Effective recovery of high-value heavy metals from electroplating wastewater is of great significance,but recovering nickel ions from real electroplating wastewater as nickel sheet has not been reported.In this study,...Effective recovery of high-value heavy metals from electroplating wastewater is of great significance,but recovering nickel ions from real electroplating wastewater as nickel sheet has not been reported.In this study,the pilot-scale fixed-bed resin adsorption was conducted to recover Ni(Ⅱ)ions from real nickel plating wastewater,and then the concentrated Ni(Ⅱ)ions in the regenerated solution were reduced to nickel sheet via electrodeposition.A commercial cation-exchange resin was selected and the optimal resin adsorption and regeneration conditions were investigated.The resin exhibited an adsorption capacity of 63 mg/g for Ni(Ⅱ)ions,and the average amount of treated water was 84.6 bed volumes(BV)in the pilot-scale experiments.After the adsorption by two ion-exchange resin columns in series and one chelating resin column,the concentrations of Ni(Ⅱ)in the treated wastewater were below 0.1 mg/L.After the regeneration of the spent resin using 3 BVof 4%(w/w)HC1 solution,1.5 BV of concentrated neutral nickel solution(>30 g/L)was obtained and used in the subsequent electrodeposition process.Using the aeration method,alkali and water required in resin activation process were greatly reduced to 2 BV and 3 BV,respectively.Under the optimal electrodeposition conditions,95.6%of Ni(Ⅱ)in desorption eluent could be recovered as the elemental nickel on the cathode,llie total treatment cost for the resin adsorption and regeneration as well as the electrodeposition was calculated.展开更多
The separation of radionuclides is critical for the sustainable development of nuclear energy. It is urgent to design and prepare functionalized materials for efficient radionuclides separation. Porous materials are c...The separation of radionuclides is critical for the sustainable development of nuclear energy. It is urgent to design and prepare functionalized materials for efficient radionuclides separation. Porous materials are considered excellent candidates for the separation of radionuclides under complex conditions due to their high specific surface areas, tunable pore structures and controllable functionalities. In this review, we summarized the design, preparation and functionalization of porous materials and their application for separation of radionuclides in the past five years, discussed the separation performance and analyzed the structure-activity relationship between various radionuclides and porous materials, and systematically clarified their characterization and mechanism of different type porous materials. We also introduced the detection, irradiation and chemical toxicity of different reflective radionuclides.展开更多
Herein,a biochar-based composite(Ti_(3)C_(2)T_(x)@biochar-PDA/PEI)was constructed by decorating Ti_(3)C_(2)T_(x) and polydopamine on coconut shell biochar via electrostatic self-assembly method.Different characterizat...Herein,a biochar-based composite(Ti_(3)C_(2)T_(x)@biochar-PDA/PEI)was constructed by decorating Ti_(3)C_(2)T_(x) and polydopamine on coconut shell biochar via electrostatic self-assembly method.Different characterization techniques were applied to explore the structure,morphology and composition of the sorbents.It was found that the higher porosity and diverse functional groups were conducive for Ti_(3)C_(2)T_(x)@biochar-PDA/PEI to capture radionuclides,and the water environmental conditions made a great contribution to the adsorption process.The process of removing U(Ⅵ)/Cs(Ⅰ)well complied with the Langmuir isotherm and Pseudo-second-order equations,which indicated that the single layer chemical adsorption occurred on the solid liquid interface.Meanwhile,this produced composite exhibited superior removal performance under complex co-existing ion environment,and the maximum adsorption amounts of U(Ⅵ)and Cs(Ⅰ)reached up to 239.7 and 40.3 mg g^(−1).Impressively,this adsorbent still exhibited good adsorption performance after three cycles of regeneration.The spectral analysis and DFT calculation demonstrated that adsorption of U(Ⅵ)might be a chemical process,while the adsorption of Cs(Ⅰ)should be ion exchange or electrostatic attraction.This study demonstrated the potential application of Ti_(3)C_(2)T_(x)@biochar-PDA/PEI as an effective remediation strategy for radioactive wastewater cleanup.展开更多
文摘Effective recovery of high-value heavy metals from electroplating wastewater is of great significance,but recovering nickel ions from real electroplating wastewater as nickel sheet has not been reported.In this study,the pilot-scale fixed-bed resin adsorption was conducted to recover Ni(Ⅱ)ions from real nickel plating wastewater,and then the concentrated Ni(Ⅱ)ions in the regenerated solution were reduced to nickel sheet via electrodeposition.A commercial cation-exchange resin was selected and the optimal resin adsorption and regeneration conditions were investigated.The resin exhibited an adsorption capacity of 63 mg/g for Ni(Ⅱ)ions,and the average amount of treated water was 84.6 bed volumes(BV)in the pilot-scale experiments.After the adsorption by two ion-exchange resin columns in series and one chelating resin column,the concentrations of Ni(Ⅱ)in the treated wastewater were below 0.1 mg/L.After the regeneration of the spent resin using 3 BVof 4%(w/w)HC1 solution,1.5 BV of concentrated neutral nickel solution(>30 g/L)was obtained and used in the subsequent electrodeposition process.Using the aeration method,alkali and water required in resin activation process were greatly reduced to 2 BV and 3 BV,respectively.Under the optimal electrodeposition conditions,95.6%of Ni(Ⅱ)in desorption eluent could be recovered as the elemental nickel on the cathode,llie total treatment cost for the resin adsorption and regeneration as well as the electrodeposition was calculated.
基金supported by the National Natural Science Foundation of China (22341602, U2067215, 22006036, U2167218, U2341289, 22327807, 22176077)the Beijing Outstanding Young Scientist Program, and the Fundamental Research Funds for the Central Universities (lzujbky-2023-stlt01)。
文摘The separation of radionuclides is critical for the sustainable development of nuclear energy. It is urgent to design and prepare functionalized materials for efficient radionuclides separation. Porous materials are considered excellent candidates for the separation of radionuclides under complex conditions due to their high specific surface areas, tunable pore structures and controllable functionalities. In this review, we summarized the design, preparation and functionalization of porous materials and their application for separation of radionuclides in the past five years, discussed the separation performance and analyzed the structure-activity relationship between various radionuclides and porous materials, and systematically clarified their characterization and mechanism of different type porous materials. We also introduced the detection, irradiation and chemical toxicity of different reflective radionuclides.
基金Zhejiang Provincial Natural Science Foundation of China under Grant No.LQ23B060002China Postdoctoral Science Foundation under Grant No.2021M702911.
文摘Herein,a biochar-based composite(Ti_(3)C_(2)T_(x)@biochar-PDA/PEI)was constructed by decorating Ti_(3)C_(2)T_(x) and polydopamine on coconut shell biochar via electrostatic self-assembly method.Different characterization techniques were applied to explore the structure,morphology and composition of the sorbents.It was found that the higher porosity and diverse functional groups were conducive for Ti_(3)C_(2)T_(x)@biochar-PDA/PEI to capture radionuclides,and the water environmental conditions made a great contribution to the adsorption process.The process of removing U(Ⅵ)/Cs(Ⅰ)well complied with the Langmuir isotherm and Pseudo-second-order equations,which indicated that the single layer chemical adsorption occurred on the solid liquid interface.Meanwhile,this produced composite exhibited superior removal performance under complex co-existing ion environment,and the maximum adsorption amounts of U(Ⅵ)and Cs(Ⅰ)reached up to 239.7 and 40.3 mg g^(−1).Impressively,this adsorbent still exhibited good adsorption performance after three cycles of regeneration.The spectral analysis and DFT calculation demonstrated that adsorption of U(Ⅵ)might be a chemical process,while the adsorption of Cs(Ⅰ)should be ion exchange or electrostatic attraction.This study demonstrated the potential application of Ti_(3)C_(2)T_(x)@biochar-PDA/PEI as an effective remediation strategy for radioactive wastewater cleanup.
