A simple and efficient sonochemical method was developed for the degradation of organic matter and ammonia nitrogen in azodicarbonamide wastewater.The effects of initial pH,ultrasound format and peripheral water level...A simple and efficient sonochemical method was developed for the degradation of organic matter and ammonia nitrogen in azodicarbonamide wastewater.The effects of initial pH,ultrasound format and peripheral water level on the sonolysis of hydrazine,urea,COD and ammonia nitrogen were investigated.It is found that the initial pH has a significant influence on the degradation of hydrazine and ammonia nitrogen,whereas this impact to urea is relatively small.It also shows that a noticeable enhancement of ammonia nitrogen removal could be achieved in a proper intermittent ultrasound operation mode,i.e.,1/1 min on/off mode.The height difference between the periph-eral water level and the inner water level of the flask affects the efficiency of ultrasonic treatment as well.展开更多
The serious limitations of available technologies for decontamination of wastewater have compelled researchers to search for alternative solutions. Catalytic treatment with hydrogen peroxide, which appears to be one o...The serious limitations of available technologies for decontamination of wastewater have compelled researchers to search for alternative solutions. Catalytic treatment with hydrogen peroxide, which appears to be one of the most efficient treatment systems, is able to degrade various organics with the help of powerful ·OH radicals. This review focuses on recent progress in the use of bicarbonate activated hydrogen peroxide for wastewater treatment. The introduction of bicarbonate to pollutant treatment has led to appreciable improvements, not only in process efficiency, but also in process stability. This review describes in detail the applications of this process in homogeneous and heterogeneous systems. The enhanced degradation, limited or lack of leaching during heterogeneous degradation, and prolonged catalysts stability during degradation are salient features of this system. This review provides readers with new knowledge regarding bicarbonate, including the fact that it does not always harm pollutant degradation, and can significantly benefit degradation under some conditions.展开更多
Oxidation of sulfide in aqueous solution by hydrogen peroxide was investigated in the presence of hydrated ferric oxide catalyst. The ferric oxide catalyst was synthesized by sol gel technique from ferric chloride and...Oxidation of sulfide in aqueous solution by hydrogen peroxide was investigated in the presence of hydrated ferric oxide catalyst. The ferric oxide catalyst was synthesized by sol gel technique from ferric chloride and ammonia. The synthesized catalyst was characterized by Fourier transform infrared spectroscopy, X-Ray diffraction analysis, scanning electrom microscope and energy dispersive X-ray analysis. The catalyst was quite effective in oxidizing the sulfide by hydrogen peroxide. The effects of sulfide concentration, catalyst loading, H2O2 dosing and temperature on the kinetics of sulfide oxidation were investigated. Kinetic equations and activation energies for the catalytic oxidation reaction were calculated based on the experimental results.展开更多
The zero valent iron/granular active carbon(ZVI/GAC) micro-electrolysis enhanced by ultrasound(US) coupled with hydrogen peroxide(H_2O_2) was investigated for the deep degradation of nitrobenzene-containing wastewater...The zero valent iron/granular active carbon(ZVI/GAC) micro-electrolysis enhanced by ultrasound(US) coupled with hydrogen peroxide(H_2O_2) was investigated for the deep degradation of nitrobenzene-containing wastewater. The results of scanning electron microscopy-energy dispersive X-rays analysis(SEM-EDS) demonstrated that continuously accelerated regeneration of ZVI and GAC in situ by US could improve the process for converting nitrobenzene(NB) to aniline(AN). H_2O_2 was decomposed catalytically by the byproduct Fe^(2+) ions generated in the micro-electrolysis process to hydroxyl radicals and the organic pollutants in the wastewater were finally mineralized to CO2 and H2O. Effects of the ZVI dosage, the ZVI/GAC mass ratio, the initial pH value and the H_2O_2 dosage on the efficiency for degradation of NB were studied in these experiments. The optimal operating conditions covered a ZVI dosage of 15 g/L, a ZVI/GAC mass ratio of 1:2,an initial pH value of 3 and a H_2O_2 dosage of 4 mL. In this case, the NB removal efficiency reached 97.72% and the total organic carbon(TOC) removal efficiency reached 73.42% at a NB concentration of 300 mg/L. The reduction of NB by USZVI/GAC followed the pseudo-first-order kinetics model, and the pseudo-first-order rate constants were given at different initial pH values. The reaction intermediates such as AN, benzoquinonimine, p-benzoquinone, p-nitrophenol and other organic acids were detected and a probable pathway for NB degradation has been proposed.展开更多
The paper presents results of phenol oxidized under the conditions of high temperature created during collapse of cavitation bubbles.The degradation efficiency has been greatly improved by using cavitation water jets ...The paper presents results of phenol oxidized under the conditions of high temperature created during collapse of cavitation bubbles.The degradation efficiency has been greatly improved by using cavitation water jets combined with H2O2 as demonstrated in laboratory tests.Various factors affecting phenol removal ratio were ex-amined and the degradation mechanism was revealed by high performance liquid chromatography(HPLC).The re-sults showed that 99.85% of phenol was mineralized when phenol concentration was 100 mg·L-1 with pH value of 3.0,H2O2 concentration of 300 mg·L-1,confining pressure of 0.5 MPa,and pumping pressure of 20 MPa.The in-termediate products after phenol oxidation were composed of catechol,hydroquinone and p-benzoquinone.Finally,phenol was degraded into maleic acid and acetic acid.Furthermore,a dynamic model of phenol oxidation via cavi-tation water jets combined with H2O2 has been developed.展开更多
This research was focused on the investigation of the efficacy of advanced oxidation processes （Fenton, ozonation and UV/H2O2） for decolorization of reactive azo dye （Blue CL-BR） using bleach wastewater as possibl...This research was focused on the investigation of the efficacy of advanced oxidation processes （Fenton, ozonation and UV/H2O2） for decolorization of reactive azo dye （Blue CL-BR） using bleach wastewater as possible source of H2O2. All the experiments were performed on the laboratory scale set-up. The results showed that colour removal efficiencies by UV or bleach （H2O2） alone were not so efficient. Fenton process with bleach wastewater was found to be the most effective at process conditions such as pH of 3 and HEO2/Fe^2＋ ratio of 24：1, resulting in 64% colour removal. Almost complete colour removal, i.e., 99% and 95% were achieved by UV//H2O2 and UV/bleach wastewater in 30 and 60 min, respectively. Ozonation proved an efficient method for decolorization of Blue CL-BR dye at alkaline pH. It was possible to achieve 98% colour removal with 30 min of ozonation at pH 9. The colour removal of dye was found to follow first order kinetics.展开更多
[Objectives]To treat pig farm wastewater and solve the problem of pollution caused by it to surface water or groundwater.[Methods]Fe and Zn/biochar(AC)was prepared by dipping method using pig manure-derived biochar as...[Objectives]To treat pig farm wastewater and solve the problem of pollution caused by it to surface water or groundwater.[Methods]Fe and Zn/biochar(AC)was prepared by dipping method using pig manure-derived biochar as carrier.The preparation conditions were investigated,and the screened metal-loaded biochar was characterized.Pig farm waste water was treated with metal-loaded biochar-H2O2 catalytic oxidation method.[Results]At the COD concentration of 2904 mg/L,0.02 g Zn/AC and 0.005 mL H2O2 showed the highest COD removal rate(qe)from pig breeding wastewater under conditions of reaction time of 8 h,pH value of 7 and temperature of 55℃,reaching 70.98%.[Conclusions]Fe or Zn-loaded biochar made from pig manure-derived activated carbon has a certain catalytic capacity for the actual oxidation treatment of pig farm wastewater.The activity of Zn/AC was higher,and its COD removal rate from pig farm wastewater was also higher.展开更多
Azithromycin(AZT)is a broad-spectrum antibiotic from the group of macrolides that acts against several Gram-positive and Gram-negative bacteria,which has promoted its use in the treatment of different respiratory and ...Azithromycin(AZT)is a broad-spectrum antibiotic from the group of macrolides that acts against several Gram-positive and Gram-negative bacteria,which has promoted its use in the treatment of different respiratory and sexually transmitted diseases.However,its presence in environmental matrices and in the effluents of conventional wastewater treatment plants has been evidenced in recent years,which reflects the need to develop new treatment alternatives that allow its total removal and minimize the eventual adverse effects,selection of resistant bacterial strains,associated with its presence in water bodies.Simulated sunlight radiation and H2O2 were used to remove AZT from water assessing the effects of operational parameters like the solution initial pH and the peroxide concentration.Results indicate that hydroxyl free radical is the main responsible for pollutant removal but acidic solution conditions and larger H2O2 doses negatively affect OHgeneration under the evaluated experimental conditions.Pollutant removal was almost complete after 120 min of photo-treatment.In addition,reduction of the organic carbon content in the treated samples was^50.0%;and a significant increase of nitrates concentration in solution was evidenced.展开更多
The electro-peroxone technology,a novel type of advanced oxidation technology,is widely used in wastewater treatment.Herein,this paper reviews the advantages and problems of the electro-peroxone technology compared wi...The electro-peroxone technology,a novel type of advanced oxidation technology,is widely used in wastewater treatment.Herein,this paper reviews the advantages and problems of the electro-peroxone technology compared with electrochemical oxidation technology,ozonation technology,and traditional peroxone technology.Due to the high kinetics of pollutant degradation,the electro-peroxone process can reduce the reaction time and energy consumption of pollutant treatment in wastewater.The electroperoxone technology can promote pollutant degradation and mineralization,which shows obvious synergistic effects of electrochemical oxidation and ozonation for wastewater treatment.Most importantly,the research mechanism of the electro-peroxone technology is systematically introduced from two aspects of cathode reaction and bulk reaction.The influence of experimental parameters on the wastewater treatment effect is also discussed.Finally,the potential applications and future research directions of the electro-peroxone technology in the wastewater field are proposed.The electro-peroxone process can offer a highly efficient and energy saving water treatment method to improve the performance of existing ozonation and electrochemical systems and has therefore become a promising electrochemical advanced oxidation process for wastewater treatment.展开更多
对汽提后百草枯废水与双氧水连续氧化氰根的反应进行研究,确认了使用27.5%含量双氧水与百草枯废水混合配制,其中双氧水与废水比例为8.3%,控制反应器内温度55℃反应18 h 45 min后,汽提后百草枯废水破氰效果基本达到峰值,废水中氰根可有25...对汽提后百草枯废水与双氧水连续氧化氰根的反应进行研究,确认了使用27.5%含量双氧水与百草枯废水混合配制,其中双氧水与废水比例为8.3%,控制反应器内温度55℃反应18 h 45 min后,汽提后百草枯废水破氰效果基本达到峰值,废水中氰根可有2500 mg/kg左右降至100 mg/kg以下,同时出水为黄色透明溶液,大幅降低了焦油、有机杂质的含量,废水中氰根降低明显,色度明显好转,处理后得到的铵盐无需后续处理既可直接利用。同时通过流态模拟分析混合溶液在塔式反应器内各点位流速状态及反应情况,物料有反应塔下口进反应塔测上口出时,反应塔内各点位流速均匀,除进出口少量点位流速较大外,进入体系后,流速基本稳定且较低,该条件下反应效果最佳。展开更多
基金Supported by the National Natural Science Foundation of China (21121064,20990224)National Science and Technology Ministry of China (2008BAE64B02)
文摘A simple and efficient sonochemical method was developed for the degradation of organic matter and ammonia nitrogen in azodicarbonamide wastewater.The effects of initial pH,ultrasound format and peripheral water level on the sonolysis of hydrazine,urea,COD and ammonia nitrogen were investigated.It is found that the initial pH has a significant influence on the degradation of hydrazine and ammonia nitrogen,whereas this impact to urea is relatively small.It also shows that a noticeable enhancement of ammonia nitrogen removal could be achieved in a proper intermittent ultrasound operation mode,i.e.,1/1 min on/off mode.The height difference between the periph-eral water level and the inner water level of the flask affects the efficiency of ultrasonic treatment as well.
基金supported by the National Natural Science Foundation of China(21273086)~~
文摘The serious limitations of available technologies for decontamination of wastewater have compelled researchers to search for alternative solutions. Catalytic treatment with hydrogen peroxide, which appears to be one of the most efficient treatment systems, is able to degrade various organics with the help of powerful ·OH radicals. This review focuses on recent progress in the use of bicarbonate activated hydrogen peroxide for wastewater treatment. The introduction of bicarbonate to pollutant treatment has led to appreciable improvements, not only in process efficiency, but also in process stability. This review describes in detail the applications of this process in homogeneous and heterogeneous systems. The enhanced degradation, limited or lack of leaching during heterogeneous degradation, and prolonged catalysts stability during degradation are salient features of this system. This review provides readers with new knowledge regarding bicarbonate, including the fact that it does not always harm pollutant degradation, and can significantly benefit degradation under some conditions.
文摘Oxidation of sulfide in aqueous solution by hydrogen peroxide was investigated in the presence of hydrated ferric oxide catalyst. The ferric oxide catalyst was synthesized by sol gel technique from ferric chloride and ammonia. The synthesized catalyst was characterized by Fourier transform infrared spectroscopy, X-Ray diffraction analysis, scanning electrom microscope and energy dispersive X-ray analysis. The catalyst was quite effective in oxidizing the sulfide by hydrogen peroxide. The effects of sulfide concentration, catalyst loading, H2O2 dosing and temperature on the kinetics of sulfide oxidation were investigated. Kinetic equations and activation energies for the catalytic oxidation reaction were calculated based on the experimental results.
基金supported by the Natural Science Foundation of China (U1610106)the Excellent Youth Science and Technology Foundation of Province Shanxi of China (2014021007)+1 种基金the Specialized Research Fund for Sanjin Scholars Pragram of Shanxi Prouince (201707)the North University of China Fund for Distinguished Young Scholars (201701)
文摘The zero valent iron/granular active carbon(ZVI/GAC) micro-electrolysis enhanced by ultrasound(US) coupled with hydrogen peroxide(H_2O_2) was investigated for the deep degradation of nitrobenzene-containing wastewater. The results of scanning electron microscopy-energy dispersive X-rays analysis(SEM-EDS) demonstrated that continuously accelerated regeneration of ZVI and GAC in situ by US could improve the process for converting nitrobenzene(NB) to aniline(AN). H_2O_2 was decomposed catalytically by the byproduct Fe^(2+) ions generated in the micro-electrolysis process to hydroxyl radicals and the organic pollutants in the wastewater were finally mineralized to CO2 and H2O. Effects of the ZVI dosage, the ZVI/GAC mass ratio, the initial pH value and the H_2O_2 dosage on the efficiency for degradation of NB were studied in these experiments. The optimal operating conditions covered a ZVI dosage of 15 g/L, a ZVI/GAC mass ratio of 1:2,an initial pH value of 3 and a H_2O_2 dosage of 4 mL. In this case, the NB removal efficiency reached 97.72% and the total organic carbon(TOC) removal efficiency reached 73.42% at a NB concentration of 300 mg/L. The reduction of NB by USZVI/GAC followed the pseudo-first-order kinetics model, and the pseudo-first-order rate constants were given at different initial pH values. The reaction intermediates such as AN, benzoquinonimine, p-benzoquinone, p-nitrophenol and other organic acids were detected and a probable pathway for NB degradation has been proposed.
基金Supported by the National Natural Science Foundation of China (50921063,51104191)the Natural Science Foundationof Chongqing (2009BA6047)
文摘The paper presents results of phenol oxidized under the conditions of high temperature created during collapse of cavitation bubbles.The degradation efficiency has been greatly improved by using cavitation water jets combined with H2O2 as demonstrated in laboratory tests.Various factors affecting phenol removal ratio were ex-amined and the degradation mechanism was revealed by high performance liquid chromatography(HPLC).The re-sults showed that 99.85% of phenol was mineralized when phenol concentration was 100 mg·L-1 with pH value of 3.0,H2O2 concentration of 300 mg·L-1,confining pressure of 0.5 MPa,and pumping pressure of 20 MPa.The in-termediate products after phenol oxidation were composed of catechol,hydroquinone and p-benzoquinone.Finally,phenol was degraded into maleic acid and acetic acid.Furthermore,a dynamic model of phenol oxidation via cavi-tation water jets combined with H2O2 has been developed.
文摘This research was focused on the investigation of the efficacy of advanced oxidation processes （Fenton, ozonation and UV/H2O2） for decolorization of reactive azo dye （Blue CL-BR） using bleach wastewater as possible source of H2O2. All the experiments were performed on the laboratory scale set-up. The results showed that colour removal efficiencies by UV or bleach （H2O2） alone were not so efficient. Fenton process with bleach wastewater was found to be the most effective at process conditions such as pH of 3 and HEO2/Fe^2＋ ratio of 24：1, resulting in 64% colour removal. Almost complete colour removal, i.e., 99% and 95% were achieved by UV//H2O2 and UV/bleach wastewater in 30 and 60 min, respectively. Ozonation proved an efficient method for decolorization of Blue CL-BR dye at alkaline pH. It was possible to achieve 98% colour removal with 30 min of ozonation at pH 9. The colour removal of dye was found to follow first order kinetics.
基金Scientific and Technological Innovation Project of Jingjiang City,Jiangsu Province(HDCXJ6001).
文摘[Objectives]To treat pig farm wastewater and solve the problem of pollution caused by it to surface water or groundwater.[Methods]Fe and Zn/biochar(AC)was prepared by dipping method using pig manure-derived biochar as carrier.The preparation conditions were investigated,and the screened metal-loaded biochar was characterized.Pig farm waste water was treated with metal-loaded biochar-H2O2 catalytic oxidation method.[Results]At the COD concentration of 2904 mg/L,0.02 g Zn/AC and 0.005 mL H2O2 showed the highest COD removal rate(qe)from pig breeding wastewater under conditions of reaction time of 8 h,pH value of 7 and temperature of 55℃,reaching 70.98%.[Conclusions]Fe or Zn-loaded biochar made from pig manure-derived activated carbon has a certain catalytic capacity for the actual oxidation treatment of pig farm wastewater.The activity of Zn/AC was higher,and its COD removal rate from pig farm wastewater was also higher.
文摘Azithromycin(AZT)is a broad-spectrum antibiotic from the group of macrolides that acts against several Gram-positive and Gram-negative bacteria,which has promoted its use in the treatment of different respiratory and sexually transmitted diseases.However,its presence in environmental matrices and in the effluents of conventional wastewater treatment plants has been evidenced in recent years,which reflects the need to develop new treatment alternatives that allow its total removal and minimize the eventual adverse effects,selection of resistant bacterial strains,associated with its presence in water bodies.Simulated sunlight radiation and H2O2 were used to remove AZT from water assessing the effects of operational parameters like the solution initial pH and the peroxide concentration.Results indicate that hydroxyl free radical is the main responsible for pollutant removal but acidic solution conditions and larger H2O2 doses negatively affect OHgeneration under the evaluated experimental conditions.Pollutant removal was almost complete after 120 min of photo-treatment.In addition,reduction of the organic carbon content in the treated samples was^50.0%;and a significant increase of nitrates concentration in solution was evidenced.
基金the financial support provided by the National Natural Science Foundation of China(No.21306175)the Zhejiang Provincial Natural Science Foundation of China(No.LGJ18E080001)+1 种基金the Project of Science and Technology Department of Jiashan(Nos.2020D02 and 2022A23)Zhejiang Province(No.2015C03017)。
文摘The electro-peroxone technology,a novel type of advanced oxidation technology,is widely used in wastewater treatment.Herein,this paper reviews the advantages and problems of the electro-peroxone technology compared with electrochemical oxidation technology,ozonation technology,and traditional peroxone technology.Due to the high kinetics of pollutant degradation,the electro-peroxone process can reduce the reaction time and energy consumption of pollutant treatment in wastewater.The electroperoxone technology can promote pollutant degradation and mineralization,which shows obvious synergistic effects of electrochemical oxidation and ozonation for wastewater treatment.Most importantly,the research mechanism of the electro-peroxone technology is systematically introduced from two aspects of cathode reaction and bulk reaction.The influence of experimental parameters on the wastewater treatment effect is also discussed.Finally,the potential applications and future research directions of the electro-peroxone technology in the wastewater field are proposed.The electro-peroxone process can offer a highly efficient and energy saving water treatment method to improve the performance of existing ozonation and electrochemical systems and has therefore become a promising electrochemical advanced oxidation process for wastewater treatment.
