of Fe³⁺ complexes under UVA irradiation. Comparative treatments by anodic oxidation with electrogenerated H₂O₂, but without Fe²⁺, yield much slower decontamination. Chloride ion is released and totally oxidized to chlorine at the BDD surface in all treatments. The decay kinetics of clofibric acid always follows a pseudo-first-order reaction. 4-Chlorophenol, 4-chlorocatechol, hydroquinone, p-benzoquinone and 2-hydroxyisobutyric, tartronic, maleic, fumaric, formic and oxalic acids, are detected as intermediates. The ultimate product is oxalic acid, which is slowly but progressively oxidized on BDD in anodic oxidation. In electro-Fenton this acid forms Fe³⁺–oxalato complexes that can also be totally destroyed at the BDD anode, whereas in photoelectro-Fenton the mineralization rate of these complexes is enhanced by its parallel photodecarboxylation with UVA light.     

石墨烯基光催化复合材料研究进展

简单介绍石墨烯的结构和性质,简述石墨烯及石墨烯基光催化复合材料的制备方法,对近些年石墨烯基光催化复合材料在染料降解、有机污染物氧化、无机污染物处理、CO2还原、光催化裂解水产氢方面的研究进行综述。     

Mineralization of an azo dye Acid Red 14 by photoelectro-Fenton process using an activated carbon fiber cathode

The mineralization of an azo dye Acid Red 14 (AR14) by the photoelectro-Fenton (PEF) process was studied in an undivided electrochemical reactor with a RuO₂/Ti anode and an activated carbon fiber (ACF) cathode able to electrochemically generate H₂O₂. Anodic oxidation and UV irradiation of AR14 were also examined as comparative experiments. Results indicate that the electro-Fenton process yielded about 60–70% mineralization of AR14, while the photoelectro-Fenton could mineralize AR14 more effectively (more than 94% total organic carbon (TOC) removal) even at low current densities assisted with UV irradiation after 6 h electrolysis. The mineralization current efficiency (MCE) of the PEF process increased with the increasing AR14 concentrations. In addition, the initial solution pH ranging from 1.49 to 6.72 had little influence on the TOC removal probably due to the formation of organic carboxylic acids which balanced the pH increase caused by the cathodic generation of hydrogen gas. The ACF cathode showed a long-term stability during multiple experimental runs for degradation of AR14, indicating its good potential for practical application in treating refractory organic pollutants in aqueous solutions.     

Electrochemical removal of gallic acid from aqueous solutions

Removal of gallic acid from aqueous solutions of different concentrations has been performed by electroprecipitation using a sacrificial iron anode, by indirect electrochemical oxidation carried out via electro- and photoelectro-Fenton processes using an oxygen-diffusion cathode, and by a combination of the first two methods (peroxicoagulation process). In all cases, chromatographic analyses have shown a very quick disappearance of gallic acid and its aromatic by-products within 30-90 min of electrolysis, depending on the method. A pseudo first-order kinetic decay of gallic acid was always observed under galvanostatic conditions. A decay of TOC and COD close to 90 and 95% is observed with electroprecipitation and peroxicoagulation processes, respectively, after electrolysis time lower than 2 h. The specific charge utilised in these two processes was about half of that theoretically required for the complete direct oxidation process (mineralisation). During electrolyses some carboxylic acids have been detected as main intermediates, which completely disappear at the end of the process, except oxalic acid in the case of electro-Fenton method.     

电催化氧化处理难降解有机废水的研究进展

生物难降解有机物是水处理中的难题之一。本文综述了目前国内外电催化氧化处理该类废水的应用现状及研究方向展望。     

ε-酸在超临界水中的氧化降解

实验研究了典型有机污染物ε -酸在超临界水中的氧化降解.结果表明,超临界水氧化技术能有效地降解废水中的有机污染物,COD去除率可达99%以上.随着反应温度的升高、压力的增大、停留时间的延长和初始废水浓度的增大,COD去除率也随之提高.ε-酸在超临界水中氧化降解的动力学方程为:-d[COD]/dt =9.75104exp(-8.3804/RT)[COD]1.06[O2]00.165     

氨氮与2-氨基吡啶在三维电催化氧化降解中的竞争

采用CuO-ZnO/多孔陶瓷为粒子电极的三维电催化氧化技术,对氨氮与2-氨基吡啶模拟废水的电催化氧化降解中的竞争过程进行研究。考察了氨氮及氨氮与2-氨基吡啶直接氧化和间接氧化降解的情况,并分析了氨氮与2-氨基吡啶的竞争反应过程。结果表明:间接氧化过程更有利于氨氮的去除,并可降低硝酸盐氮的累积率,2-氨基吡啶主要通过直接氧化降解,不受氨氮和氯离子的影响,直接氧化条件下2-氨基吡啶开环产物与氨氮存在强烈的竞争现象,间接氧化对2-氨基吡啶开环产物与氨氮的降解都有提高,且氨氮的去除优先于2-氨基吡啶开环产物。因此,可以通过改变三维电催化体系的直接和间接氧化条件,调整氨氮与有机物的去除效果,并可应用于含氨氮有机废水处理的现场调试。     

电催化与紫外光辐射降解氯酚

Chlorinated organic compounds, especially chlorophenols are well-known water priority pollutant family due to their toxicity and potential health hazard. As biological treatment processes for the degradation of chlorinated phenols have not been effective, various technologies and processes such as activated carbon adsorption[1], chemical oxidation[2], have been conventionally attempted for phenolic waster treatment. Recently, advanced oxidation processes (AOPs) have attracted a great deal of attention for treatment of phenolic wastewater, among these chemical oxidation ultraviolet (UV) oxidation system[3], anodic oxidation and indirect electro-oxidation have been widely studied[4]. Though a number of researchers worked on the degradation of chlorophenol by UV radiation or electrochemical processes, there are few reports on both methods for organic wastewater treatment. If these two processes can operate in harmony, the degradation efficiency would be enhanced.