Polyacrylamide-urea-sulfanilamide(PUS) was prepared as a novel heavy metal ions chelator and successfully used to simultaneously remove heavy metals from wastewater effluents.The effects of reaction parameters(sodi...Polyacrylamide-urea-sulfanilamide(PUS) was prepared as a novel heavy metal ions chelator and successfully used to simultaneously remove heavy metals from wastewater effluents.The effects of reaction parameters(sodium hydroxide,material ratio,temprature and contact time) were monitored to specify the best synthesis conditions.PUS was chemically characterized by means of infrared spectroscopy(FTIR) and ultraviolet-visible(UV-Vis).The simultaneous chelation performance of PUS towards selected heavy metals ions,Ni2+,Cu2+,Pb2+,Zn2+,Cd2+ was discussed,showing that Ni2+,Cu2+,Pb2+,Zn2+ could be better chelated.It is indicated that the synthesized PUS is a potential remediation material when used for the treatment of wastewater containing metal ions.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
The removal efficiencies of heavy metals(As, Cr, Cu, Ni, Pb and Zn) were investigated in the 17 operating municipal wastewater treatment plants(WWTPs) and compared with those in four main activated sludge processes. S...The removal efficiencies of heavy metals(As, Cr, Cu, Ni, Pb and Zn) were investigated in the 17 operating municipal wastewater treatment plants(WWTPs) and compared with those in four main activated sludge processes. Significant differences of heavy metal removal efficiencies were observed among four activated sludge processes. The removal efficiency for As(75.5%) in the oxidation ditch(OD) process is significantly higher than that in the conventional activated sludge(CAS) process(38.6%) or sequencing batch reactor(SBR) process(51.4%). The mean removal efficiencies for Cu and Ni in the OD process are 90.5% and 46.7%, respectively, while low mean removal efficiencies are observed for Cu(69.9%) and Ni(16.5%), respectively, in the SBR process. The removal efficiencies for Cu and Ni in the OD process are significantly higher than those in the anaerobic-anoxic-oxic(A2-O) process. These results highlight the differences of removal efficiencies for heavy metals in different processes and should be considered when selecting a wastewater treatment process.展开更多
Functional nanofibrous membranes fabricated by electrospinning technology have attracted much attention in the removal of heavy metal ions from contaminated wastewater.The high specific surface area,high porosity and ...Functional nanofibrous membranes fabricated by electrospinning technology have attracted much attention in the removal of heavy metal ions from contaminated wastewater.The high specific surface area,high porosity and ease of functionality create an enhanced throughput and high adsorption capacity of the nanofibrous membrane.However,the relatively poor mechanical properties of the membrane with a non-woven nanofibrous structure are one of the major concerns,which can limit the applications in wastewater treatment.Different strategies and methodologies were explored to address the problems and were reviewed in this work,highlighting the possibilities of overcoming the poor mechanical properties of the nanofibrous membrane and to ensure the recyclability and reusability of the membrane during the adsorption process.展开更多
Rectifier diode production wastewater that contains acid,alkali and heavy metal ions in a company was treated by using neutralization/coagulation sedimentation method.Firstly,pH of wastewater was adjusted via neutrali...Rectifier diode production wastewater that contains acid,alkali and heavy metal ions in a company was treated by using neutralization/coagulation sedimentation method.Firstly,pH of wastewater was adjusted via neutralization reaction,and then heavy metal ions(Cu^(2+),Cr^(2+)and Pb^(2+))were removed by adding coagulant PAC and flocculant PAM.Different acid-alkali neutralization reactions were conducted under the process condition to analyze and compare their neutralization effects.The results showed that removal rates of heavy metal ions were high after coagulation test:Cu^(2+),Pb^(2+)and Cr^(2+)contents dropped from 13.230,0.032,and 1.720mg/L to 0.3,0.001,and 0.24mg/L;besides,total iron,total manganese and turbidity all had very good removal effects.展开更多
基金Funded by the Cooperative Project of Yulin City,Shaanxi Province,201
文摘Polyacrylamide-urea-sulfanilamide(PUS) was prepared as a novel heavy metal ions chelator and successfully used to simultaneously remove heavy metals from wastewater effluents.The effects of reaction parameters(sodium hydroxide,material ratio,temprature and contact time) were monitored to specify the best synthesis conditions.PUS was chemically characterized by means of infrared spectroscopy(FTIR) and ultraviolet-visible(UV-Vis).The simultaneous chelation performance of PUS towards selected heavy metals ions,Ni2+,Cu2+,Pb2+,Zn2+,Cd2+ was discussed,showing that Ni2+,Cu2+,Pb2+,Zn2+ could be better chelated.It is indicated that the synthesized PUS is a potential remediation material when used for the treatment of wastewater containing metal ions.
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.
基金Project(2012AA06A202)supported by Hi-tech Research and Development Project of China
文摘The removal efficiencies of heavy metals(As, Cr, Cu, Ni, Pb and Zn) were investigated in the 17 operating municipal wastewater treatment plants(WWTPs) and compared with those in four main activated sludge processes. Significant differences of heavy metal removal efficiencies were observed among four activated sludge processes. The removal efficiency for As(75.5%) in the oxidation ditch(OD) process is significantly higher than that in the conventional activated sludge(CAS) process(38.6%) or sequencing batch reactor(SBR) process(51.4%). The mean removal efficiencies for Cu and Ni in the OD process are 90.5% and 46.7%, respectively, while low mean removal efficiencies are observed for Cu(69.9%) and Ni(16.5%), respectively, in the SBR process. The removal efficiencies for Cu and Ni in the OD process are significantly higher than those in the anaerobic-anoxic-oxic(A2-O) process. These results highlight the differences of removal efficiencies for heavy metals in different processes and should be considered when selecting a wastewater treatment process.
基金This work was supported by the National Natural Science Foundation of China(No.51673011)the Project of the State Key Laboratory of Organic-Inorganic Composites at Beijing University of Chemical Technology,China(No.oic-202001002).
文摘Functional nanofibrous membranes fabricated by electrospinning technology have attracted much attention in the removal of heavy metal ions from contaminated wastewater.The high specific surface area,high porosity and ease of functionality create an enhanced throughput and high adsorption capacity of the nanofibrous membrane.However,the relatively poor mechanical properties of the membrane with a non-woven nanofibrous structure are one of the major concerns,which can limit the applications in wastewater treatment.Different strategies and methodologies were explored to address the problems and were reviewed in this work,highlighting the possibilities of overcoming the poor mechanical properties of the nanofibrous membrane and to ensure the recyclability and reusability of the membrane during the adsorption process.
文摘Rectifier diode production wastewater that contains acid,alkali and heavy metal ions in a company was treated by using neutralization/coagulation sedimentation method.Firstly,pH of wastewater was adjusted via neutralization reaction,and then heavy metal ions(Cu^(2+),Cr^(2+)and Pb^(2+))were removed by adding coagulant PAC and flocculant PAM.Different acid-alkali neutralization reactions were conducted under the process condition to analyze and compare their neutralization effects.The results showed that removal rates of heavy metal ions were high after coagulation test:Cu^(2+),Pb^(2+)and Cr^(2+)contents dropped from 13.230,0.032,and 1.720mg/L to 0.3,0.001,and 0.24mg/L;besides,total iron,total manganese and turbidity all had very good removal effects.