Sludge,the massive by-product of the sewage system,became a major challenge for the wastewater treatment industry.Yet,conventional methods often face challenges like low efficiency,high energy consumption,and environm...Sludge,the massive by-product of the sewage system,became a major challenge for the wastewater treatment industry.Yet,conventional methods often face challenges like low efficiency,high energy consumption,and environmental pollution.Especially,the improper treatment and disposal of toxic sludge generated from different industrial processes or specific wastewater treatment operations exerted significant pressure and threat to hydrosphere,pedosphere,atmosphere and even biosphere.展开更多
The acid leaching residue(ALR)of ionic rare earth(IRE)concentrates containing radioactive elements such as thorium(Th)is classified as low-level radioactive waste.ALR holds valuable strategic resources such as rare ea...The acid leaching residue(ALR)of ionic rare earth(IRE)concentrates containing radioactive elements such as thorium(Th)is classified as low-level radioactive waste.ALR holds valuable strategic resources such as rare earth and Th,while improper long-term heaping storage of ALR poses a substantial environmental risk.This paper proposes a comprehensive process involving low-temperature roasting,hydrochloric acid leaching,single extractant enrichment,and stepwise stripping to recover rare earth elements and thorium from ALR.The achieved leaching efficiencies are 80.11%of LnY,99.43%of Sc(Ⅲ),and 98.67%of Th(Ⅳ)after the carbonization of the organic phase in the ALR through low-temperature roasting.Despite large amounts of acid and impurities present in the leachate,2-ethylhexyl phosphonic acid mono 2-ethylhexyl ester(HEHEHP)still exhibits nearly 100%extraction efficiency for Sc(Ⅲ)and Th(Ⅳ).The effective separation of LnY,Th(Ⅳ),and Sc(Ⅲ)was achieved by implementing fractional extraction enrichment of Th(Ⅳ)and Sc(Ⅲ),followed by Th(Ⅳ)removal through H_(2)SO_(4)and Sc(Ⅲ)removal via NaOH from the loaded organic phase.This scheme successfully achieves a recovery of RE and Th and offers a viable solution for the safe disposal of ALR.展开更多
The global energy landscape is undergoing a profound transformation,with wind energy,especially wind power,gaining increasing prominence due to its clean,renewable nature.However,as the installed capacity of wind powe...The global energy landscape is undergoing a profound transformation,with wind energy,especially wind power,gaining increasing prominence due to its clean,renewable nature.However,as the installed capacity of wind power continues to expand,the disposal of waste wind turbine blades(WWTB)has emerged as a significant challenge.These blades are predominantly composed of epoxy resin(EP)polymers,carbon fibers(CFs),and glass fibers(GFs).Improper disposal not only exacerbates environmental concerns but also leads to the loss of valuable resources,particularly carbon-based materials.Pyrolysis technology,a versatile and environmentally sustainable method for resource recovery,has garnered considerable attention in the context of WWTB disposal.This work presents a comprehensive review of the pyrolytic recycling of WWTB,focusing on the principles and classifications of pyrolysis technology,key factors influencing the pyrolysis process,as well as the pyrolysis methods,equipment,products,and their applications.Through an in-depth analysis of the current research on the pyrolytic recycling of WWTB,this review identifies critical unresolved issues in the field and provides a forward-looking perspective on emerging research trends.展开更多
The rapid expansion of the photovoltaic industry has generated heavily oxidized waste silicon(wSi),which hinders efficient recycling owing to its small particle size and uncontrolled surface oxidation.This study intro...The rapid expansion of the photovoltaic industry has generated heavily oxidized waste silicon(wSi),which hinders efficient recycling owing to its small particle size and uncontrolled surface oxidation.This study introduces a molten salt electrochemical strategy for converting photovoltaic wSi into NiSi_(2)-silicon nanorods(NiSi_(2)-SiNRs)as high-performance anode materials for lithium-ion batteries.A stable oxidized passivation layer is formed on the wSi surface via controlled oxidation,and further in situ generated highly active NiSi_(2) droplets.The molten salt electric field modulates the surface energy of silicon,while particle integration drives localized directional growth,enabling the self-assembly of NiSi_(2)-SiNRs composites.These NiSi_(2)-SiNRs anodes exhibit rapid ion transport and effective strain buffering.The high aspect ratio of SiNRs and the presence of retained NiSi_(2) facilitate both longitudinal and transverse Li^(+) diffusion.Owing to their robust structural design,the NiSi_(2)-SiNRs anode achieves an excellent initial Coulombic efficiency of 91.61%and retains 72.99%of its capacity after 800 cycles at 2 A·g^(−1).This study establishes a model system for investigating silicide/silicon interfaces in molten salt electrochemical synthesis and provides an effective strategy for upcycling photovoltaic wSi into high-performance lithium-ion battery anodes.展开更多
Red mud is a byproduct of alumina refining of bauxite ores,and is a significant source for extracting scandium.However,a large amount of iron in red mud makes it difficult to recover scandium because Fe(III) and Sc(Ⅲ...Red mud is a byproduct of alumina refining of bauxite ores,and is a significant source for extracting scandium.However,a large amount of iron in red mud makes it difficult to recover scandium because Fe(III) and Sc(Ⅲ) have similar physicochemical properties.In this study,a new method was developed for selective separation of iron and scandium in acid leachate of red mud using D201 resin.Theoretical calculations indicate that the ferric species mainly exists as FeCl3 or FeCl4-at chloride concentration above 6.65 mol/L,while scandium still exists as SCl2+,making it possible to selectively separate iron fro m scandium through anion resin adso rption.The factors affecting the adso rption of iron and scandium such as chloride conce ntratio n,resin dosage,adso rption time,and temperature were evaluated in batch experiments,The Langmuir model was successfully applied to both iron and scandium adsorption,and the maximum adsorption capacities of iron and scandium are 147.06 and 0.95 mg/g,respectively,indicating a significant difference between iron and scandium.Raman analysis further demonstrates that the iron is adsorbed onto D201 resin as FeCl4 anion.展开更多
A vacuum membrane distillation(VMD)process with permeate fractional condensation on membrane downstream has been developed for simultaneous recovery of phosphorus and nitrogen from liquid digestate.The polytetrafluoro...A vacuum membrane distillation(VMD)process with permeate fractional condensation on membrane downstream has been developed for simultaneous recovery of phosphorus and nitrogen from liquid digestate.The polytetrafluoroethylene(PTFE)membrane flux could reach 6000 g·m-2·h-1 with the rejection efficiency of total phosphorus(TP)over 0.99,under the condition of flowrate being 120 L·h-1 and temperature being 40°C.Membrane fouling occurred with a film of organics and microorganism deposited on the surface of the membrane.Membrane flux could be reversed after the membrane was rinsed by water.Higher feed temperature and flowrate could improve the membrane flux,while hardly affect the rejection efficiency of total phosphorus.The concentration of TP could reach 1600 mg·L-1 after membrane distillation,which is about 5 times of that in initial liquid digestate.On the downstream of the membrane,some of the permeate vapor was condensed under the vacuum condition and most of water was collected here.The remaining vapor enriched with total nitrogen(TN)was compressed and pumped to the atmospheric condition to condense.The TN concentration in atmospheric condensate was as high as 7000 mg·L-1 with the process separation factor for ammonia being enhanced to 114.展开更多
Based on the principle of bacterial leaching and bacterial metallurgy,a novel technology for the detoxification of chromium-containing slag by Achromobacter sp.CH-1 and chromium recovery was proposed.Strain CH-1 cell ...Based on the principle of bacterial leaching and bacterial metallurgy,a novel technology for the detoxification of chromium-containing slag by Achromobacter sp.CH-1 and chromium recovery was proposed.Strain CH-1 cell morphology before and after Cr(Ⅵ) reduction was observed with a scanning electron microscope(SEM),and the reduction product is found to adhere to terminals of CH-1 cells.Energy-dispersive X-ray(EDX) and electron paramagnetic resonance(EPR) analyses reveal that the main component of the reduction product is Cr(Ⅲ).Furthermore,small and large-scale demonstration projects reveal that Achromobacter sp.can be used to detoxify chromium-containing slag and to selectively recover chromium by using this novel technique.Chromium recovery rate increases with decreasing particle sizes of chromium-containing slag and slagheap height.Chromium recovery rates in 10 t/batch and 20 t/batch of on-site demonstration projects for chromium-containing slag detoxification are more than 90%.展开更多
Recovery of Ni-Cd batteries was studied by a self-designed vacuum-aided recovering system under laboratory conditions. The fundamental research on a process of disassembling and recovering selected materials from Ni-C...Recovery of Ni-Cd batteries was studied by a self-designed vacuum-aided recovering system under laboratory conditions. The fundamental research on a process of disassembling and recovering selected materials from Ni-Cd batterieswas conducted. The impacts of temperature, pressure and time were studied respectively. The mechanism of vacuum thermal recovering was also discussed. The results show that: Ni-Cd batteries can be recovered effectively byvacuum-aided recovering system at 573~1173 K. At constant pressure, the increase of temperature can improve theseparating efficiency of cadmium. When the temperature is 1173 K, the cadmium can evaporate completely fromthe residue during 3 h at 10 Pa. The reduction of pressure in the certain range is effective to separate cadmium byvacuum distillation. Distillation time is a very important factor affecting separation of cadmium.展开更多
UiO-66 series metal-organic framework materials(MOFs)are typical porous materials assembled by Zr^(4+) with a large mass-to-nucleus ratio and terephthalic acid ligands,which form tetrahedral and octahedral cages arran...UiO-66 series metal-organic framework materials(MOFs)are typical porous materials assembled by Zr^(4+) with a large mass-to-nucleus ratio and terephthalic acid ligands,which form tetrahedral and octahedral cages arranged in a periodic triangular window pattern.Due to the strong interaction between Zr and O,UiO-66 series MOFs exhibit high thermal stability,structural stability,and chemical stability.This article mainly reviews the applications of UiO-66 and its composites in adsorption,photocatalysis,and resource utilization,while exploring the harm of pollutants to human health and the environment.In the first part,the differences in adsorption and removal mechanisms of liquid organic pollutants,heavy metals,and volatile organic compounds(VOCs)are investigated.The results show that organic pollutants are mainly removed by physical adsorption,electrostatic interactions,hydrogen bonding,andπ-πinteractions,while heavy metals are mainly removed by chemical adsorption,electrostatic interactions,reduction,and chelation.VOCs are mainly removed by the pore volume and pore size structure of the material.Heterojunction catalysis can achieve non-toxic treatment of pollutants,and this study mainly focuses on UiO-based composite materials constructed by strategies such as semiconductor composites,ion doping,and metal/dye encapsulation.In the second part,the synergistic effect between the components of UiO-based composite materials promotes the oriented and rapid separation and transfer of earriers at the material interface,thereby promoting the generation of active species such as h^(+),·O_(2)^(-) and·OH,and achieving rapid degradation of pollutants and detoxification of heavy metals.In the third part,heterojunctions can realize the resource utilization of pollutants in water and air,producing energy-type substances such as hydrogen and methanol while solving environmental problems.In addition,this article also summarizes the harm of common typical pollutants to the environment and human health.Finally,the development prospects and unresolved problems of UiO-66-based materials in water remediation,gas purification,and environmental resource utilization are reviewed.展开更多
One of the major problems of agricultural soils in the tropical regions of the Pacific is the low organic matter content.Because of the hot and humid environment,the soil organic matter(SOM)is minimal due to rapid dec...One of the major problems of agricultural soils in the tropical regions of the Pacific is the low organic matter content.Because of the hot and humid environment,the soil organic matter(SOM)is minimal due to rapid decomposition.Composted organic material is being applied on agricultural fields as an amendment to provide nutrients and enhance the organic matter content for improving the physical and chemical properties of the cultivated soils.In addition land application of composted material as a fertilizer source effectively disposes of wastes that otherwise are buried in landfills.In our soil program at the University of Guam,we are evaluating the use of organic material as an alternative to synthetic fertilizers.Its goal is to develop management strategies and use available resources for improving crop production while conserving resources and preserving environmental quality.Our case study project is designed to improve soil fertility status by using composted organic wastes and assessing how the nitrogen and other essential nutrients contribute to long-term soil fertility and crop productivity without application of synthetic fertilizers.In our pilot project,compost is produced from wood chips,grinded typhoon debris mixed with animal manure,fish feed,shredded paper and other organic wastes.Mature compost is then applied on the field at the rates of 0,5,10 and 20 t/ha as a soil amendment on the eroded cobbly soils of southern Guam.Corn is planted and monitored for growth performance and yield.The effect of land application of composted material on the SOM content and overall soil quality indices are being evaluated in this pilot study.展开更多
At present, in the process of rural environmental treatment, the garbage problem has become the main problem that currently affects the rural environmental pollution. In view of this problem, the relevant departments ...At present, in the process of rural environmental treatment, the garbage problem has become the main problem that currently affects the rural environmental pollution. In view of this problem, the relevant departments should adopt effective solutions to classify the rural solid garbage, and at the same time, recycle the valuable garbage for secondary treatment. At present, the garbage in the rural areas of China mainly comes from domestic garbage, livestock breeding waste, agricultural straw and other solid wastes. Aiming at the problems existing in the treatment process of the above pollutants, in-depth research and discussion are carried out to obtain valuable recyclable remediation plan.展开更多
Wastewater treatment significantly contributes to greenhouse gas emissions,which are further exacerbated by the environmental impact of external chemical additions.In response,microbial electrochemical wastewater refi...Wastewater treatment significantly contributes to greenhouse gas emissions,which are further exacerbated by the environmental impact of external chemical additions.In response,microbial electrochemical wastewater refining has gained prominence at the interdisciplinary frontier of wastewater resource recovery and green bio-manufacturing.Significant progress has been made in utilizing active electrodes to stimulate CO_(2) fixation rates,applying“binary electron donors”to produce high-value-added chemicals,and developing novel processes and equipment.This review explores various aspects of microbial electrochemical wastewater refining,including microbial electrochemical monitoring of water quality,chemical synthesis from diverse carbon sources,and the deployment of pilot-scale systems for generating electricity,hydrogen,and methane,as well as for in-situ remediation.Additionally,it discusses the challenges and future directions,highlighting the importance of understanding mechanisms,advancing electrocatalyst and microbial engineering,and innovating hybrid processes.In conclusion,the widespread adoption of microbial electrochemical wastewater refining is emphasized for resource recovery and sustainable chemical production,ultimately reducing environmental impact.展开更多
The efficient recovery of rhenium(Re),a scarce metal closely associated with the energy and aerospace industries,is essential for alleviating global Re resource tension.For the first time,we propose a radiosensitizati...The efficient recovery of rhenium(Re),a scarce metal closely associated with the energy and aerospace industries,is essential for alleviating global Re resource tension.For the first time,we propose a radiosensitization reduction method to selectively reclaim ReO_(4)^(−) as ReO_(2) from its aqueous solutions,utilizing a stable Hf-based metal–organic framework,Hf-BPY,as an effective radiation sensitizer.While interacting withγ-rays or electron beams(EBs),Hf-BPY provides Hf6-cluster arrays with high atomic number,exhibiting radiation attenuation ability that enhances the radiolysis of water,which further increases the yield of reductive hydrated electrons(eaq^(−))from 2.80×10^(−7) to 4.05×10^(−7) mol/J.As a clean reduction method,the reaction is propelled directly by the enriched eaq^(−),without the need for any sacrificial agents.Pure ReO_(2) is obtained with resistance to reoxidation and redissolution.This laboratory-proven approach is further scaled up to liter scale,achieving the recovery of 0.568 and 0.468 g/L of ReO_(2) usingγ-ray and EB irradiation,respectively.Along with its cyclic ability to maintain a stable reduction ratio over seven radiation cycles,this approach holds great potential for industrial Re recovery.The feasibility of radiosensitization reduction for the decontamination of heavy metal pollution is further confirmed,adding to the evidence of its prospects for broad application.展开更多
The photochemical conversion of plastic waste into valuable resources under ambient conditions is challenging.Achieving efficient photocatalytic conversion necessitates intimate contact between the photocatalyst and p...The photochemical conversion of plastic waste into valuable resources under ambient conditions is challenging.Achieving efficient photocatalytic conversion necessitates intimate contact between the photocatalyst and plastic substrate,as water molecules are readily oxidized by photogenerated holes,potentially bypassing the plastic as the electron donor.This study demonstrated a novel strategy for depositing polystyrene(PS)waste onto a photoanode by leveraging its solubility in specific organic solvents,including acetone and chloroform,thus enhancing the interface contact.We used an anodization technique to fabricate a skeleton-like porous tungsten oxide(WO_(3))structure,which exhibited higher durability against detachment from a conductive substrate than the WO_(3) photoanode fabricated using the doctor blade method.Upon illumination,the photogenerated holes were transferred from WO_(3) to PS,promoting the oxidative degradation of plastic waste under ambient conditions.Consequently,the oxidative degradation of PS on the anode side generated carbon dioxide,while the cathodic process produced hydrogen gas through water reduction.Our findings pave the way for sunlight-driven plastic waste treatment technologies that concurrently generate valuable fuels or chemicals and offer the dual benefits of cost savings and environmental protection.展开更多
As the world’s largest palm oil producer,Indonesia significantly benefits from its palm oil industry but also faces serious environmental challenges from palm oil mill effluent(POME)-a high-strength wastewater contai...As the world’s largest palm oil producer,Indonesia significantly benefits from its palm oil industry but also faces serious environmental challenges from palm oil mill effluent(POME)-a high-strength wastewater containing substantial organic matter,nutrients,suspended solids,and various chemical compounds.Sustainable and effective wastewater treatment strategies are urgently needed to address this issue.This review presents a comprehensive analysis of existing POME treatment technologies,including anaerobic digestion(AD),advanced oxidation processes(AOPs),membrane filtration,adsorption,phytoremediation,and microalgae-based systems.Each method is examined in terms of treatment efficiency,operational feasibility,and potential for imple-mentation under Indonesian conditions.While advanced processes,such as AOPs and membrane filtration,achieve high pollutant removal,they are often limited by operational costs.In contrast,biological approaches,such as AD and phytoremediation,offer both environmental benefits and economic value through the recovery of biogas,biofertilizers,and biomass.This review highlights the potential for integrating wastewater purification with resource recovery and valorization,supporting a shift toward more circular and sustainable management of POME.The insights provided are intended to guide future research,inform policy decisions,and facilitate the industrial adoption of optimized treatment systems.展开更多
The nano-MOF-303 synthesized by microwave method exhibited efficient adsorption capacity(232 mg/g)toward Ag^(+),in which the adsorption behaviors were fitted by the pseudo-second-order kinetic and the Freundlich isoth...The nano-MOF-303 synthesized by microwave method exhibited efficient adsorption capacity(232 mg/g)toward Ag^(+),in which the adsorption behaviors were fitted by the pseudo-second-order kinetic and the Freundlich isotherm model.The outstanding Ag^(+)sorption ability of nano-MOF-303 could be contributed to electrostatic interactions,weak coordination interaction of Ag-N,and Ag Cl precipitates originating from the stored Cl^(-)in nano-MOF-303.Besides the adsorbent regeneration,the formed Ag/Ag Cl onto nano-MOF-303 could produce Ag/Ag Cl/MOF-303 as a photocatalyst for sulfamethoxazole degradation under visible light.In this work,both the adsorption and photocatalysis mechanisms were clarified,which might provide insight to develop more effective adsorbents for mining the critical resource from the wastewater.展开更多
Urine consists of approximately 95%water,3.5%organic matter,and 1.5%inorganic salts.Membrane distillation(MD)offers a potential approach for urine resource utilization.To some extent,it reduces the loss of nitrogen an...Urine consists of approximately 95%water,3.5%organic matter,and 1.5%inorganic salts.Membrane distillation(MD)offers a potential approach for urine resource utilization.To some extent,it reduces the loss of nitrogen and phosphorus resources.However,MD is also accompanied by problems such as high membrane cost,membrane fouling and membrane wetting.In light of these issues,this study employs polytetrafluoroethylene(PTFE)as the separation layer and polypropylene(PP)as the support layer to make a distillation membrane.The feasibility and efficiency of the PTFE-PP membrane in intercepting and recovering nitrogen and phosphorus from source-separated urine were investigated.Results obtained through 14 days of continuous operation demonstrated that the recovery rates of nitrogen and phosphorus were 95%and 99%,respectively.The dissolved organic carbon recovery rate was 95%,and urea as well as the macromolecular organic matter in dissolved organic matter were significantly intercepted.The phosphorus content in the permeate was 0.022 mg/L,which met theⅡclass standard of China’s surface water and the basic water use standard of the United States Environmental Protection Agency.This finding reduces the pressure on sewage treatment plants.PTFE-PP distillation membrane has important potential in recovering nitrogen and phosphorus from urine and alleviating global water shortage.展开更多
Traditional treatments of zinc dross have many disadvantages,such as complicated recovering process and serious environmental pollution.In this work,a new process of chlorine removal from zinc dross by microwave was p...Traditional treatments of zinc dross have many disadvantages,such as complicated recovering process and serious environmental pollution.In this work,a new process of chlorine removal from zinc dross by microwave was proposed for solving problem of recycling the zinc dross.With better ability of absorbing the microwave than zinc oxide,the main material in zinc dross,chlorides,can be heated and evaporated rapidly during microwave roasting.Various parameters including roasting temperature,duration time and stirring speed were optimized.The microstructure of roasted materials was characterized by X-ray diffraction(XRD) and scanning electron microscope(SEM).The content of the chloride was analyzed by the method of chlorine ion selective electrode.The experiments indicate that the best duration time is 60 min with a stirring speed of 15 r/min during the microwave roasting process.The dechlorination rate reaches peak value of 88% at 700 ℃.The chlorine is removed as HCl gas when water vapor is used as activating agent,which means that it can be recovered into hydrochloride acid.展开更多
Based on field research data on farmers in 30 counties(districts)of six cities in Shandong Province,this study systematically examines the methods of disposal of livestock and poultry waste and the factors that influe...Based on field research data on farmers in 30 counties(districts)of six cities in Shandong Province,this study systematically examines the methods of disposal of livestock and poultry waste and the factors that influence them,that is,the determinants of farmers’waste disposal behaviors,using the UTAUT theoretical framework and a disordered multi-class logit model.The results show that,first,economic performance expectancy,subjective norms,farming population,and poultry and livestock breeding numbers have significant effects on the four waste recycling methods considered:direct return,compost fermentation,biogas fermentation,and fresh-packed sale.Second,annual family income has a positive effect on the direct return method.Third,compost fermentation is positively affected by farmers'knowledge,distance from sources of water,and farming scale,and negatively affected by gender and marital status.Fourth,biogas fermentation is negatively affected by the age of farmers and positively affected by the farming income ratio and environmental convenience.Finally,the most important factors affecting the four methods are subjective norms,farming scale,economic performance expectancy,and farming population.Therefore,this study proposes that policies to promote resource utilization of livestock and poultry waste must prioritize raising awareness among the farmers of the advantages of resource disposal of waste;provide reasonable subsidies for waste recycling and enhance policy applicability,pertinence,and motivation;strengthen the promotion of waste recycling technology and improve the practicality of lectures or training content;and improve relevant laws and regulations and enhance authority and usability.展开更多
Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining tech...Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining technology for residual coal of end slopes.In the proposal a conveyance road and ventilation conveyance near the slope are built,corresponding to the pit mining area and the surface coal mine dump,as well as an interval haulage tunnel and air-inlet tunnel.The outcome shows that such mining method may reduce the effect to slope stability from underground mining,it does not affect the dumping advance and has a high recovery rate of residual coal resources.The working face is timbered by single hydraulic props,transported by a scraper conveyor and supported by coal walls.This method of mining is one of layered top coal caving,with high resource recovery,low production cost where positive economic benefit can be realized.展开更多
基金supported by National Natural Science Foundation of China(Nos.52370025,22176012)BUCEA Post Graduate Innovation Project(No.PG2024086)。
文摘Sludge,the massive by-product of the sewage system,became a major challenge for the wastewater treatment industry.Yet,conventional methods often face challenges like low efficiency,high energy consumption,and environmental pollution.Especially,the improper treatment and disposal of toxic sludge generated from different industrial processes or specific wastewater treatment operations exerted significant pressure and threat to hydrosphere,pedosphere,atmosphere and even biosphere.
基金supported by the National Key Research and Development Program of China(2020YFC1909001)the Natural Science Foundation of Jiangxi Province(20202BABL214024)。
文摘The acid leaching residue(ALR)of ionic rare earth(IRE)concentrates containing radioactive elements such as thorium(Th)is classified as low-level radioactive waste.ALR holds valuable strategic resources such as rare earth and Th,while improper long-term heaping storage of ALR poses a substantial environmental risk.This paper proposes a comprehensive process involving low-temperature roasting,hydrochloric acid leaching,single extractant enrichment,and stepwise stripping to recover rare earth elements and thorium from ALR.The achieved leaching efficiencies are 80.11%of LnY,99.43%of Sc(Ⅲ),and 98.67%of Th(Ⅳ)after the carbonization of the organic phase in the ALR through low-temperature roasting.Despite large amounts of acid and impurities present in the leachate,2-ethylhexyl phosphonic acid mono 2-ethylhexyl ester(HEHEHP)still exhibits nearly 100%extraction efficiency for Sc(Ⅲ)and Th(Ⅳ).The effective separation of LnY,Th(Ⅳ),and Sc(Ⅲ)was achieved by implementing fractional extraction enrichment of Th(Ⅳ)and Sc(Ⅲ),followed by Th(Ⅳ)removal through H_(2)SO_(4)and Sc(Ⅲ)removal via NaOH from the loaded organic phase.This scheme successfully achieves a recovery of RE and Th and offers a viable solution for the safe disposal of ALR.
基金Supported by the National Natural Science Foundation of China(22468035,22468036,22368038,22308048)the Natural Science Foundation of Inner Mongolia(2024QN02018,2025MS02030)+2 种基金First-class Discipline Research Special Project of Inner Mongolia(YLXKZX-NGD-045)Inner Mongolia Autonomous Region Postgraduate Research Innovation Project(KC2024047B)Research Foundation for Introducing High-level Talents in Inner Mongolia Autonomous Region。
文摘The global energy landscape is undergoing a profound transformation,with wind energy,especially wind power,gaining increasing prominence due to its clean,renewable nature.However,as the installed capacity of wind power continues to expand,the disposal of waste wind turbine blades(WWTB)has emerged as a significant challenge.These blades are predominantly composed of epoxy resin(EP)polymers,carbon fibers(CFs),and glass fibers(GFs).Improper disposal not only exacerbates environmental concerns but also leads to the loss of valuable resources,particularly carbon-based materials.Pyrolysis technology,a versatile and environmentally sustainable method for resource recovery,has garnered considerable attention in the context of WWTB disposal.This work presents a comprehensive review of the pyrolytic recycling of WWTB,focusing on the principles and classifications of pyrolysis technology,key factors influencing the pyrolysis process,as well as the pyrolysis methods,equipment,products,and their applications.Through an in-depth analysis of the current research on the pyrolytic recycling of WWTB,this review identifies critical unresolved issues in the field and provides a forward-looking perspective on emerging research trends.
基金supported by the Yunnan Province Basic Research General Program,China(No.202201BE070001-002)the Major Science and Technology Projects in Yunnan Province,China(No.202402AF 080005).
文摘The rapid expansion of the photovoltaic industry has generated heavily oxidized waste silicon(wSi),which hinders efficient recycling owing to its small particle size and uncontrolled surface oxidation.This study introduces a molten salt electrochemical strategy for converting photovoltaic wSi into NiSi_(2)-silicon nanorods(NiSi_(2)-SiNRs)as high-performance anode materials for lithium-ion batteries.A stable oxidized passivation layer is formed on the wSi surface via controlled oxidation,and further in situ generated highly active NiSi_(2) droplets.The molten salt electric field modulates the surface energy of silicon,while particle integration drives localized directional growth,enabling the self-assembly of NiSi_(2)-SiNRs composites.These NiSi_(2)-SiNRs anodes exhibit rapid ion transport and effective strain buffering.The high aspect ratio of SiNRs and the presence of retained NiSi_(2) facilitate both longitudinal and transverse Li^(+) diffusion.Owing to their robust structural design,the NiSi_(2)-SiNRs anode achieves an excellent initial Coulombic efficiency of 91.61%and retains 72.99%of its capacity after 800 cycles at 2 A·g^(−1).This study establishes a model system for investigating silicide/silicon interfaces in molten salt electrochemical synthesis and provides an effective strategy for upcycling photovoltaic wSi into high-performance lithium-ion battery anodes.
基金Project supported by the Natural National Science Foundation of China(21707167)。
文摘Red mud is a byproduct of alumina refining of bauxite ores,and is a significant source for extracting scandium.However,a large amount of iron in red mud makes it difficult to recover scandium because Fe(III) and Sc(Ⅲ) have similar physicochemical properties.In this study,a new method was developed for selective separation of iron and scandium in acid leachate of red mud using D201 resin.Theoretical calculations indicate that the ferric species mainly exists as FeCl3 or FeCl4-at chloride concentration above 6.65 mol/L,while scandium still exists as SCl2+,making it possible to selectively separate iron fro m scandium through anion resin adso rption.The factors affecting the adso rption of iron and scandium such as chloride conce ntratio n,resin dosage,adso rption time,and temperature were evaluated in batch experiments,The Langmuir model was successfully applied to both iron and scandium adsorption,and the maximum adsorption capacities of iron and scandium are 147.06 and 0.95 mg/g,respectively,indicating a significant difference between iron and scandium.Raman analysis further demonstrates that the iron is adsorbed onto D201 resin as FeCl4 anion.
基金supported by the Fundamental Research Funds for the Central Universities(No.20822041B4013)Key Laboratory of Development and Application of Rural Renewable Energy,Ministry of Agriculture and Rural Affairs,China(No.18H0491)。
文摘A vacuum membrane distillation(VMD)process with permeate fractional condensation on membrane downstream has been developed for simultaneous recovery of phosphorus and nitrogen from liquid digestate.The polytetrafluoroethylene(PTFE)membrane flux could reach 6000 g·m-2·h-1 with the rejection efficiency of total phosphorus(TP)over 0.99,under the condition of flowrate being 120 L·h-1 and temperature being 40°C.Membrane fouling occurred with a film of organics and microorganism deposited on the surface of the membrane.Membrane flux could be reversed after the membrane was rinsed by water.Higher feed temperature and flowrate could improve the membrane flux,while hardly affect the rejection efficiency of total phosphorus.The concentration of TP could reach 1600 mg·L-1 after membrane distillation,which is about 5 times of that in initial liquid digestate.On the downstream of the membrane,some of the permeate vapor was condensed under the vacuum condition and most of water was collected here.The remaining vapor enriched with total nitrogen(TN)was compressed and pumped to the atmospheric condition to condense.The TN concentration in atmospheric condensate was as high as 7000 mg·L-1 with the process separation factor for ammonia being enhanced to 114.
文摘Based on the principle of bacterial leaching and bacterial metallurgy,a novel technology for the detoxification of chromium-containing slag by Achromobacter sp.CH-1 and chromium recovery was proposed.Strain CH-1 cell morphology before and after Cr(Ⅵ) reduction was observed with a scanning electron microscope(SEM),and the reduction product is found to adhere to terminals of CH-1 cells.Energy-dispersive X-ray(EDX) and electron paramagnetic resonance(EPR) analyses reveal that the main component of the reduction product is Cr(Ⅲ).Furthermore,small and large-scale demonstration projects reveal that Achromobacter sp.can be used to detoxify chromium-containing slag and to selectively recover chromium by using this novel technique.Chromium recovery rate increases with decreasing particle sizes of chromium-containing slag and slagheap height.Chromium recovery rates in 10 t/batch and 20 t/batch of on-site demonstration projects for chromium-containing slag detoxification are more than 90%.
文摘Recovery of Ni-Cd batteries was studied by a self-designed vacuum-aided recovering system under laboratory conditions. The fundamental research on a process of disassembling and recovering selected materials from Ni-Cd batterieswas conducted. The impacts of temperature, pressure and time were studied respectively. The mechanism of vacuum thermal recovering was also discussed. The results show that: Ni-Cd batteries can be recovered effectively byvacuum-aided recovering system at 573~1173 K. At constant pressure, the increase of temperature can improve theseparating efficiency of cadmium. When the temperature is 1173 K, the cadmium can evaporate completely fromthe residue during 3 h at 10 Pa. The reduction of pressure in the certain range is effective to separate cadmium byvacuum distillation. Distillation time is a very important factor affecting separation of cadmium.
基金financially supported by the National Natural Science Foundation of China(No.22206080)Zhongyuan Yingcai Jihua(No.ZYYCYU202012183)+11 种基金Henan Key Scientific Research Projects(No.23B610004)Henan Postdoctoral Foundation(No.202003027)the Natural Science Youth Fund of Henan Province(Nos.202300410034 and 232300420336)the Natural Science Foundation of Jiangsu(No.SBK2022041070)the Science and Technology Project of Henan Province(No.232102321050)the International Science and Technology Cooperation Projects of Henan Province(No.232102521009)the Young Teacher Foundation of Henan University of Urban Construction(No.YCJQNGGJS202306)China Postdoctoral Science Foundation(No.2021M701099)the Academic Leader of Henan Institute of Urban Construction(No.YCJXSJSDTR202204)the Science and Technology Major Special of Pingdingshan(No.2021ZD03)the Key University Scientific Research Project of Henan Province(No.22A610007)the Doctoral Research Start-up Project of Henan University of Urban Construction(No.990/K-Q2022016)。
文摘UiO-66 series metal-organic framework materials(MOFs)are typical porous materials assembled by Zr^(4+) with a large mass-to-nucleus ratio and terephthalic acid ligands,which form tetrahedral and octahedral cages arranged in a periodic triangular window pattern.Due to the strong interaction between Zr and O,UiO-66 series MOFs exhibit high thermal stability,structural stability,and chemical stability.This article mainly reviews the applications of UiO-66 and its composites in adsorption,photocatalysis,and resource utilization,while exploring the harm of pollutants to human health and the environment.In the first part,the differences in adsorption and removal mechanisms of liquid organic pollutants,heavy metals,and volatile organic compounds(VOCs)are investigated.The results show that organic pollutants are mainly removed by physical adsorption,electrostatic interactions,hydrogen bonding,andπ-πinteractions,while heavy metals are mainly removed by chemical adsorption,electrostatic interactions,reduction,and chelation.VOCs are mainly removed by the pore volume and pore size structure of the material.Heterojunction catalysis can achieve non-toxic treatment of pollutants,and this study mainly focuses on UiO-based composite materials constructed by strategies such as semiconductor composites,ion doping,and metal/dye encapsulation.In the second part,the synergistic effect between the components of UiO-based composite materials promotes the oriented and rapid separation and transfer of earriers at the material interface,thereby promoting the generation of active species such as h^(+),·O_(2)^(-) and·OH,and achieving rapid degradation of pollutants and detoxification of heavy metals.In the third part,heterojunctions can realize the resource utilization of pollutants in water and air,producing energy-type substances such as hydrogen and methanol while solving environmental problems.In addition,this article also summarizes the harm of common typical pollutants to the environment and human health.Finally,the development prospects and unresolved problems of UiO-66-based materials in water remediation,gas purification,and environmental resource utilization are reviewed.
文摘One of the major problems of agricultural soils in the tropical regions of the Pacific is the low organic matter content.Because of the hot and humid environment,the soil organic matter(SOM)is minimal due to rapid decomposition.Composted organic material is being applied on agricultural fields as an amendment to provide nutrients and enhance the organic matter content for improving the physical and chemical properties of the cultivated soils.In addition land application of composted material as a fertilizer source effectively disposes of wastes that otherwise are buried in landfills.In our soil program at the University of Guam,we are evaluating the use of organic material as an alternative to synthetic fertilizers.Its goal is to develop management strategies and use available resources for improving crop production while conserving resources and preserving environmental quality.Our case study project is designed to improve soil fertility status by using composted organic wastes and assessing how the nitrogen and other essential nutrients contribute to long-term soil fertility and crop productivity without application of synthetic fertilizers.In our pilot project,compost is produced from wood chips,grinded typhoon debris mixed with animal manure,fish feed,shredded paper and other organic wastes.Mature compost is then applied on the field at the rates of 0,5,10 and 20 t/ha as a soil amendment on the eroded cobbly soils of southern Guam.Corn is planted and monitored for growth performance and yield.The effect of land application of composted material on the SOM content and overall soil quality indices are being evaluated in this pilot study.
文摘At present, in the process of rural environmental treatment, the garbage problem has become the main problem that currently affects the rural environmental pollution. In view of this problem, the relevant departments should adopt effective solutions to classify the rural solid garbage, and at the same time, recycle the valuable garbage for secondary treatment. At present, the garbage in the rural areas of China mainly comes from domestic garbage, livestock breeding waste, agricultural straw and other solid wastes. Aiming at the problems existing in the treatment process of the above pollutants, in-depth research and discussion are carried out to obtain valuable recyclable remediation plan.
基金supported by the National Natural Science Foundation of China(52125001,52370033,and 31970106).
文摘Wastewater treatment significantly contributes to greenhouse gas emissions,which are further exacerbated by the environmental impact of external chemical additions.In response,microbial electrochemical wastewater refining has gained prominence at the interdisciplinary frontier of wastewater resource recovery and green bio-manufacturing.Significant progress has been made in utilizing active electrodes to stimulate CO_(2) fixation rates,applying“binary electron donors”to produce high-value-added chemicals,and developing novel processes and equipment.This review explores various aspects of microbial electrochemical wastewater refining,including microbial electrochemical monitoring of water quality,chemical synthesis from diverse carbon sources,and the deployment of pilot-scale systems for generating electricity,hydrogen,and methane,as well as for in-situ remediation.Additionally,it discusses the challenges and future directions,highlighting the importance of understanding mechanisms,advancing electrocatalyst and microbial engineering,and innovating hybrid processes.In conclusion,the widespread adoption of microbial electrochemical wastewater refining is emphasized for resource recovery and sustainable chemical production,ultimately reducing environmental impact.
基金support from the National Natural Science Foundation of China(grant nos.12205009,12375336,and U20B2019).
文摘The efficient recovery of rhenium(Re),a scarce metal closely associated with the energy and aerospace industries,is essential for alleviating global Re resource tension.For the first time,we propose a radiosensitization reduction method to selectively reclaim ReO_(4)^(−) as ReO_(2) from its aqueous solutions,utilizing a stable Hf-based metal–organic framework,Hf-BPY,as an effective radiation sensitizer.While interacting withγ-rays or electron beams(EBs),Hf-BPY provides Hf6-cluster arrays with high atomic number,exhibiting radiation attenuation ability that enhances the radiolysis of water,which further increases the yield of reductive hydrated electrons(eaq^(−))from 2.80×10^(−7) to 4.05×10^(−7) mol/J.As a clean reduction method,the reaction is propelled directly by the enriched eaq^(−),without the need for any sacrificial agents.Pure ReO_(2) is obtained with resistance to reoxidation and redissolution.This laboratory-proven approach is further scaled up to liter scale,achieving the recovery of 0.568 and 0.468 g/L of ReO_(2) usingγ-ray and EB irradiation,respectively.Along with its cyclic ability to maintain a stable reduction ratio over seven radiation cycles,this approach holds great potential for industrial Re recovery.The feasibility of radiosensitization reduction for the decontamination of heavy metal pollution is further confirmed,adding to the evidence of its prospects for broad application.
基金supported by the National Research Foundation of Korea(NRF)funded by the Ministry of Science and Information and Communication Technology(ICT)(NRF-2020M3H4A3106354)Korea Government(MSIT,RS-2023-00213022)the Korea Institution of Science and Technology(KIST)internal projects.
文摘The photochemical conversion of plastic waste into valuable resources under ambient conditions is challenging.Achieving efficient photocatalytic conversion necessitates intimate contact between the photocatalyst and plastic substrate,as water molecules are readily oxidized by photogenerated holes,potentially bypassing the plastic as the electron donor.This study demonstrated a novel strategy for depositing polystyrene(PS)waste onto a photoanode by leveraging its solubility in specific organic solvents,including acetone and chloroform,thus enhancing the interface contact.We used an anodization technique to fabricate a skeleton-like porous tungsten oxide(WO_(3))structure,which exhibited higher durability against detachment from a conductive substrate than the WO_(3) photoanode fabricated using the doctor blade method.Upon illumination,the photogenerated holes were transferred from WO_(3) to PS,promoting the oxidative degradation of plastic waste under ambient conditions.Consequently,the oxidative degradation of PS on the anode side generated carbon dioxide,while the cathodic process produced hydrogen gas through water reduction.Our findings pave the way for sunlight-driven plastic waste treatment technologies that concurrently generate valuable fuels or chemicals and offer the dual benefits of cost savings and environmental protection.
基金supporting the research project under the USK Leading Research Program-Doctoral Acceleration Scheme(PRRU-PD,Grant Number:444/UN11.2.1/PG.01.03/SPK/PTNBH/2024)coordinated by the Institute for Research and Community Services(LPPM-USK).
文摘As the world’s largest palm oil producer,Indonesia significantly benefits from its palm oil industry but also faces serious environmental challenges from palm oil mill effluent(POME)-a high-strength wastewater containing substantial organic matter,nutrients,suspended solids,and various chemical compounds.Sustainable and effective wastewater treatment strategies are urgently needed to address this issue.This review presents a comprehensive analysis of existing POME treatment technologies,including anaerobic digestion(AD),advanced oxidation processes(AOPs),membrane filtration,adsorption,phytoremediation,and microalgae-based systems.Each method is examined in terms of treatment efficiency,operational feasibility,and potential for imple-mentation under Indonesian conditions.While advanced processes,such as AOPs and membrane filtration,achieve high pollutant removal,they are often limited by operational costs.In contrast,biological approaches,such as AD and phytoremediation,offer both environmental benefits and economic value through the recovery of biogas,biofertilizers,and biomass.This review highlights the potential for integrating wastewater purification with resource recovery and valorization,supporting a shift toward more circular and sustainable management of POME.The insights provided are intended to guide future research,inform policy decisions,and facilitate the industrial adoption of optimized treatment systems.
基金supported by National Natural Science Foundation of China(Nos.22176012,51878023)BUCEA Post Graduate Innovation Project(No.PG2023057)BUCEA Doctor Graduate Scientific Research Ability Improvement Project(No.DG2024022)。
文摘The nano-MOF-303 synthesized by microwave method exhibited efficient adsorption capacity(232 mg/g)toward Ag^(+),in which the adsorption behaviors were fitted by the pseudo-second-order kinetic and the Freundlich isotherm model.The outstanding Ag^(+)sorption ability of nano-MOF-303 could be contributed to electrostatic interactions,weak coordination interaction of Ag-N,and Ag Cl precipitates originating from the stored Cl^(-)in nano-MOF-303.Besides the adsorbent regeneration,the formed Ag/Ag Cl onto nano-MOF-303 could produce Ag/Ag Cl/MOF-303 as a photocatalyst for sulfamethoxazole degradation under visible light.In this work,both the adsorption and photocatalysis mechanisms were clarified,which might provide insight to develop more effective adsorbents for mining the critical resource from the wastewater.
基金supported by the Joint Research Program for Ecological Conservation and High Quality Development of the Yellow River Basin(No.2022-YRUC-01-0203).
文摘Urine consists of approximately 95%water,3.5%organic matter,and 1.5%inorganic salts.Membrane distillation(MD)offers a potential approach for urine resource utilization.To some extent,it reduces the loss of nitrogen and phosphorus resources.However,MD is also accompanied by problems such as high membrane cost,membrane fouling and membrane wetting.In light of these issues,this study employs polytetrafluoroethylene(PTFE)as the separation layer and polypropylene(PP)as the support layer to make a distillation membrane.The feasibility and efficiency of the PTFE-PP membrane in intercepting and recovering nitrogen and phosphorus from source-separated urine were investigated.Results obtained through 14 days of continuous operation demonstrated that the recovery rates of nitrogen and phosphorus were 95%and 99%,respectively.The dissolved organic carbon recovery rate was 95%,and urea as well as the macromolecular organic matter in dissolved organic matter were significantly intercepted.The phosphorus content in the permeate was 0.022 mg/L,which met theⅡclass standard of China’s surface water and the basic water use standard of the United States Environmental Protection Agency.This finding reduces the pressure on sewage treatment plants.PTFE-PP distillation membrane has important potential in recovering nitrogen and phosphorus from urine and alleviating global water shortage.
基金Project(51104073) supported by the National Natural Science Foundation of China
文摘Traditional treatments of zinc dross have many disadvantages,such as complicated recovering process and serious environmental pollution.In this work,a new process of chlorine removal from zinc dross by microwave was proposed for solving problem of recycling the zinc dross.With better ability of absorbing the microwave than zinc oxide,the main material in zinc dross,chlorides,can be heated and evaporated rapidly during microwave roasting.Various parameters including roasting temperature,duration time and stirring speed were optimized.The microstructure of roasted materials was characterized by X-ray diffraction(XRD) and scanning electron microscope(SEM).The content of the chloride was analyzed by the method of chlorine ion selective electrode.The experiments indicate that the best duration time is 60 min with a stirring speed of 15 r/min during the microwave roasting process.The dechlorination rate reaches peak value of 88% at 700 ℃.The chlorine is removed as HCl gas when water vapor is used as activating agent,which means that it can be recovered into hydrochloride acid.
基金supported by the National Natural Science Foundation of China“Behavioral Experiment and Policy Research of Pig Farmers when Diseased Dead Pigs Entering the Market”[Gant number 71540008]the Key Projects of National Natural Science Foundation of China“Experimental Assessment of Agricultural Producer Safety Production Policy and Its Combined Design:Taking the Treatment of Diseased Dead Pigs as an Example”[Grant number 71673115]+3 种基金the Fundamental Research Funds for the Central Universities“Food Safety Risk Management Logic and Realistic Path Based on Big Data”[Grant number.JUSRP1808ZD]the National College Student Innovation Training Program[grant number.201810295025]the National Key R&D Program Funding Project[Grant number.2018YFC1603303]the National Key R&D Program Funding Project[Grant number.2018YFC1604000].
文摘Based on field research data on farmers in 30 counties(districts)of six cities in Shandong Province,this study systematically examines the methods of disposal of livestock and poultry waste and the factors that influence them,that is,the determinants of farmers’waste disposal behaviors,using the UTAUT theoretical framework and a disordered multi-class logit model.The results show that,first,economic performance expectancy,subjective norms,farming population,and poultry and livestock breeding numbers have significant effects on the four waste recycling methods considered:direct return,compost fermentation,biogas fermentation,and fresh-packed sale.Second,annual family income has a positive effect on the direct return method.Third,compost fermentation is positively affected by farmers'knowledge,distance from sources of water,and farming scale,and negatively affected by gender and marital status.Fourth,biogas fermentation is negatively affected by the age of farmers and positively affected by the farming income ratio and environmental convenience.Finally,the most important factors affecting the four methods are subjective norms,farming scale,economic performance expectancy,and farming population.Therefore,this study proposes that policies to promote resource utilization of livestock and poultry waste must prioritize raising awareness among the farmers of the advantages of resource disposal of waste;provide reasonable subsidies for waste recycling and enhance policy applicability,pertinence,and motivation;strengthen the promotion of waste recycling technology and improve the practicality of lectures or training content;and improve relevant laws and regulations and enhance authority and usability.
文摘Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining technology for residual coal of end slopes.In the proposal a conveyance road and ventilation conveyance near the slope are built,corresponding to the pit mining area and the surface coal mine dump,as well as an interval haulage tunnel and air-inlet tunnel.The outcome shows that such mining method may reduce the effect to slope stability from underground mining,it does not affect the dumping advance and has a high recovery rate of residual coal resources.The working face is timbered by single hydraulic props,transported by a scraper conveyor and supported by coal walls.This method of mining is one of layered top coal caving,with high resource recovery,low production cost where positive economic benefit can be realized.
