In this study,to efficiently remove Pb(Ⅱ) from aqueous environments,a novel L-serine-modified polyethylene/polypropylene nonwoven fabric sorbent(NWF-serine)was fabricated through the radiation grafting of glycidyl me...In this study,to efficiently remove Pb(Ⅱ) from aqueous environments,a novel L-serine-modified polyethylene/polypropylene nonwoven fabric sorbent(NWF-serine)was fabricated through the radiation grafting of glycidyl methacrylate and subsequent L-serine modification.The effect of the absorbed dose was investigated in the range of 5–50 kGy.NWF-serine was characterized by Fourier transform infrared spectroscopy,thermogravimetric analysis,and scanning electron microscopy.Batch adsorption tests were conducted to investigate the influences of pH,adsorption time,temperature,initial concentration,and sorbent dosage on the Pb(Ⅱ) adsorption performance of NWF-serine.The results indicated that Pb(Ⅱ) adsorption onto NWF-serine was an endothermic process,following the pseudo-second-order kinetic model and Langmuir isotherm model.The saturated adsorption capacity was 198.1 mg/g.NWF-serine exhibited Pb(Ⅱ) removal rates of 99.8% for aqueous solutions with initial concentrations of 100 mg/L and 82.1% for landfill leachate containing competitive metal ions such as Cd,Cu,Ni,Mn,and Zn.Furthermore,NWF-serine maintained 86% of its Pb(Ⅱ) uptake after five use cycles.The coordination of the carboxyl and amino groups with Pb(Ⅱ) was confirmed using X-ray photoelectron spectroscopy and extended X-ray absorption fine structure analysis.展开更多
High concentrations of copper ions(Cu(Ⅱ)) in water will pose health risks to humans and the ecological environment. Therefore, this study aims to utilize ultrasonic-cured modified municipal solid waste incineration(M...High concentrations of copper ions(Cu(Ⅱ)) in water will pose health risks to humans and the ecological environment. Therefore, this study aims to utilize ultrasonic-cured modified municipal solid waste incineration(MSWI) fly ash for Cu(Ⅱ) adsorption to achieve the purpose of “treating waste by waste.” The effects of p H, adsorption time, initial concentration, and temperature on the modified MSWI fly ash’s adsorption efficiency were systematically studied in this article. The adsorption performance of the modified MSWI fly ash can be enhanced by the ultrasonic modification. At pH = 2, 3 and 4, the adsorption capacity of the modified MSWI fly ash for Cu(Ⅱ) increased by 2.7, 1.9 and 1.2 times, respectively. Furthermore, it was suggested that the adsorption process of the modified MSWI fly ash can be better simulated by the pseudo-second-order kinetic model, with a maximum adsorption capacity calculated by the Langmuir model of 24.196 mg.g-1. Additionally, the adsorption process is spontaneous,endothermic, and chemisorption-dominated from the thermodynamic studies(ΔH and ΔS > 0, ΔG < 0).Finally, the enhanced adsorption performance of the modified MSWI fly ash for Cu(Ⅱ) may be attributed to electrostatic interaction and chelation effects.展开更多
Sewage sludge ash (SSA), the waste generated in sewage sludge incineration, was obtained from Wuhan Sewage Treatment Plant and used as a low-cost sorbent for removing Cu(Ⅱ) from wastewaters. The sorbent was first mod...Sewage sludge ash (SSA), the waste generated in sewage sludge incineration, was obtained from Wuhan Sewage Treatment Plant and used as a low-cost sorbent for removing Cu(Ⅱ) from wastewaters. The sorbent was first modified with 5 % sulfuric acid to increase its sorption capacity. The specific surface area, porosity, cation-exchange capacity (CEC) and pH ZPC of the sorbent were measured. Batch experiments were made to study the effect of contact time, solution pH value and temperature on sorption. Both Langmuir and Freundlich models well described the Cu(Ⅱ) sorption process, with correlation coefficient (R 2) values of 0.993 4 and 0.989 9 respectively. And the sorption process follows the Lagergren first order kinetic model. The equilibrium sorption capacity of acidified SSA to Cu(Ⅱ) is estimated to be 7.78 mg/g under optimal conditions.展开更多
Cross-linked chitosan(CS),cross-linked chitosan/graphene(CS/RGO10) and cross-linked chitosan/graphene oxide(CS/GO10) were prepared as adsorbents for Cu(Ⅱ).The effects of pH,contact time,adsorbent dosage and initial c...Cross-linked chitosan(CS),cross-linked chitosan/graphene(CS/RGO10) and cross-linked chitosan/graphene oxide(CS/GO10) were prepared as adsorbents for Cu(Ⅱ).The effects of pH,contact time,adsorbent dosage and initial concentration of Cu(Ⅱ) on the adsorbing abilities of CS,CS/RGO10 and CS/GO10 to Cu(Ⅱ) were investigated.The results demonstrate that the adsorption capacities of CS/GO10 and CS/RGO10 are greater than that of CS,especially at pH 5.0 and the adsorption capacities are 202.5,150 and 137.5 mg/g,respectively.Their behaviors obey the Freundlich isotherm model very well.Additionally,CS/GO10 has the shortest time to achieve adsorption equilibrium among them and can be used as a perspective adsorbent for Cu(Ⅱ).展开更多
基金supported by the National Natural Science Foundation of China(Nos.11605275 and 11675247)。
文摘In this study,to efficiently remove Pb(Ⅱ) from aqueous environments,a novel L-serine-modified polyethylene/polypropylene nonwoven fabric sorbent(NWF-serine)was fabricated through the radiation grafting of glycidyl methacrylate and subsequent L-serine modification.The effect of the absorbed dose was investigated in the range of 5–50 kGy.NWF-serine was characterized by Fourier transform infrared spectroscopy,thermogravimetric analysis,and scanning electron microscopy.Batch adsorption tests were conducted to investigate the influences of pH,adsorption time,temperature,initial concentration,and sorbent dosage on the Pb(Ⅱ) adsorption performance of NWF-serine.The results indicated that Pb(Ⅱ) adsorption onto NWF-serine was an endothermic process,following the pseudo-second-order kinetic model and Langmuir isotherm model.The saturated adsorption capacity was 198.1 mg/g.NWF-serine exhibited Pb(Ⅱ) removal rates of 99.8% for aqueous solutions with initial concentrations of 100 mg/L and 82.1% for landfill leachate containing competitive metal ions such as Cd,Cu,Ni,Mn,and Zn.Furthermore,NWF-serine maintained 86% of its Pb(Ⅱ) uptake after five use cycles.The coordination of the carboxyl and amino groups with Pb(Ⅱ) was confirmed using X-ray photoelectron spectroscopy and extended X-ray absorption fine structure analysis.
基金supported by the key program of the National Natural Science Foundation of China(52236008).
文摘High concentrations of copper ions(Cu(Ⅱ)) in water will pose health risks to humans and the ecological environment. Therefore, this study aims to utilize ultrasonic-cured modified municipal solid waste incineration(MSWI) fly ash for Cu(Ⅱ) adsorption to achieve the purpose of “treating waste by waste.” The effects of p H, adsorption time, initial concentration, and temperature on the modified MSWI fly ash’s adsorption efficiency were systematically studied in this article. The adsorption performance of the modified MSWI fly ash can be enhanced by the ultrasonic modification. At pH = 2, 3 and 4, the adsorption capacity of the modified MSWI fly ash for Cu(Ⅱ) increased by 2.7, 1.9 and 1.2 times, respectively. Furthermore, it was suggested that the adsorption process of the modified MSWI fly ash can be better simulated by the pseudo-second-order kinetic model, with a maximum adsorption capacity calculated by the Langmuir model of 24.196 mg.g-1. Additionally, the adsorption process is spontaneous,endothermic, and chemisorption-dominated from the thermodynamic studies(ΔH and ΔS > 0, ΔG < 0).Finally, the enhanced adsorption performance of the modified MSWI fly ash for Cu(Ⅱ) may be attributed to electrostatic interaction and chelation effects.
文摘Sewage sludge ash (SSA), the waste generated in sewage sludge incineration, was obtained from Wuhan Sewage Treatment Plant and used as a low-cost sorbent for removing Cu(Ⅱ) from wastewaters. The sorbent was first modified with 5 % sulfuric acid to increase its sorption capacity. The specific surface area, porosity, cation-exchange capacity (CEC) and pH ZPC of the sorbent were measured. Batch experiments were made to study the effect of contact time, solution pH value and temperature on sorption. Both Langmuir and Freundlich models well described the Cu(Ⅱ) sorption process, with correlation coefficient (R 2) values of 0.993 4 and 0.989 9 respectively. And the sorption process follows the Lagergren first order kinetic model. The equilibrium sorption capacity of acidified SSA to Cu(Ⅱ) is estimated to be 7.78 mg/g under optimal conditions.
基金Projects(51071067,21271069,J1210040,51238002) supported by the National Natural Science Foundation of ChinaProjects(2013GK3015,2012SK3170) supported by the Science and Technology Program of Hunan Province,China
文摘Cross-linked chitosan(CS),cross-linked chitosan/graphene(CS/RGO10) and cross-linked chitosan/graphene oxide(CS/GO10) were prepared as adsorbents for Cu(Ⅱ).The effects of pH,contact time,adsorbent dosage and initial concentration of Cu(Ⅱ) on the adsorbing abilities of CS,CS/RGO10 and CS/GO10 to Cu(Ⅱ) were investigated.The results demonstrate that the adsorption capacities of CS/GO10 and CS/RGO10 are greater than that of CS,especially at pH 5.0 and the adsorption capacities are 202.5,150 and 137.5 mg/g,respectively.Their behaviors obey the Freundlich isotherm model very well.Additionally,CS/GO10 has the shortest time to achieve adsorption equilibrium among them and can be used as a perspective adsorbent for Cu(Ⅱ).
