The degradation and mineralization of aniline （AN） using ozone combined with Fenton reagent （O3/Fenton） in a rotating packed bed （RPB） was proposed in this study, and the process （RPB-O3/Fenton） was compared w...The degradation and mineralization of aniline （AN） using ozone combined with Fenton reagent （O3/Fenton） in a rotating packed bed （RPB） was proposed in this study, and the process （RPB-O3/Fenton） was compared with conventional O3/Fenton in a stirred tank reactor （STR-O3/Fenton） or single ozonation in an RPB （RPB-O3）, Effects of high gravity factor, H2O2 dosage, H2O2 dosing method and initial pH on the AN mineralization efficiency were investigated in the RPB-O3/Fenton process, In addition, the behavior of Fe（Ⅱ） was monitored at different H2O2 dosing methods and pH values. Finally, the optimal operation conditions were determined with high gravity factor of 100, initial pH of 5, Fe（Ⅱ） concentration of 0.8 mmol·L-1 and H2O2 dosage of 2.5 ml. Under these conditions, for aniline wastewater at the volume of I L and concentration of 200 mg· L- 1 ,a fast and thorough decay of AN was conducted in 10 min, and the TOC removal efficiency reached 89% in 60 min. The main intermediates of p-benzoquinone, nitrobenzene, maleic acid and oxalic acid were identified by liquid chromatography/mass spectroscopy （LC/MS）, and the degradation pathways of AN in RPB-O3/Fenton system were proposed based on experimental evidence. It could be envisioned that high-gravity technology combined with O3/Fenton processes would be promising in the rapid and efficient mineralization ofwastewater.展开更多
Both citrate and hypophosphite in aqueous solution were degraded by advanced oxidation processes （Fe^2＋/H2O2, UV/Fe^2＋/H2O2, and electrolysis/Fe^2＋/H2O2） in this study. Comparison of these techniques in oxidation...Both citrate and hypophosphite in aqueous solution were degraded by advanced oxidation processes （Fe^2＋/H2O2, UV/Fe^2＋/H2O2, and electrolysis/Fe^2＋/H2O2） in this study. Comparison of these techniques in oxidation efficiency was undertaken. It was found that Fenton process could not completely degrade citrate in the presence of hypophosphite since it caused a series inhibition. Therefore, UV light （photo-Fenton） or electron current （electro-Fenton） was applied to improve the degradation efficiency of the Fenton process. Results showed that both photo-Fenton and electro-Fenton processes could overcome the inhibition of hypophosphite, especially the electro-Fenton.展开更多
In this paper, Fenton process was determined to be an effective technique to treat the refractory Nonylphenol ethoxylates (NPEOs) wastewater. The COD removal efficien-cies above 89% were obtained when the initial COD ...In this paper, Fenton process was determined to be an effective technique to treat the refractory Nonylphenol ethoxylates (NPEOs) wastewater. The COD removal efficien-cies above 89% were obtained when the initial COD concentration was 12000mg/L. However, A large number of ferric sludge (SS=8.724g/L) would be produced after the Fenton oxidation of the wastewater and must be disposed appropriately. A novel process for Fenton sludge reused by low-cost ferrous sulfide (FeS) was also investi-gated. Experimental results show that the Fenton sludge could be reduced to produce a certain amount of Fe2+ in the acidic mixed liquor by ferrous sulfide. This mixed liquor from Fenton sludge could be used as the new catalyst in the Fenton process and was also highly effective for the NPEOs wastewater treatment. The residual ferrous sulfide from the mixed liquor could be used for the next batch of the展开更多
In this work, the degradation of 2-chloro-4,6-diamino-1,3,5-triazine in aqueous solutions by photo-Fenton process has been investigated. The preliminary results have shown that the degradation of 2-chloro-4,6-diamino-...In this work, the degradation of 2-chloro-4,6-diamino-1,3,5-triazine in aqueous solutions by photo-Fenton process has been investigated. The preliminary results have shown that the degradation of 2-chloro-4,6-diamino-1,3,5-triazine by photo-Fenton process is more rapid and more effective than Fenton and UV/H2O2 processes. The effects of certain experimental parameters on kinetics and efficiency of the degradation of 2-chloro-4,6,-diamino-1,3,5-triazine by photo-Fenton process, have been evaluated. Under optimal conditions, photo-Fenton process achieved more than 90% of chloride release and about 30% of nitrate formation. The results of total organic carbon (TOC) and total Kjeldahl nitrogen (TKN) analyses have shown that no carbon dioxide and ammonia are formed during photo-Fenton treatment of aqueous solutions containing 40 mg/L triazine. These results indicate that only substituent groups of triazine ring are released;however, nitrogen atoms of triazine ring remain unaffected. A simple mechanism of degradation of 2-chloro-4,6-diamino-1,3,5-triazine has been proposed. The degradation starts by a rapid release of chlorine atoms as chloride ions to form 2-hydroxy-4,6-diamino-1,3,5-triazine. The amino groups of 2-hydroxy-4,6-diamino-1,3,5-triazine undergo are oxidized into nitro groups by hydroxyl radicals to form 2-hydroxy-4,6-dinitro-1,3,5-triazine which undergoes a slow release of nitro groups and their substitution with hydroxyl groups to form cyanuric acid and nitrate ions. The degradation of cyanuric acid by photo-Fenton process has also been investigated. The results of TOC and TKN analyzes show that no carbon dioxide is formed during the treatment.展开更多
Efficient management of temporal latency and spatial heterogeneity remains a critical challenge in sensor-based pH regulation for smart water management,primarily due to inherent response delays and mass transfer cons...Efficient management of temporal latency and spatial heterogeneity remains a critical challenge in sensor-based pH regulation for smart water management,primarily due to inherent response delays and mass transfer constraints.In oxidation systems with dynamic pH environments,delayed responses can lead to issues such as cyanide release,unwanted side reactions,or pipe damage.To address these challenges,we propose a“pause-then-adjust”control strategy,exploiting the pH-responsive generation of hydroxyl radicals(·OH)in a modified Fenton reaction system.This system utilizes hydroxylamine as an electron donor and ethylenediaminetetraacetic acid(EDTA)as a stabilizer for iron ions.Within the pH range of 7.0-10.0,the coexistence of[Fe^(2+)-EDTA]^(2-) and[Fe^(3+)-OH-EDTA]^(2-) complexes facilitates efficient electron transfer,resulting in the selective and sustained production of ·OH radicals.The inherent pHresponsiveness of this strategy enables rapid and spatially coherent adjustments,offering a robust supplementary method for addressing complex and evolving requirements in advanced water treatment systems.展开更多
The applicability of the life cycle assessment(LCA)to the Fenton process should be considered not only at the laboratory-scale but also at the full-scale.In this study,the LCA process was applied to evaluate the homo-...The applicability of the life cycle assessment(LCA)to the Fenton process should be considered not only at the laboratory-scale but also at the full-scale.In this study,the LCA process was applied to evaluate the homo-geneous Fenton process for the treatment of high salinity pharmaceutical wastewater.The potential environmental impacts were calculated using Simapro software implemen-ting the CML 2001 methodology with normalization factors of 1995 world.Foreground data obtained directly from the full-scale wastewater treatment plant and labora-tory were used to conduct a life cycle inventory analysis,ensuring highly accurate results.By normalized results,the Fenton process reveals sensitive indicators,primarily toxi-city indicators(human toxicity,freshwater aquatic toxicity,and marine aquatic toxicity),as well as acidification and eutrophication impacts,contributed by hydrogen peroxide and iron sludge incineration,respectively.Overall,hydrogen peroxide and iron sludge incineration contribute significantly,accounting for at least 78%of these indicators.In sludge treatment phase,treatment of iron mud and infrastructure of hazardous waste incineration plants were the key contributors of environmental impacts,adding up to more than 95%.This study suggests the need to develop efficient oxidation processes and effective iron sludge treatment methods to reduce resource utilization and improve environmental benefits.展开更多
ZnFe2O4 nanoparticles （ZFNPs） were developed as catalyst for the degradation of benzotriazole （BTA） by heterogeneous photoelectro- Fenton （PE-Fenton） like process. ZFNPs were prepared by a co-precipitation proce...ZnFe2O4 nanoparticles （ZFNPs） were developed as catalyst for the degradation of benzotriazole （BTA） by heterogeneous photoelectro- Fenton （PE-Fenton） like process. ZFNPs were prepared by a co-precipitation process and then characterized with transmission electron microscopy （TEM）, X-ray fluorescence （XRF）, X-ray diffraction （XRD） and BET surface area. Using such ZFNPs as catalyst, the degradation of BTA was investigated. Due to the high catalytic activity of ZFNPs, PE-Fenton like process showed efficient degradation of BTA. The influencing factors such as pH, dosage of ZFNPs, applied potential and initial concentration of BTA were systematically investigated. Under the optimum conditions, 91.2% of BTA was removed after 180 rain treatment.展开更多
A combined treatment technology （DEF-BIO） using the direct electro-Fenton （DEF） process and bioremediation （BIO） was established in this study. The performance of the DEF-BIO process on the remediation of a pyre...A combined treatment technology （DEF-BIO） using the direct electro-Fenton （DEF） process and bioremediation （BIO） was established in this study. The performance of the DEF-BIO process on the remediation of a pyrene （PYR）-contaminated soil was evaluated in a slurry reactor. The appropriate order of application was to conduct the DEF process followed by BIO, evaluated through analysis of the degradation characteristics of each process individually. In addition, the application time of the DEF process affected the efficiency of the combined process. The optimum time to apply the DEF process was determined through an analysis of the induced changes in PYR intermediates, pH, soil organic matter （SOM） and bacteria. The optimum application time of the DEF process was 6 h. All the induced changes were beneficial for the BIO phase. The removal of PYR was 91.02% for DEF- BIO after 72h, and the efficiency was almost 50% increased, compared with the individual DEF and BIO treatments. Therefore, the combined process of DEF-BIO process may be an efficient and promising method for the remediation.展开更多
The advanced treatment using integrated Fenton＇s reaction and coagulation process was investigated in this study. Before the advancement, the pharmaceutical wastewater containing lincomycin hydrochloride was pretreat...The advanced treatment using integrated Fenton＇s reaction and coagulation process was investigated in this study. Before the advancement, the pharmaceutical wastewater containing lincomycin hydrochloride was pretreated by UASB （upflow anaerobic sludge bed） and a SBR （sequencing batch reactor） process. The residual recalcitrant compounds, measured by gas chromatographymass spectrometry （GC-MS）, mainly consisted of alcohols, phenols, and nitrogenous and sulfur compounds. The experimental results indicated that when the Fenton＇s reaction was conducted at pH=3.0, H2O2CODOcr=0.27, H2O2/Fe^2＋=3：1 and 30 min of reaction time, and the coagulation process operated at a sulfate aluminum concentration of 800 mg/L and pH value of 5.0, the color and COD in the wastewater decreased by 94% and 73%, respectively; with a finale COD concentration of 267 mg/L and color level of 40 units, meeting the secondary standard of GB8978-1996 for industrial wastewater.展开更多
Kinetics of homogeneous degradation of Eosin Y (EY), also known as Acid red 87 (CI 45380), are studied, mostly using Fenton’s process, at 30℃ by monitoring its absorbance at 517 nm (λ<sub>max</sub> of E...Kinetics of homogeneous degradation of Eosin Y (EY), also known as Acid red 87 (CI 45380), are studied, mostly using Fenton’s process, at 30℃ by monitoring its absorbance at 517 nm (λ<sub>max</sub> of EY). This process is one of the advanced oxidation processes (AOPs). Mixture of H<sub>2</sub>O<sub>2</sub> and Fe(II) ion in acetate buffer medium (pH 2.74 - 4.56) generates hydroxyl free radicals (?OH) which attack the dye molecules, resulting in degradation of the dye molecules. Results show that the initial rate of EY degradation decreases with the increasing of solution pH because of removal of kinetically important Fe (iron) species through formation of ferric hydroxide. On the other hand, the rate increases with increasing the concentrations of H<sub>2</sub>O<sub>2</sub>, Fe(II) and EY at low solution pH. The initial rate increases with increasing of concentration of H2O2 and, subsequently remains unaffected with further increase of its concentration at a constant Fe(II) concentration because of the enhanced scavenging environment created by H<sub>2</sub>O<sub>2</sub> at its higher concentration. The initial rate also increases with increasing of concentration of Fe(II) at a constant H<sub>2</sub>O<sub>2</sub> concentration and remains unaffected with its further increase. EY concentration also enhances the initial rate at low pH. However, the initial rate is significantly enhanced by UV light. This is because of formation of additional hydroxyl radicals through excitation of the dye molecules by UV light. During the period of experiment, EY in aqueous solution alone hardly suffered any degradation. Degradation mechanism of EY by the Fenton and photo-Fenton’s processes is also discussed. Statistical analysis was used to validate the experimental results. Low values of the standard deviation for both the initial rate and % degradation indicated the consistency of the experimental data.展开更多
基金Supported by the National Natural Science Foundations of China(U1610106)Shanxi Excellent Talent Science and Technology Innovation Project(201705D211011)+1 种基金Specialized Research Fund for Sanjin Scholars Program of Shanxi ProvinceNorth University of China Fund for Distinguished Young Scholars
文摘The degradation and mineralization of aniline （AN） using ozone combined with Fenton reagent （O3/Fenton） in a rotating packed bed （RPB） was proposed in this study, and the process （RPB-O3/Fenton） was compared with conventional O3/Fenton in a stirred tank reactor （STR-O3/Fenton） or single ozonation in an RPB （RPB-O3）, Effects of high gravity factor, H2O2 dosage, H2O2 dosing method and initial pH on the AN mineralization efficiency were investigated in the RPB-O3/Fenton process, In addition, the behavior of Fe（Ⅱ） was monitored at different H2O2 dosing methods and pH values. Finally, the optimal operation conditions were determined with high gravity factor of 100, initial pH of 5, Fe（Ⅱ） concentration of 0.8 mmol·L-1 and H2O2 dosage of 2.5 ml. Under these conditions, for aniline wastewater at the volume of I L and concentration of 200 mg· L- 1 ,a fast and thorough decay of AN was conducted in 10 min, and the TOC removal efficiency reached 89% in 60 min. The main intermediates of p-benzoquinone, nitrobenzene, maleic acid and oxalic acid were identified by liquid chromatography/mass spectroscopy （LC/MS）, and the degradation pathways of AN in RPB-O3/Fenton system were proposed based on experimental evidence. It could be envisioned that high-gravity technology combined with O3/Fenton processes would be promising in the rapid and efficient mineralization ofwastewater.
基金The authors thank the "National" Science Council, Taiwan, China for financially supporting (No. NSC95- 2211-E-006-032).
文摘Both citrate and hypophosphite in aqueous solution were degraded by advanced oxidation processes （Fe^2＋/H2O2, UV/Fe^2＋/H2O2, and electrolysis/Fe^2＋/H2O2） in this study. Comparison of these techniques in oxidation efficiency was undertaken. It was found that Fenton process could not completely degrade citrate in the presence of hypophosphite since it caused a series inhibition. Therefore, UV light （photo-Fenton） or electron current （electro-Fenton） was applied to improve the degradation efficiency of the Fenton process. Results showed that both photo-Fenton and electro-Fenton processes could overcome the inhibition of hypophosphite, especially the electro-Fenton.
文摘In this paper, Fenton process was determined to be an effective technique to treat the refractory Nonylphenol ethoxylates (NPEOs) wastewater. The COD removal efficien-cies above 89% were obtained when the initial COD concentration was 12000mg/L. However, A large number of ferric sludge (SS=8.724g/L) would be produced after the Fenton oxidation of the wastewater and must be disposed appropriately. A novel process for Fenton sludge reused by low-cost ferrous sulfide (FeS) was also investi-gated. Experimental results show that the Fenton sludge could be reduced to produce a certain amount of Fe2+ in the acidic mixed liquor by ferrous sulfide. This mixed liquor from Fenton sludge could be used as the new catalyst in the Fenton process and was also highly effective for the NPEOs wastewater treatment. The residual ferrous sulfide from the mixed liquor could be used for the next batch of the
文摘In this work, the degradation of 2-chloro-4,6-diamino-1,3,5-triazine in aqueous solutions by photo-Fenton process has been investigated. The preliminary results have shown that the degradation of 2-chloro-4,6-diamino-1,3,5-triazine by photo-Fenton process is more rapid and more effective than Fenton and UV/H2O2 processes. The effects of certain experimental parameters on kinetics and efficiency of the degradation of 2-chloro-4,6,-diamino-1,3,5-triazine by photo-Fenton process, have been evaluated. Under optimal conditions, photo-Fenton process achieved more than 90% of chloride release and about 30% of nitrate formation. The results of total organic carbon (TOC) and total Kjeldahl nitrogen (TKN) analyses have shown that no carbon dioxide and ammonia are formed during photo-Fenton treatment of aqueous solutions containing 40 mg/L triazine. These results indicate that only substituent groups of triazine ring are released;however, nitrogen atoms of triazine ring remain unaffected. A simple mechanism of degradation of 2-chloro-4,6-diamino-1,3,5-triazine has been proposed. The degradation starts by a rapid release of chlorine atoms as chloride ions to form 2-hydroxy-4,6-diamino-1,3,5-triazine. The amino groups of 2-hydroxy-4,6-diamino-1,3,5-triazine undergo are oxidized into nitro groups by hydroxyl radicals to form 2-hydroxy-4,6-dinitro-1,3,5-triazine which undergoes a slow release of nitro groups and their substitution with hydroxyl groups to form cyanuric acid and nitrate ions. The degradation of cyanuric acid by photo-Fenton process has also been investigated. The results of TOC and TKN analyzes show that no carbon dioxide is formed during the treatment.
基金supported by the National Natural Science Foundation of China(No.52400097)the Open Project of State Key Laboratory of Urban Water Resource and Environment from Harbin Institute of Technology(No.QA202446)the Nanqiang Young Talents Supporting Program from Xiamen University.
文摘Efficient management of temporal latency and spatial heterogeneity remains a critical challenge in sensor-based pH regulation for smart water management,primarily due to inherent response delays and mass transfer constraints.In oxidation systems with dynamic pH environments,delayed responses can lead to issues such as cyanide release,unwanted side reactions,or pipe damage.To address these challenges,we propose a“pause-then-adjust”control strategy,exploiting the pH-responsive generation of hydroxyl radicals(·OH)in a modified Fenton reaction system.This system utilizes hydroxylamine as an electron donor and ethylenediaminetetraacetic acid(EDTA)as a stabilizer for iron ions.Within the pH range of 7.0-10.0,the coexistence of[Fe^(2+)-EDTA]^(2-) and[Fe^(3+)-OH-EDTA]^(2-) complexes facilitates efficient electron transfer,resulting in the selective and sustained production of ·OH radicals.The inherent pHresponsiveness of this strategy enables rapid and spatially coherent adjustments,offering a robust supplementary method for addressing complex and evolving requirements in advanced water treatment systems.
基金The funds for this research were provided by the National Key Research and Development Program of China(Grant No.2019YFA0705800)the National Natural Science Foundation of China(Grant No.21876049)+2 种基金the Shanghai Pujiang Program(Grant No.21PJD016)the Shanghai Technology Innovation Program for Carbon Neutrality(Grant No.21DZ1207800)the Shanghai Technology Innovation Program of Technical Center(Grant No.20DZ2250600).
文摘The applicability of the life cycle assessment(LCA)to the Fenton process should be considered not only at the laboratory-scale but also at the full-scale.In this study,the LCA process was applied to evaluate the homo-geneous Fenton process for the treatment of high salinity pharmaceutical wastewater.The potential environmental impacts were calculated using Simapro software implemen-ting the CML 2001 methodology with normalization factors of 1995 world.Foreground data obtained directly from the full-scale wastewater treatment plant and labora-tory were used to conduct a life cycle inventory analysis,ensuring highly accurate results.By normalized results,the Fenton process reveals sensitive indicators,primarily toxi-city indicators(human toxicity,freshwater aquatic toxicity,and marine aquatic toxicity),as well as acidification and eutrophication impacts,contributed by hydrogen peroxide and iron sludge incineration,respectively.Overall,hydrogen peroxide and iron sludge incineration contribute significantly,accounting for at least 78%of these indicators.In sludge treatment phase,treatment of iron mud and infrastructure of hazardous waste incineration plants were the key contributors of environmental impacts,adding up to more than 95%.This study suggests the need to develop efficient oxidation processes and effective iron sludge treatment methods to reduce resource utilization and improve environmental benefits.
基金supported by the National Natural Science Foundation of China (No. 20977037)the Fundamental Research Funds for the Central Universities (No.2011TS062)
文摘ZnFe2O4 nanoparticles （ZFNPs） were developed as catalyst for the degradation of benzotriazole （BTA） by heterogeneous photoelectro- Fenton （PE-Fenton） like process. ZFNPs were prepared by a co-precipitation process and then characterized with transmission electron microscopy （TEM）, X-ray fluorescence （XRF）, X-ray diffraction （XRD） and BET surface area. Using such ZFNPs as catalyst, the degradation of BTA was investigated. Due to the high catalytic activity of ZFNPs, PE-Fenton like process showed efficient degradation of BTA. The influencing factors such as pH, dosage of ZFNPs, applied potential and initial concentration of BTA were systematically investigated. Under the optimum conditions, 91.2% of BTA was removed after 180 rain treatment.
文摘A combined treatment technology （DEF-BIO） using the direct electro-Fenton （DEF） process and bioremediation （BIO） was established in this study. The performance of the DEF-BIO process on the remediation of a pyrene （PYR）-contaminated soil was evaluated in a slurry reactor. The appropriate order of application was to conduct the DEF process followed by BIO, evaluated through analysis of the degradation characteristics of each process individually. In addition, the application time of the DEF process affected the efficiency of the combined process. The optimum time to apply the DEF process was determined through an analysis of the induced changes in PYR intermediates, pH, soil organic matter （SOM） and bacteria. The optimum application time of the DEF process was 6 h. All the induced changes were beneficial for the BIO phase. The removal of PYR was 91.02% for DEF- BIO after 72h, and the efficiency was almost 50% increased, compared with the individual DEF and BIO treatments. Therefore, the combined process of DEF-BIO process may be an efficient and promising method for the remediation.
文摘The advanced treatment using integrated Fenton＇s reaction and coagulation process was investigated in this study. Before the advancement, the pharmaceutical wastewater containing lincomycin hydrochloride was pretreated by UASB （upflow anaerobic sludge bed） and a SBR （sequencing batch reactor） process. The residual recalcitrant compounds, measured by gas chromatographymass spectrometry （GC-MS）, mainly consisted of alcohols, phenols, and nitrogenous and sulfur compounds. The experimental results indicated that when the Fenton＇s reaction was conducted at pH=3.0, H2O2CODOcr=0.27, H2O2/Fe^2＋=3：1 and 30 min of reaction time, and the coagulation process operated at a sulfate aluminum concentration of 800 mg/L and pH value of 5.0, the color and COD in the wastewater decreased by 94% and 73%, respectively; with a finale COD concentration of 267 mg/L and color level of 40 units, meeting the secondary standard of GB8978-1996 for industrial wastewater.
文摘Kinetics of homogeneous degradation of Eosin Y (EY), also known as Acid red 87 (CI 45380), are studied, mostly using Fenton’s process, at 30℃ by monitoring its absorbance at 517 nm (λ<sub>max</sub> of EY). This process is one of the advanced oxidation processes (AOPs). Mixture of H<sub>2</sub>O<sub>2</sub> and Fe(II) ion in acetate buffer medium (pH 2.74 - 4.56) generates hydroxyl free radicals (?OH) which attack the dye molecules, resulting in degradation of the dye molecules. Results show that the initial rate of EY degradation decreases with the increasing of solution pH because of removal of kinetically important Fe (iron) species through formation of ferric hydroxide. On the other hand, the rate increases with increasing the concentrations of H<sub>2</sub>O<sub>2</sub>, Fe(II) and EY at low solution pH. The initial rate increases with increasing of concentration of H2O2 and, subsequently remains unaffected with further increase of its concentration at a constant Fe(II) concentration because of the enhanced scavenging environment created by H<sub>2</sub>O<sub>2</sub> at its higher concentration. The initial rate also increases with increasing of concentration of Fe(II) at a constant H<sub>2</sub>O<sub>2</sub> concentration and remains unaffected with its further increase. EY concentration also enhances the initial rate at low pH. However, the initial rate is significantly enhanced by UV light. This is because of formation of additional hydroxyl radicals through excitation of the dye molecules by UV light. During the period of experiment, EY in aqueous solution alone hardly suffered any degradation. Degradation mechanism of EY by the Fenton and photo-Fenton’s processes is also discussed. Statistical analysis was used to validate the experimental results. Low values of the standard deviation for both the initial rate and % degradation indicated the consistency of the experimental data.
