Nano-TiO2 photocatalytic oxidation was used to perform the advanced treatment of biologically treated chemical comprehensive wastewater. The effects of reaction time,nano-TiO2 dosage and initial p H of the wastewater ...Nano-TiO2 photocatalytic oxidation was used to perform the advanced treatment of biologically treated chemical comprehensive wastewater. The effects of reaction time,nano-TiO2 dosage and initial p H of the wastewater on the removal rate of COD were tested. The GC/MS and EEM techniques were used to qualitatively analyze organic compounds in the wastewater before and after treatment. The result showed that after the biologically treated chemical comprehensive wastewater was treated by nano-TiO2 photocatalytic oxidation under the conditions of reaction time 3 h,nano-TiO2 dosage 8 g/L,and pH 8. 0,the effluent COD was 61. 9 mg/L and its removal rate was 63. 8%. Additionally,the species of organic pollutants reduced from 12 to 6. Meanwhile,the content of humic-like and fulvic-like substances dropped dramatically.展开更多
Fe-based metallic glasses (Fe–MGs) are potential candidate catalysts for advanced oxidation processes(AOPs) for recalcitrant organic pollutant degradation. However, industrial wastewater and natural contaminated site...Fe-based metallic glasses (Fe–MGs) are potential candidate catalysts for advanced oxidation processes(AOPs) for recalcitrant organic pollutant degradation. However, industrial wastewater and natural contaminated sites usually contain abundant inorganic ions, like the chloride ion (Cl−), which significantly affectAOPs, but their influence on MG-activated AOPs still remains unclear. Through the study of three commonly used oxidants, hydrogen peroxide (H_(2)O_(2)), peroxydisulfate (PDS), and peroxymonosulfate (PMS), theeffect of Cl− on the FeSiB-catalyzed process of degradation of the typical azo dye Orange Ⅱ was investigated. Evidence indicates that the addition of Cl− resulted in the monotonous inhibition of the degradation process when the H_(2)O_(2)/FeSiB and PDS/FeSiB systems were employed, but promoted effect wasdetected with the PMS/FeSiB system, which is different from the previously observed dual effect of Cl−.It is closely relative with FeSiB induced unique variety of degradation pathways, including radicals, nonradicals (^(1)O_(2)), and direct reduction degradation. Moreover, the presence of Cl− significantly affected thesystems’ absorbable organic halogen content and the amount of Fe leached into the solution. The resultsof this work will provide essential references for Fe-based MG used as AOP catalysts in field applicationsand the development of advanced MGs with excellent adaptability to complex environments.展开更多
2,4-Dinitroanisole(DNAN)is an important component of insensitive munitions that is anticipated to replace 2,4,6-trinitrotoluene(TNT)in munitions formulations.Photocatalyzed hydrogen peroxide(H2O2)oxidation experiments...2,4-Dinitroanisole(DNAN)is an important component of insensitive munitions that is anticipated to replace 2,4,6-trinitrotoluene(TNT)in munitions formulations.Photocatalyzed hydrogen peroxide(H2O2)oxidation experiments and chemical analyses were conducted to study the effect of initial pH and H2O2 dosage on the kinetics of DNAN decomposition and the reaction pathways.The results show that DNAN degradation followed zero-order kinetics when a 250 ppm DNAN solution was treated with ultraviolet(UV)light and 1500–4500 ppm H2O2 in an initial pH range of 4–7.However,when the H2O2 concentration was 750 ppm,DNAN degradation followed pseudo-first-order kinetics.The results indicate that DNAN can easily be oxidized by UV/H2O2 treatment.When the H2O2 dosage was 1500 ppm and the initial pH was 7,DNAN was reduced from 250 ppm to less than 1 ppm in 3 h.However,the total organic carbon(TOC)and total carbon(TC)concentrations were reduced slowly from 100 to less than 70 ppm carbon(C)in 3 h,and decreased to about 5 ppm after 9 h of treatment,suggesting the formation of other organic compounds.Those reaction intermediates were oxidized to carbon dioxide(CO2)at a slower rate than the oxidation of DNAN.CO2 was emitted from the solution because the solution pH decreased rapidly to about 3 during the UV/H2O2 oxidation.Most of the nitrogen in DNAN was converted to nitrate by UV/H2O2 oxidation after 9 h of treatment.The research results indicate that UV/H2O2 oxidation is a promising technique for the treatment of DNAN in wastewater.展开更多
As important emerging contaminants, antibiotics have caused potential hazards to the ecological environment and human health due to their extensive production and consumption. Among various techniques for removing ant...As important emerging contaminants, antibiotics have caused potential hazards to the ecological environment and human health due to their extensive production and consumption. Among various techniques for removing antibiotics from wastewater, H_(2)O_(2)-based advanced oxidation processes(AOPs) have received increasing attention due to their fast reaction rate and strong oxidation capability. Hence this review critically discusses:(i) Recent research progress of AOPs with the addition of H_(2)O_(2) for antibiotics removal through different methods of H_(2)O_(2) activation;(ii) recent advances in AOPs that can in-situ generate and activate H_(2)O_(2) for antibiotics removal;(iii) H_(2)O_(2)-based AOPs as a combination with other techniques for the degradation and mineralization of antibiotics in wastewater. Future perspectives about H_(2)O_(2)-based AOPs are also presented to grasp the future research trend in the area.展开更多
In the electrical discharge plasma process, various chemical and physical processes can participate in the removal of contaminants. In this paper, the chemical and physical processes that occur as a result of the elec...In the electrical discharge plasma process, various chemical and physical processes can participate in the removal of contaminants. In this paper, the chemical and physical processes that occur as a result of the electrical discharge plasma are reviewed, and their possible roles in the degradation of contaminants are discussed. Measurement methods for the quantification of important reactive species and their advantages and shortcomings are presented. Approaches on how to enhance the diffusion of the reactive species in solution are examined. In addition, the formation of typical reactive species in different electrical discharge plasma is compared.展开更多
The presence of sulfonamide antibiotics in aquatic environments has received increasing attention in recent years.Sulfadiazine(SD),a widely used heterocyclic sulfonamide pharmaceutical,has entered into the receiving w...The presence of sulfonamide antibiotics in aquatic environments has received increasing attention in recent years.Sulfadiazine(SD),a widely used heterocyclic sulfonamide pharmaceutical,has entered into the receiving water body.In this paper,gamma rays are used to irradiate samples of sulfadiazine antibiotics-containing wastewater.The results demonstrate that SD can be effectively degraded by irradiation,but the mineralization degree of SD(in terms of TOC) is not as efficient as the SD degradation.The addition of Fe^(2+) can significantly enhance the SD degradation and mineralization through the generation of hydroxyl radical by catalytic decomposition of H_2O_2 from water radiolysis.Ion chromatography analysis indicates that sulfate ions(SO_4^(2-)) and formate(HCOO^-) are the main intermediate products.Gamma irradiation is a promising technology for removing low-concentration antibiotics from water and wastewater.展开更多
The great amount of NH3-N produced in biological hydrolysis process of high concentration urea can inhibit the growth of microorganisms. In allusion to this problem,the Fenton reagent was used to treat high concentrat...The great amount of NH3-N produced in biological hydrolysis process of high concentration urea can inhibit the growth of microorganisms. In allusion to this problem,the Fenton reagent was used to treat high concentration urea wastewater. And the optimum conditions of this experiment were employed as follows: Fe(Ⅱ)-H2O2mole ratio was 1/3.53,H2O2 was 4 mL (corresponding to 35.30 mmol),pH was 3.0-3.5. Then the experiment shows that the urea concentration decreases from 500 mg/L to less than 2 mg/L,or is even not detected; under the same dose of H2O2,repetitious addition does better than one-off addition; the reaction time within one minute or to be prolonged has little influence on removal effect. The results verify feasibility of this method.展开更多
文摘Nano-TiO2 photocatalytic oxidation was used to perform the advanced treatment of biologically treated chemical comprehensive wastewater. The effects of reaction time,nano-TiO2 dosage and initial p H of the wastewater on the removal rate of COD were tested. The GC/MS and EEM techniques were used to qualitatively analyze organic compounds in the wastewater before and after treatment. The result showed that after the biologically treated chemical comprehensive wastewater was treated by nano-TiO2 photocatalytic oxidation under the conditions of reaction time 3 h,nano-TiO2 dosage 8 g/L,and pH 8. 0,the effluent COD was 61. 9 mg/L and its removal rate was 63. 8%. Additionally,the species of organic pollutants reduced from 12 to 6. Meanwhile,the content of humic-like and fulvic-like substances dropped dramatically.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.52101195,51871120)the Natural Science Foundation of Jiangsu Province(Nos.BK20190480,BK20200019)+1 种基金the Fundamental Research Funds for the Central Universities(Nos.30920021156,30920010004)the GuangdongHong Kong-Macao Joint Laboratory for Neutron Scattering Science and Technology。
文摘Fe-based metallic glasses (Fe–MGs) are potential candidate catalysts for advanced oxidation processes(AOPs) for recalcitrant organic pollutant degradation. However, industrial wastewater and natural contaminated sites usually contain abundant inorganic ions, like the chloride ion (Cl−), which significantly affectAOPs, but their influence on MG-activated AOPs still remains unclear. Through the study of three commonly used oxidants, hydrogen peroxide (H_(2)O_(2)), peroxydisulfate (PDS), and peroxymonosulfate (PMS), theeffect of Cl− on the FeSiB-catalyzed process of degradation of the typical azo dye Orange Ⅱ was investigated. Evidence indicates that the addition of Cl− resulted in the monotonous inhibition of the degradation process when the H_(2)O_(2)/FeSiB and PDS/FeSiB systems were employed, but promoted effect wasdetected with the PMS/FeSiB system, which is different from the previously observed dual effect of Cl−.It is closely relative with FeSiB induced unique variety of degradation pathways, including radicals, nonradicals (^(1)O_(2)), and direct reduction degradation. Moreover, the presence of Cl− significantly affected thesystems’ absorbable organic halogen content and the amount of Fe leached into the solution. The resultsof this work will provide essential references for Fe-based MG used as AOP catalysts in field applicationsand the development of advanced MGs with excellent adaptability to complex environments.
文摘2,4-Dinitroanisole(DNAN)is an important component of insensitive munitions that is anticipated to replace 2,4,6-trinitrotoluene(TNT)in munitions formulations.Photocatalyzed hydrogen peroxide(H2O2)oxidation experiments and chemical analyses were conducted to study the effect of initial pH and H2O2 dosage on the kinetics of DNAN decomposition and the reaction pathways.The results show that DNAN degradation followed zero-order kinetics when a 250 ppm DNAN solution was treated with ultraviolet(UV)light and 1500–4500 ppm H2O2 in an initial pH range of 4–7.However,when the H2O2 concentration was 750 ppm,DNAN degradation followed pseudo-first-order kinetics.The results indicate that DNAN can easily be oxidized by UV/H2O2 treatment.When the H2O2 dosage was 1500 ppm and the initial pH was 7,DNAN was reduced from 250 ppm to less than 1 ppm in 3 h.However,the total organic carbon(TOC)and total carbon(TC)concentrations were reduced slowly from 100 to less than 70 ppm carbon(C)in 3 h,and decreased to about 5 ppm after 9 h of treatment,suggesting the formation of other organic compounds.Those reaction intermediates were oxidized to carbon dioxide(CO2)at a slower rate than the oxidation of DNAN.CO2 was emitted from the solution because the solution pH decreased rapidly to about 3 during the UV/H2O2 oxidation.Most of the nitrogen in DNAN was converted to nitrate by UV/H2O2 oxidation after 9 h of treatment.The research results indicate that UV/H2O2 oxidation is a promising technique for the treatment of DNAN in wastewater.
基金financially supported by National Natural Science Foundation of China(Nos.21976096,52170085 and 21773129)Tianjin Development Program for Innovation and Entrepreneurship+2 种基金Key Project of Natural Science Foundation of Tianjin(No.21JCZDJC00320)Tianjin Post-graduate Students Research and Innovation Project(No.2021YJSB013)Fundamental Research Funds for the Central Universities,Nankai University。
文摘As important emerging contaminants, antibiotics have caused potential hazards to the ecological environment and human health due to their extensive production and consumption. Among various techniques for removing antibiotics from wastewater, H_(2)O_(2)-based advanced oxidation processes(AOPs) have received increasing attention due to their fast reaction rate and strong oxidation capability. Hence this review critically discusses:(i) Recent research progress of AOPs with the addition of H_(2)O_(2) for antibiotics removal through different methods of H_(2)O_(2) activation;(ii) recent advances in AOPs that can in-situ generate and activate H_(2)O_(2) for antibiotics removal;(iii) H_(2)O_(2)-based AOPs as a combination with other techniques for the degradation and mineralization of antibiotics in wastewater. Future perspectives about H_(2)O_(2)-based AOPs are also presented to grasp the future research trend in the area.
基金funded by National Natural Science Foundation of China (Nos. 51608448 and 21737003)Young Talent Cultivation Scheme Funding of Northwest A&F University (No. Z109021802)the Fundamental Research Funds for the Central Universities (No. Z109021617) for their financial support in this research
文摘In the electrical discharge plasma process, various chemical and physical processes can participate in the removal of contaminants. In this paper, the chemical and physical processes that occur as a result of the electrical discharge plasma are reviewed, and their possible roles in the degradation of contaminants are discussed. Measurement methods for the quantification of important reactive species and their advantages and shortcomings are presented. Approaches on how to enhance the diffusion of the reactive species in solution are examined. In addition, the formation of typical reactive species in different electrical discharge plasma is compared.
基金supported by the National Natural Science Foundation of China(No.51338005)
文摘The presence of sulfonamide antibiotics in aquatic environments has received increasing attention in recent years.Sulfadiazine(SD),a widely used heterocyclic sulfonamide pharmaceutical,has entered into the receiving water body.In this paper,gamma rays are used to irradiate samples of sulfadiazine antibiotics-containing wastewater.The results demonstrate that SD can be effectively degraded by irradiation,but the mineralization degree of SD(in terms of TOC) is not as efficient as the SD degradation.The addition of Fe^(2+) can significantly enhance the SD degradation and mineralization through the generation of hydroxyl radical by catalytic decomposition of H_2O_2 from water radiolysis.Ion chromatography analysis indicates that sulfate ions(SO_4^(2-)) and formate(HCOO^-) are the main intermediate products.Gamma irradiation is a promising technology for removing low-concentration antibiotics from water and wastewater.
文摘The great amount of NH3-N produced in biological hydrolysis process of high concentration urea can inhibit the growth of microorganisms. In allusion to this problem,the Fenton reagent was used to treat high concentration urea wastewater. And the optimum conditions of this experiment were employed as follows: Fe(Ⅱ)-H2O2mole ratio was 1/3.53,H2O2 was 4 mL (corresponding to 35.30 mmol),pH was 3.0-3.5. Then the experiment shows that the urea concentration decreases from 500 mg/L to less than 2 mg/L,or is even not detected; under the same dose of H2O2,repetitious addition does better than one-off addition; the reaction time within one minute or to be prolonged has little influence on removal effect. The results verify feasibility of this method.
