The escalating production of industrial solid waste,combined with the dwindling availability of natural resources,has intensified the focus on waste recycling.However,the heterogeneity and complexity of waste pose sig...The escalating production of industrial solid waste,combined with the dwindling availability of natural resources,has intensified the focus on waste recycling.However,the heterogeneity and complexity of waste pose significant challenges to determining process parameters.In this study,burnt coal cinder(BCC),granite powder(GP),and high-calcium fly ash(Class-C FA)were used as raw materials,and the response surface methodology(RSM)and single-factor experiments were applied to optimize the process parameters for geopolymer preparation.The optimized precursor powder composition was determined to be a mass ratio of 1.6:0.9:7.3 for BCC,GP,and Class-C FA.The NaOH-precursor powder ratio and liquid-solid ratio were adjusted to 0.084 and 0.222,respectively.The curing condition was set at 80℃ for 24 h.The resulting 28 d-aged multi-solid wastes-based geopolymer exhibited a high compressive strength of61.34 MPa.The microstructure,mineral phase,and atomic bonding of geopolymers were investigated using X-ray diffraction(XRD),thermal analysis(TA),Fourier transform infrared spectroscopy(FTIR),and scanning electron microscopy with energy dispersive spectroscopy(SEM-EDS).Findings indicate that the compressive strength of geopolymer is most significantly influenced by the Class-C FA,followed by BCC.Furthermore,a minor addition of GP can optimize the structural density of the geopolymer.The Ca present in the Class-C FA participates in the geopolymerization,forming a hybrid N-(C)-A-S-H gel.RSM optimization facilitates the synergistic utilization of multi-solid wastes,ensuring an even distribution of gel and filler.This research establishes a theoretical framework for optimizing the preparation parameters of multi-solid wastes-based geopolymer and its subsequent applications;it holds significant scientific implications for the circular economy,resource transformation,and environmental conservation.展开更多
A coordinative disposal process for treatment of electroplating sludge and stainless steel pickle waste liquid containing Cu, Ni, Zn, Cr and Fe etc., has been developed to recover valuable metals and to eliminate poll...A coordinative disposal process for treatment of electroplating sludge and stainless steel pickle waste liquid containing Cu, Ni, Zn, Cr and Fe etc., has been developed to recover valuable metals and to eliminate pollution. The recovery of Cu, Ni, Zn and Cr is 94%, 91%, 90% and 95%, respectively. The ammonia was recycled by the simplified process of CaO caustic distillation. The precipitated product of Cu, Ni and Zn obtained from caustic distillation of ammonia was separated by extraction or high\|pressure hydrogen reduction in an autoclave. The qualified metal salt products were obtained through extraction. The rich chromium residue from coordinative disposal was subjected to recover Cr by hydrothermal oxidation in NaOH medium and Fe\-3O\-4 was synthesized by wet methods from the residue produced by extracting Cr. Cr was a stable chemical fixed in Fe\-3O\-4 and harmless. The recovery process has been used in a pilot plant with sludge production capacity of 2000 t/a.展开更多
As one of the top ten environmental problems to be solved in the world,marine plastic waste and microplastic pollution seriously affect the health of marine ecosystems and the sustainable development of Marine economi...As one of the top ten environmental problems to be solved in the world,marine plastic waste and microplastic pollution seriously affect the health of marine ecosystems and the sustainable development of Marine economies.It is necessary to promote the establishment of a scientific and systematic Marine plastic waste and microplastic pollution control system and take strong measures to fundamentally curb and reverse the trend of marine pollution intensification in China.This paper first explains the practical significance of marine plastic waste and microplastic pollution control from three aspects:the sustainable development of the blue economy,the structural upgrading of the pan-plastic industry,and the improvement of public health awareness.Secondly,the particularity of marine plastic waste and microplastic pollution control system is summarized from three aspects of formation mechanism,migration path and damage performance.Then,it identifies domestic and international governance strategies and action plans from the perspectives of mechanism,subject,object,and measures,summarizes existing problems in the existing marine plastic waste and microplastic pollution control system,and gives directions for future improvement.Finally,some countermeasures and suggestions are put forward to accelerate the construction of China’s marine plastic waste and microplastic pollution control system,including the formation of a cross sectoral integrated land and sea control system,a full life cycle waste management process,a multi-participation model for marine ecological and environmental governance,and a global marine pollution prevention and control system.展开更多
Developing efficient and environmentally friendly metal recovery technologies from secondary resources is crucial for enhancing resource utilization and promoting environmental sustainability.However,metals with simil...Developing efficient and environmentally friendly metal recovery technologies from secondary resources is crucial for enhancing resource utilization and promoting environmental sustainability.However,metals with similar physicochemical properties pose significant challenges in the recovery process,particularly for nickel and cobalt.Herein,we present a coordination-regulated approach utilizing water-,temperature-,and pH-codrived to achieve sequential precipitation recovery of nickel and cobalt from waste choline chloride/ethylene glycol(Ethaline)electrolyte containing Ni(Ⅱ)and Co(Ⅱ)ions.By carefully adjusting water content,temperature,and pH,we can control the speciation of Ni(Ⅱ)([NiCl(H_(2)O)_(2)(EG)_(2)]+)and Co(Ⅱ)([CoCl_(2)(H_(2)O)_(2)(EG)_(2)]_(0))ions in the Ethaline-based electrolyte,thereby facilitating nickel preferential precipitation.Additionally,further introducing water into the Co(Ⅱ)-rich phase promotes the formation of[CoCl(H_(2)O)_(3)(EG)_(2)]t complex ions,leading to efficient separation of cobalt.When oxalic acid is used as a precipitant,the recovery efficiencies for nickel and cobalt reach 96.3%and 97.5%,respectively,with purities of 97.8%and 98.5%.Importantly,distilling the water-containing solvent allows for regeneration of Ethaline with a yield rate as high as 97.1%,while maintaining its structural stability.This proposed strategy offers a promising pathway for sustainable metal recovery from spent Ethaline electrolytes containing metal ions while enabling solvent regeneration.展开更多
Hydrophilic chelators are crucial for coordinating and separating radioactive f-block elements in nuclear fuel recycling,hazardous waste treatment,environmental remediation,radiopharmaceuticals,and related fields.Howe...Hydrophilic chelators are crucial for coordinating and separating radioactive f-block elements in nuclear fuel recycling,hazardous waste treatment,environmental remediation,radiopharmaceuticals,and related fields.However,their development and understanding lag behind their lipophilic counterparts.This review summarizes the development of hy-drophilic ligands across four categories based on their structural similarities and chronological order.For each category,representative examples are discussed,highlighting their advantages and disadvantages.The review also benchmarks ligands from different groups,outlines current design challenges,and emphasizes the importance of establishing structure-function relationships to guide future ligand design.Additionally,we propose four novel f-block chelating ligands,some of which have shown efficiency in solid-liquid or membrane-based radionuclide separation,aiming to inspire the search for more robust systems for f-block element utilization and recycling.This review aims to provide a comprehensive overview of hydrophilic f-block element chelators and suggest promising approaches for future ligand development.展开更多
基金supported by the Fundamental Research Funds for the Central Universities,China(No.104972025RSCrc0005)the Science and Technology Project of Shaanxi Yanchang Petroleum(Group)Co.,LTD,China(No.yc-whlg-2023ky-03)。
文摘The escalating production of industrial solid waste,combined with the dwindling availability of natural resources,has intensified the focus on waste recycling.However,the heterogeneity and complexity of waste pose significant challenges to determining process parameters.In this study,burnt coal cinder(BCC),granite powder(GP),and high-calcium fly ash(Class-C FA)were used as raw materials,and the response surface methodology(RSM)and single-factor experiments were applied to optimize the process parameters for geopolymer preparation.The optimized precursor powder composition was determined to be a mass ratio of 1.6:0.9:7.3 for BCC,GP,and Class-C FA.The NaOH-precursor powder ratio and liquid-solid ratio were adjusted to 0.084 and 0.222,respectively.The curing condition was set at 80℃ for 24 h.The resulting 28 d-aged multi-solid wastes-based geopolymer exhibited a high compressive strength of61.34 MPa.The microstructure,mineral phase,and atomic bonding of geopolymers were investigated using X-ray diffraction(XRD),thermal analysis(TA),Fourier transform infrared spectroscopy(FTIR),and scanning electron microscopy with energy dispersive spectroscopy(SEM-EDS).Findings indicate that the compressive strength of geopolymer is most significantly influenced by the Class-C FA,followed by BCC.Furthermore,a minor addition of GP can optimize the structural density of the geopolymer.The Ca present in the Class-C FA participates in the geopolymerization,forming a hybrid N-(C)-A-S-H gel.RSM optimization facilitates the synergistic utilization of multi-solid wastes,ensuring an even distribution of gel and filler.This research establishes a theoretical framework for optimizing the preparation parameters of multi-solid wastes-based geopolymer and its subsequent applications;it holds significant scientific implications for the circular economy,resource transformation,and environmental conservation.
文摘A coordinative disposal process for treatment of electroplating sludge and stainless steel pickle waste liquid containing Cu, Ni, Zn, Cr and Fe etc., has been developed to recover valuable metals and to eliminate pollution. The recovery of Cu, Ni, Zn and Cr is 94%, 91%, 90% and 95%, respectively. The ammonia was recycled by the simplified process of CaO caustic distillation. The precipitated product of Cu, Ni and Zn obtained from caustic distillation of ammonia was separated by extraction or high\|pressure hydrogen reduction in an autoclave. The qualified metal salt products were obtained through extraction. The rich chromium residue from coordinative disposal was subjected to recover Cr by hydrothermal oxidation in NaOH medium and Fe\-3O\-4 was synthesized by wet methods from the residue produced by extracting Cr. Cr was a stable chemical fixed in Fe\-3O\-4 and harmless. The recovery process has been used in a pilot plant with sludge production capacity of 2000 t/a.
基金This study is supported by the Grant from National Natural Science Foundation of China[Grant No.72004114]the Grant from National Social Science Fund of China[Grant No.18ZDA115]+1 种基金the Innovative Research Group Project of the National Foundation of China[Grant No.71721002]the Grant from China Postdoc‐toral Science Foundation[Grant No.2020M670370].
文摘As one of the top ten environmental problems to be solved in the world,marine plastic waste and microplastic pollution seriously affect the health of marine ecosystems and the sustainable development of Marine economies.It is necessary to promote the establishment of a scientific and systematic Marine plastic waste and microplastic pollution control system and take strong measures to fundamentally curb and reverse the trend of marine pollution intensification in China.This paper first explains the practical significance of marine plastic waste and microplastic pollution control from three aspects:the sustainable development of the blue economy,the structural upgrading of the pan-plastic industry,and the improvement of public health awareness.Secondly,the particularity of marine plastic waste and microplastic pollution control system is summarized from three aspects of formation mechanism,migration path and damage performance.Then,it identifies domestic and international governance strategies and action plans from the perspectives of mechanism,subject,object,and measures,summarizes existing problems in the existing marine plastic waste and microplastic pollution control system,and gives directions for future improvement.Finally,some countermeasures and suggestions are put forward to accelerate the construction of China’s marine plastic waste and microplastic pollution control system,including the formation of a cross sectoral integrated land and sea control system,a full life cycle waste management process,a multi-participation model for marine ecological and environmental governance,and a global marine pollution prevention and control system.
基金the National Natural Science Foundation of China(52361039,21962008)Yunnan Ten Thousand Talents Plan Young&Elite Talents Project(YNWR-QNBJ-2018-346).
文摘Developing efficient and environmentally friendly metal recovery technologies from secondary resources is crucial for enhancing resource utilization and promoting environmental sustainability.However,metals with similar physicochemical properties pose significant challenges in the recovery process,particularly for nickel and cobalt.Herein,we present a coordination-regulated approach utilizing water-,temperature-,and pH-codrived to achieve sequential precipitation recovery of nickel and cobalt from waste choline chloride/ethylene glycol(Ethaline)electrolyte containing Ni(Ⅱ)and Co(Ⅱ)ions.By carefully adjusting water content,temperature,and pH,we can control the speciation of Ni(Ⅱ)([NiCl(H_(2)O)_(2)(EG)_(2)]+)and Co(Ⅱ)([CoCl_(2)(H_(2)O)_(2)(EG)_(2)]_(0))ions in the Ethaline-based electrolyte,thereby facilitating nickel preferential precipitation.Additionally,further introducing water into the Co(Ⅱ)-rich phase promotes the formation of[CoCl(H_(2)O)_(3)(EG)_(2)]t complex ions,leading to efficient separation of cobalt.When oxalic acid is used as a precipitant,the recovery efficiencies for nickel and cobalt reach 96.3%and 97.5%,respectively,with purities of 97.8%and 98.5%.Importantly,distilling the water-containing solvent allows for regeneration of Ethaline with a yield rate as high as 97.1%,while maintaining its structural stability.This proposed strategy offers a promising pathway for sustainable metal recovery from spent Ethaline electrolytes containing metal ions while enabling solvent regeneration.
基金the National Natural Science Foundation of China (U2067213, 22325603)the National Natural Science Foundation of China (22105205)the Beijing Natural Science Foundation (2232002)
文摘Hydrophilic chelators are crucial for coordinating and separating radioactive f-block elements in nuclear fuel recycling,hazardous waste treatment,environmental remediation,radiopharmaceuticals,and related fields.However,their development and understanding lag behind their lipophilic counterparts.This review summarizes the development of hy-drophilic ligands across four categories based on their structural similarities and chronological order.For each category,representative examples are discussed,highlighting their advantages and disadvantages.The review also benchmarks ligands from different groups,outlines current design challenges,and emphasizes the importance of establishing structure-function relationships to guide future ligand design.Additionally,we propose four novel f-block chelating ligands,some of which have shown efficiency in solid-liquid or membrane-based radionuclide separation,aiming to inspire the search for more robust systems for f-block element utilization and recycling.This review aims to provide a comprehensive overview of hydrophilic f-block element chelators and suggest promising approaches for future ligand development.
