Polyvinylpyrrolidone-reduced graphene oxide was prepared by modified hummers method and was used as adsorbent for removing Cu ions from wastewater. The effects of contact time and ions concentration on adsorption capa...Polyvinylpyrrolidone-reduced graphene oxide was prepared by modified hummers method and was used as adsorbent for removing Cu ions from wastewater. The effects of contact time and ions concentration on adsorption capacity were examined. The maximum adsorption capacity of 1689 mg/g was observed at an initial p H value of 3.5 after agitating for 10 min. It was demonstrated that polyvinylpyrrolidone-reduced graphene oxide had a huge adsorption capacity for Cu ions, which was 10 times higher than maximal value reported in previous works. The adsorption mechanism was also discussed by density functional theory. It demonstrates that Cu ions are attracted to surface of reduced graphene oxide by C atoms in reduced graphene oxide modified by polyvinylpyrrolidone through physisorption processes, which may be responsible for the higher adsorption capacity. Our results suggest that polyvinylpyrrolidone-reduced graphene oxide is an effective adsorbent for removing Cu ions in wastewater. It also provides a new way to improve the adsorption capacity of reduced graphene oxide for dealing with the heavy metal ion in wastewater.展开更多
With the rapid development of textile industry,a large amount of dye-contaminated effluents was produced and caused serious environmental problem.To remove the dye from effluents,adsorption materials have been applied...With the rapid development of textile industry,a large amount of dye-contaminated effluents was produced and caused serious environmental problem.To remove the dye from effluents,adsorption materials have been applied because of their relatively cheap,high efficiency,and easy handling.In this study,a novel composite hydrogel bead with unique multilayer flake structure was fabricated by alginate,acrylamide and attapulgite for dye adsorption.Acrylamide was grafted polymerization onto alginate to obtain alginate-g-poly(acrylamide).Then alginate-g-poly(acrylamide)was cross-linked by Ca2+ions in present of attapulgite to form composite hydrogel bead.Scanning electron microscopy(SEM)results show that the freeze dried composite hydrogel bead has multilayer flake structure incorporating attapulgite.Fourier transform infrared spectroscopy(FTIR)and Thermo-gravimetric analysis(TGA)results indicate that acrylamide has been successfully grafted polymerization on sodium alginate.Grafting polymerization of acrylamide onto sodium alginate obviously enhances the swelling of hydrogel bead.Incorporating of attapulgite into hydrogel bead effectively enhances the adsorption capacity to methylene blue and the maximum adsorption capacity is 155.7 mg g-1.Multilayer flake structure increases the adsorption area for methylene blue,but hinders the diffusion of methylene blue into the inner of composite hydrogel bead.High pH solution is beneficial to the adsorption.Pseudo-second order model and Fraundlinch model best describe the adsorption kinetic and isotherm,respectively.These results indicate that composite hydrogel bead is a promising adsorption material for dye-contaminated water treatment.展开更多
First-principles calculations based on density functional theory are used to investigate the adsorptions and diffusions of carbon atoms on the surface and in the subsurface of Co （200）. The preferred site for the ca...First-principles calculations based on density functional theory are used to investigate the adsorptions and diffusions of carbon atoms on the surface and in the subsurface of Co （200）. The preferred site for the carbon atom on the surface is the hollow site, and the preferred site in the subsurface is the octahedral site. There is charge transfer from the surface to the adsorbed carbon atom, and for the most favorable adsorbed structure the charge transfer is largest. Moreover, the energy barriers for the diffusions of carbon atoms on the surface and from the surface into the subsurface and then back to the surface are calculated in detail. The results indicate that the energy barrier for the diffusion of carbon atoms on the surface is comparable to that from the subsurface to the surface. The results imply that both the direct surface nucleation and the surface segregation from Co bulk can be observed in the chemical vapor deposition growth of graphene on Co （200） substrate, which can gain a new insight into the growth mechanism of graphene.展开更多
We investigate the adsorptions of Ar on Al （111） and Ir （111） surfaces at the four high symmetry sites, i.e., top, bridge, fcc- and hcp-hollow sites at the coverage of 0.25 monolayer （ML） using the density funct...We investigate the adsorptions of Ar on Al （111） and Ir （111） surfaces at the four high symmetry sites, i.e., top, bridge, fcc- and hcp-hollow sites at the coverage of 0.25 monolayer （ML） using the density functional theory within the generalized gradient approximation of Perdew, Burke and Ernzerhof functions. The geometric structures, the binding energies, the electronic properties of argon atoms adsorbed on Al （111） and Ir （111） surfaces, the difference in electron density between on the Al （111） surface and on the Ir （111） surface and the total density of states are calculated. Our studies indicate that the most stable adsorption site of Ar on the Al （111） surface is found to be the fcc-hollow site for the （2 x 2） structure. The corresponding binding energy of an argon atom at this site is 0.538 eV/Ar atom at a coverage of 0.25 ML. For the Ar adsorption on Ir （111） surface at the same coverage, the most favourable site is the hcp-hollow site, with a corresponding binding energy of 0.493 eV. The total density of states （TDOS） is analysed for Ar adsorption on Al （111） surface and it is concluded that the adsorption behaviour is dominated by the interaction between 3s, 3p orbits of Ar atom and the 3p orbit of the base Al metal and the formation of sp hybrid orbital. For Ar adsorption on Ir （111） surface, the conclusion is that the main interaction in the process of Ar adsorption on Ir （111） surface comes from the 3s and 3p orbits of argon atom and 5d orbit of Ir atom.展开更多
Black Arsenic-phosphorus(AsP)monolayer is a novel two-dimensional nanomaterial with the characteristics of modest direct bandgap and superhigh carrier mobility.However,little is known about how the surface adsorption ...Black Arsenic-phosphorus(AsP)monolayer is a novel two-dimensional nanomaterial with the characteristics of modest direct bandgap and superhigh carrier mobility.However,little is known about how the surface adsorption affects the property of AsP monolayer.Motivated by this,we researched systematically the geometry,adsorption energy,magnetic moment and electronic structure of 11 different adatoms adsorbed on AsP monolayer using firstprinciples calculations.The adatoms used in this study include light nonmetallic(C,N,O)adatoms,period-3 metal(Na,Mg,Al)adatoms,and transition-metal(Ti,V,Cr,Mn,and Fe)adatoms.The adatoms cause an abundant variety of structural,magnetic and electronic properties.This study shows that AsP binds strongly with all adatoms under study and the adsorption energies in all systems are much stronger than that on graphene,Si C,BN,or MoS2.The semiconductor property of AsP is affected by the introduction of adsorbed atoms,which can induce mid-gap states or cause n-type doping.Moreover,the adatom adsorptions cause various spintronic characteristics:N-,Ti-,and Fe-adsorbed AsP become bipolar semiconductors,while the Mn-decorated AsP becomes a bipolar spin-gapless semiconductor.Our results suggest that atomic adsorption on AsP monolayers has potential application in the field of nanoelectronics and spintronics.展开更多
The adsorptive denitrification performance of MIL-101(Cr)-0.5 toward pyridine,aniline or quinoline in simulated fuels with basic nitrogen content of 1732μg/g was evaluated separately.Furthermore,the effects of adsorp...The adsorptive denitrification performance of MIL-101(Cr)-0.5 toward pyridine,aniline or quinoline in simulated fuels with basic nitrogen content of 1732μg/g was evaluated separately.Furthermore,the effects of adsorption temperature,adsorption time and adsorbent dosage on their adsorptive denitrification performance were systematically investigated.The experimental results demonstrated that under a fixed adsorbent dosage of 0.05 g and a simulated fuel volume of 10 mL,the optimal removal efficiency for aniline was achieved at 30℃ within 30 min,whereas higher temperatures and longer times(40℃and 40 min)were required for effective removal of pyridine and quinoline.Density Functional Theory(DFT)calculations were conducted via Materials Studio(MS)software to study the adsorptive denitrification mechanism of MIL-101(Cr)toward these three basic nitrogen-containing compounds.The simulation calculation results revealed that the interaction between pyridine and MIL-101(Cr)primarily involved coordination adsorption.In contrast,the interaction between aniline or quinoline and MIL-101(Cr)proceeded mainly through coordination,with additional contributions fromπ-complexation and hydrogen bonding.The overall adsorption strength order is pyridine>aniline>quinoline.During the adsorption process,pyridine and quinoline transfer electrons to the MIL-101(Cr)surface through the H→C→N→Cr^(3+)pathway,while aniline transfers electrons to the MIL-101(Cr)surface through various pathways,including N→Cr^(3+),N→C→Cr^(3+)and N→H→O.Furthermore,adsorption kinetics studies indicated that the adsorption processes for all three basic nitrogen-containing compounds followed the quasi second order kinetic models.The experimental results on the effect of benzene on the adsorptive denitrification performance of MIL-101(Cr)-0.5 demonstrated that benzene exerted a more significant impact on the adsorption of aniline and quinoline.Finally,the adsorbent was regenerated using ethanol washing.It was found that MIL-101(Cr)-0.5 retained stable denitrification performance after two regeneration cycles.展开更多
A metal-organic framework/inorganic composite(ZIF-8@AMP)was synthesized by the in situ introduction of the active component ammonium phosphomolybdate(AMP)during the ambient solution-phase synthesis of the metal-organi...A metal-organic framework/inorganic composite(ZIF-8@AMP)was synthesized by the in situ introduction of the active component ammonium phosphomolybdate(AMP)during the ambient solution-phase synthesis of the metal-organic framework(ZIF-8).The structure and properties of the composite were characterized using scanning electron microscopy(SEM),X-ray powder diffraction(XRD),X-ray photoelectron spectroscopy(XPS),thermogravimetric analysis(TGA),and Fourier transform infrared spectroscopy(FTIR).Its adsorption performance for Rb^(+)and Cs^(+)in water was investigated.Results indicate that ZIF-8@AMP exhibited adsorption efficiencies of 93.5%and 95.6%for Rb^(+)and Cs^(+)within 30 min,with maximum adsorption capacities of 92.7 and 104.5 mg·g^(-1),respectively.After five adsorption-desorption cycles,it maintained high adsorption capacity and achieved over 84.9%adsorption efficiency for Rb^(+)and Cs^(+)in actual brine samples.The adsorption of ZIF-8@AMP for Rb^(+)and Cs^(+)follows pseudosecond-order kinetics and the Langmuir adsorption isotherm,indicating an endothermic,entropy-increasing,and spontaneous process.The adsorption mechanism involves electrostatic attraction and ion exchange between ZIF-8@AMP and Rb^(+)and Cs^(+).展开更多
In this study,a nickel-based MOF{(NH_(2)(CH_(3))_(2))_(2)[Ni_(3)(O)(L)3(NH(CH_(3))_(2))_(3)]}_(n)(Ni_(3)-MOF),with pore sizes of approximately 1.6 nm×1.6 nm,was synthesized by reacting 4,4′-biphenyldicarboxylic ...In this study,a nickel-based MOF{(NH_(2)(CH_(3))_(2))_(2)[Ni_(3)(O)(L)3(NH(CH_(3))_(2))_(3)]}_(n)(Ni_(3)-MOF),with pore sizes of approximately 1.6 nm×1.6 nm,was synthesized by reacting 4,4′-biphenyldicarboxylic acid(H_(2)L)with Ni(NO_(3))_(2)·6H_(2)O in an N,N-dimethylformamide(DMF)solution.The nanoscale adsorbent Ni_(3)-MOF-N with a particle diameter of approximately 200 nm was prepared using Ni_(3)-MOF.It exhibited a maximum equilibrium tetracycline(TC)adsorption capacity of 358.2 mg·g^(-1)at its isoelectric point(pH=6.50),outperforming most reported MOF-based adsorbents.This exceptional performance is likely attributed to the well-matched pore size of Ni_(3)-MOF-N(1.6 nm×1.6 nm)and the molecular dimensions of TC(0.8 nm×1.2 nm),combined with the presence of partial Ni(Ⅱ)sites on the surface of Ni_(3)-MOF-N.These features collectively facilitate effective TC adsorption through a combination of pore filling,electrostatic attraction,hydrogen bonding,surface complexation,andπ-πinteractions.Recycling experiments demonstrated that Ni_(3)-MOF-N possesses excellent structural stability and consistent adsorption performance.CCDC:2481791,Ni_(3)-MOF.展开更多
CO_(2) capture and utilization(CCU)technologies have been recognized as crucial strategies for mitigating global warming,reducing carbon emission,and promoting resource circularity.As such,the design and development o...CO_(2) capture and utilization(CCU)technologies have been recognized as crucial strategies for mitigating global warming,reducing carbon emission,and promoting resource circularity.As such,the design and development of related materials have attracted considerable research attention.Carbon-based materials,characterized by tunable pore structures,abundant active sites,high specific surface area,and excellent chemical stability,demonstrate significant potential for applications in CO_(2) capture and utilization.This review systematically analyzes the adsorption behaviors and performance variations of typical carbon materials,including activated carbon,porous carbon,graphene,and carbon nanotubes during CO_(2) capture processes.Concerning CO_(2) utilization,emphasis is placed on recent advances in the catalytic applications of carbon-based materials in key reactions such as methanation,reverse water-gas shift,dry reforming of methane,and alcohol synthesis.Moreover,the benefits and drawbacks of carbon materials in terms of CO_(2) adsorption capacity,catalytic activity,and stability are thoroughly evaluated,and their potential applications in integrated CO_(2) capture and utilization technologies are discussed.Finally,key strategies for enhancing the performance of carbonaceous materials through structural modulation and surface modification are elucidated.This review aims to provide theoretical guidance for the future development and large-scale implementation of carbon-based materials in CCU technologies.展开更多
Density functional theory(DFT)has helped propel the advance of electrocatalysis in the past two decades.In view of its massive use,it is worth asking how reliable DFT is for the prediction of adsorption energies,which...Density functional theory(DFT)has helped propel the advance of electrocatalysis in the past two decades.In view of its massive use,it is worth asking how reliable DFT is for the prediction of adsorption energies,which are paramount in computational electrocatalysis models.Here,we provide an experimental-computational approach to break down overall adsorption-energy errors into separate gas-phase and adsorbed-phase contributions.The method is evaluated using experimental data and various exchange-correlation functionals and materials for C-and O-containing species.Our main conclusion is that no functional is simultaneously accurate for adsorbates and molecules,as adsorbed-phase errors are visibly different from gas-phase errors.Importantly,total,gas-phase,and adsorbed-phase errors are correlated,revealing intrinsic DFT limitations and enabling the elaboration of swift correction routines.To illustrate the benefits of our approach,we deconvolute and correct all errors in CO_(2)electroreduction to CO and find an agreement with experiments close to chemical accuracy for numerous transition-metal electrodes and all scrutinized functionals.展开更多
To meet the needs of the treatment of Cu^(2+)pollution in aqueous solution,the sodium alginate-modified polyacrylic acid(PAA/SA)composite hydrogel was prepared by solution polymerization with acrylic acid(AA)as monome...To meet the needs of the treatment of Cu^(2+)pollution in aqueous solution,the sodium alginate-modified polyacrylic acid(PAA/SA)composite hydrogel was prepared by solution polymerization with acrylic acid(AA)as monomer,sodium alginate(SA)as filler,N,N’-methylenebisacrylamide(MBA)as crosslinking agent,and potassium persulfate(K2S2O8)as initiator.The characterization results showed that the introduction of SA significantly improved the physical and chemical properties of PAA hydrogel materials.Scanning electron microscopy(SEM)showed that as the SA content increased,the materials gradually evolved from a dense blocky structure to a porous network.When the SA content was 10 wt%,it exhibited a fragmented layered morphology.The Brunauer Emmett Teller(BET)showed that the specific surface area reached 37.65 m2/g and the porosity increased to 12.47%.Fourier transform infrared(FTIR)spectroscopy confirmed that SA was successfully embedded into the PAA network through hydrogen bonding and ion crosslinking,and the carboxyl vibration peak shifted from 2378 to 2352 cm^(-1).Mechanical tests showed that at 10 wt%SA,the maximum stress was 13.1 kPa.The adsorption experiment showed that the equilibrium adsorption capacity of the PAA/SA hydrogel for Cu^(2+)was 11.03 mg/g,with an adsorption efficiency of 42.65%.Dynamics studies showed that the adsorption process follows a first-order kinetic model(R2=0.986-0.997),indicating a physical adsorption mechanism dominated by liquid film diffusion.Theoptimal process conditions were found to be a dosage of 1.5 g/L,and the effect of temperature on adsorption was limited.The material maintained 67.4%of its initial adsorption capacity after six adsorption-desorption cycles.These parameters are generally superior to those of similar materials reported in the literature,indicating broad application prospects.Such a kinetic and isotherm model resulted from the combined effects of functional groups,electrostatic attraction,and chelation.In practical applications,pH,ionic strength,and competing ions will affect the adsorption performance of PAA/SA composite hydrogels.展开更多
FAU zeolites have emerged as multifunctional materials with broad applications in catalysis and adsorption,owing to their hierarchical pore architectures,elevated specific surface areas,and adjustable extra-framework ...FAU zeolites have emerged as multifunctional materials with broad applications in catalysis and adsorption,owing to their hierarchical pore architectures,elevated specific surface areas,and adjustable extra-framework cationic sites.This review provides a critical overview of recent advances in FAU zeolite research with emphasis on their roles in environmental pollutant mitigation.A bibliometric analysis was performed to ascertain worldwide research trends,cooperation networks,and principal theme areas.Strategies for synthesis and functionalization,including crystallization pathways,one-pot methods,and post-synthetic modifications,were systematically evaluated for their capacity to tailor structural and physicochemical properties.Environmental applications were discussed in detail,particularly in heavy metal extraction,CO_(2)capture,and catalytic NOx reduction.Despite these advances,challenges persisted,notably restricted chemical stability under extreme pH conditions,scalability obstacles from laboratory to industrial production,and the necessity for enhanced catalytic efficiency.By integrating fundamental understanding with application-oriented perspectives,this review identifies existing knowledge gaps and delineates future directions for the rational design of FAU zeolites toward sustainable environmental remediation.展开更多
To efficiently remove radioactive nuclides from nuclear industry wastewater and minimize the generation of radioactive secondary waste,this study proposes the concept of a magnetically controlled microchannel adsorber...To efficiently remove radioactive nuclides from nuclear industry wastewater and minimize the generation of radioactive secondary waste,this study proposes the concept of a magnetically controlled microchannel adsorber based on magnetic adsorbents.A novel protocol for achieving high adsorption performance in microchannel adsorbers with periodically distributed particles is developed using the particle-resolved computational fluid dynamics (CFD) method,which addresses the limitations of traditional porous media flow models.To align simulation results more closely with practical scenarios,a typical high-efficiency magnetic adsorbent,magnetic sodium alginate/cobalt-based Prussian blue (M-SA/PB-Co),was synthesized.The M-SA/PB-Co microspheres exhibit a uniform size distribution (300–600 μm),and their Cs^(+) adsorption follows the pseudo-second-order kinetic model with a Langmuir saturated adsorption capacity of 124.84 mg·g^(-1).The performance parameters of M-SA/PB-Co,obtained from characterization and adsorption experiments,were integrated into CFD simulations.CFD results indicate that as the flow velocity increases,the flow field gradually transitions with vortices expanding in scale and streamline bifurcation points shifting rearward.The Cs^(+) concentration decreases progressively along the flow direction,with a more pronounced reduction in the vortex regions downstream of particles.The characteristic velocity and characteristic concentration of specific regions surrounding the particles were extracted based on boundary layer distribution.The amount of concentration reduction of Cs^(+) through particle is positively correlated with the characteristic concentration and negatively correlated with the characteristic velocity.The number of microspheres required in the microchannel adsorber was optimized using the response surface method.Compared with industrial fixed-bed adsorbers,microchannel adsorbers exhibit 8–10 times higher processing capacity,demonstrating significant industrial application potential.展开更多
A novel layered cobalt–magnesium double hydroxide composite(L-CMs)was successfully prepared using a simple onestep co-precipitation method.Static adsorption experiments were conducted to examine the removal efficacy ...A novel layered cobalt–magnesium double hydroxide composite(L-CMs)was successfully prepared using a simple onestep co-precipitation method.Static adsorption experiments were conducted to examine the removal efficacy of U(Ⅵ)from aqueous solutions by the L-CMs and analyze the removal mechanism.L-CMs efficiently removed U(Ⅵ)from the aqueous solution under an adsorption time of 60 min,dosage of 0.4 g/L,and pH of 5.5 at room temperature,and the removal efficiency of U(Ⅵ)reached 94.59%with an initial U(Ⅵ)concentration of 10 mg/L.The adsorption process was fitted to the pseudosecond-order kinetic and Langmuir models,indicating that monolayer chemical adsorption occurred primarily.The maximum adsorption capacity fitted using the Langmuir model was 105.49 mg/g.Thermodynamic analysis revealed that U(Ⅵ)adsorption by L-CMs was endothermic.Structural characterization results showed that the primary mechanism involved the complexation of U(Ⅵ)by–OH,CO_(3)^(2-)and ion exchange by Mg^(2+)and the presence of layered Co(OH)_(2) in the L-CMs,which potentially facilitated ion exchange.The preparation of the composite materials was simple,and the synergistic effect between the materials enhanced the ion exchange of Mg^(2+)in the materials and enriched the content of functional groups,making it a potential candidate for the treatment of uranium-containing wastewater.展开更多
Economical and sustainable wastewater treatment techniques are highly demanded to alleviate the issues of clearwater scarcity globally.In this work,the acetic acid/H_(2)O_(2) (AHP) was leveraged to enrich oxygenated f...Economical and sustainable wastewater treatment techniques are highly demanded to alleviate the issues of clearwater scarcity globally.In this work,the acetic acid/H_(2)O_(2) (AHP) was leveraged to enrich oxygenated functional groups on the biochar surface for efficient ciprofloxacin (CIP) adsorption and biochar regeneration (In situ degradation of CIP in the spent AHP solution).The AHP-modified biochar exhibited significantly enhanced CIP adsorption capacity,about 22 times that of the pristine biochar.The optimized modification condition (acetic acid/H_(2)O_(2):2.11,temperature:45 ℃,and time:12 h) was screened by the response surface method,reaching the highest CIP adsorption capacity of 86.26 mg·g^(−1).Characterization results revealed that the content of carboxyl —C=O—O was enhanced in AHP-modified biochar,which contributed to efficient CIP adsorption by the electrostatic interaction,hydrogen bonding,and hydrophobic interaction.The adsorption of modified biochar to CIP molecules was a spontaneous endothermic process,and in line with the pseudo-second-order model and the Langmuir isotherm model.Moreover,the biochar modification process enabled the spent AHP solution with a strong oxidizing agent of peracetic acid (PAA),which can be employed to degrade adsorbed CIP for biochar in-situ generation.This work tailored a closed-loop strategy for biochar oxidation,contaminant adsorption,and biochar regeneration,highlighting a viable route for sustainable wastewater treatment.展开更多
Flubendiamide is a commonly used pesticide with low water solubility and a high organic carbon sorption constant,causing it to adhere to soil particles and negatively impact soil ecosystems.First,chili plant stems,typ...Flubendiamide is a commonly used pesticide with low water solubility and a high organic carbon sorption constant,causing it to adhere to soil particles and negatively impact soil ecosystems.First,chili plant stems,typically discarded after the harvest season,represent an abundant local biomass resource with significant potential for utilization,and were converted into biochar through pyrolysis.Here,we describe the synthesis of biochar modified with iron and chitosan to increase the diversity of functions and surface functional groups of biochar.The resulting chitosan-modified magnetic biochar(CMBC)presents a full range of functional groups of chitosan and iron oxide as shown by Fourier-transform infrared spectroscopy.The correlation between flubendiamide concentration and the dose of biochar on adsorption was explored.The flubendiamide adsorption efficiency of CMBC(1%mass ratio of soil)reached 68.03%in 90 min.The highest adsorption capacity achieved was 0.95 mg·g^(−1).The flubendiamide adsorption mechanism by CMBC can be described with a pseudo-second-order kinetic model.The experiment data closely fit a Freundlich isotherm model(R^(2)=0.998),and the low residual sum of squares values demonstrate the high model applicability.In this study,we present a comprehensive overview of pesticides,alongside kinetic and isotherm model studies of flubendiamide adsorption by CMBC.We emphasize the potential of modified biochar to enhance environmental remediation applications.展开更多
A novel macroparticle magnesium-modified biochar/yttrium alginate(Mg-BC/SA-Y)hybrid biogel composite was successfully developed through a facile solution reaction of magnesium-modified BC and yttrium alginate polymer,...A novel macroparticle magnesium-modified biochar/yttrium alginate(Mg-BC/SA-Y)hybrid biogel composite was successfully developed through a facile solution reaction of magnesium-modified BC and yttrium alginate polymer,and its properties were characterized.The obtained Mg-BC/SA-Y biogel beads have a particle size of approximately 1.5 mm,featuring abundant network pores and an uneven,distinctive surface.The performance and mechanisms of Mg-BC/SA-Y for phosphate adsorption were thoroughly investigated.The findings indicate that Mg-BC/SA-Y removes up to 95.7%of phosphate at pH4.0 and 298 K,and also achieves a phosphate removal efficiency of over 80%within a pH range of3.0-11.0.The adsorption capacity of Mg-BC/SA-Y for phosphate is nearly four times that of BC.The spontaneous adsorption processes and endothermic adsorption behavior can be elucidated by the pseudo-second-order rate and Langmuir equations,respectively.Phosphate adsorption is almost unaffected by water ionic strength and common coexisting ions,except for the influence of highconcentration F-ions.The recyclable biogel beads can be reused after adsorbing phosphate,and represent excellent stability and practicability in real water.The mechanisms of ligand exchange,innersphere complexation and electrostatic attraction are involved in phosphate removal.Mg-BC/SA-Y biogel polymer is a desirable and sustainable biosorbent for treating water with excessive phosphate levels and reducing pollution and carbon emissions.展开更多
Antibiotics,as an emerging pollutant due to their extensive use and difficulty in biodegradation,can cause harm to health through bioaccumulation.To address this,various photocatalysts have been developed for rapid an...Antibiotics,as an emerging pollutant due to their extensive use and difficulty in biodegradation,can cause harm to health through bioaccumulation.To address this,various photocatalysts have been developed for rapid antibiotic removal.However,their low concentrations limit mass transfer efficiency,resulting in suboptimal performance.Adsorption is crucial for enhancing photocatalytic efficiency.In this study,a series of binary heterojunction catalysts(x%BWO@STHP)were synthesized,consisting of Bi_(2)WO_(6)(BWO)grafted with sulfonated triptycene-based hypercrosslinked polymer(STHP).The high specific surface area of STHP,combined withπ-πconjugation and ionic interactions with antibiotics,significantly enhances adsorption capacity.This facilitates effective contact between low-concentration pollutants in aqueous solutions and the active sites of the catalyst.The formation of a Z-scheme heterojunction between BWO and STHP facilitates photogenerated charge separation,and further significantly improves photocatalytic degradation performance.Specifically,the 20%BWO@STHP catalyst achieved rapid adsorption equilibrium for oxytetracycline(OTC),doxycycline(DOX),and tetracycline(TC)within 2 min and completely degraded them after 15 min of irradiation.Compared to pristine BWO,the photocatalytic reaction rate constants are significantly increased,being 9.69 times higher for OTC and 13.45 times higher for DOX.The catalyst exhibits excellent reusability and holds promising potential for practical applications.展开更多
In this study,chitosan(CS)was combined with microcrystalline cellulose(MCC)to fabricate composite hydrogel beads.These beads were further modified through blending and grafting with polyethyleneimine(PEI)to develop ch...In this study,chitosan(CS)was combined with microcrystalline cellulose(MCC)to fabricate composite hydrogel beads.These beads were further modified through blending and grafting with polyethyleneimine(PEI)to develop chitosan/microcrystalline cellulose@polyethyleneimine(CS/MCC@PEI)composite gel spheres for the efficient adsorption of diclofenac sodium(DS)from aqueous solutions.The adsorbent was characterized using scanning electron microscopy(SEM),X-ray diffraction(XRD),Fourier-transform infrared spectroscopy(FTIR),X-ray pho-toelectron spectroscopy(XPS),and thermogravimetric analysis(TGA).The CS/MCC@PEI composite exhibited a spherical morphology with a porous structure,abundant surface functional groups,and a high adsorption capac-ity of 274.84 mg/g for DS.Kinetic studies revealed that the adsorption process followed the pseudo-second-order model,dominated by physical adsorption,with both surface and internal diffusion influencing the adsorption rate.The Freundlich isotherm model best described the adsorption behavior,indicating multilayer adsorption on heterogeneous surfaces.Environmental adaptability tests demonstrated minimal interference from co-existing anions and humic acid,while regeneration experiments confirmed excellent reusability(>77%removal after five cycles).The adsorption mechanism involved electrostatic interactions and hydrogen bonding between the hydroxyl/amino groups of the composite and DS.These findings highlight the potential of CS/MCC@PEI as a cost-effective and sustainable adsorbent for DS removal from water.展开更多
基金the support by National Natural Science Foundation of China under grants (11202006)University’s Science and technology exploiture of Shangxi Province (20121010)the National Basic Research Program of China (G2010CB832701)
文摘Polyvinylpyrrolidone-reduced graphene oxide was prepared by modified hummers method and was used as adsorbent for removing Cu ions from wastewater. The effects of contact time and ions concentration on adsorption capacity were examined. The maximum adsorption capacity of 1689 mg/g was observed at an initial p H value of 3.5 after agitating for 10 min. It was demonstrated that polyvinylpyrrolidone-reduced graphene oxide had a huge adsorption capacity for Cu ions, which was 10 times higher than maximal value reported in previous works. The adsorption mechanism was also discussed by density functional theory. It demonstrates that Cu ions are attracted to surface of reduced graphene oxide by C atoms in reduced graphene oxide modified by polyvinylpyrrolidone through physisorption processes, which may be responsible for the higher adsorption capacity. Our results suggest that polyvinylpyrrolidone-reduced graphene oxide is an effective adsorbent for removing Cu ions in wastewater. It also provides a new way to improve the adsorption capacity of reduced graphene oxide for dealing with the heavy metal ion in wastewater.
基金for Doctors of Jinling Institute of Technology(Grant No.jit-b-201415)the Natural Science Foundation for Colleges and Universities of Jiangsu Province(Grant No.12KJD150006)for the financial support of this research.
文摘With the rapid development of textile industry,a large amount of dye-contaminated effluents was produced and caused serious environmental problem.To remove the dye from effluents,adsorption materials have been applied because of their relatively cheap,high efficiency,and easy handling.In this study,a novel composite hydrogel bead with unique multilayer flake structure was fabricated by alginate,acrylamide and attapulgite for dye adsorption.Acrylamide was grafted polymerization onto alginate to obtain alginate-g-poly(acrylamide).Then alginate-g-poly(acrylamide)was cross-linked by Ca2+ions in present of attapulgite to form composite hydrogel bead.Scanning electron microscopy(SEM)results show that the freeze dried composite hydrogel bead has multilayer flake structure incorporating attapulgite.Fourier transform infrared spectroscopy(FTIR)and Thermo-gravimetric analysis(TGA)results indicate that acrylamide has been successfully grafted polymerization on sodium alginate.Grafting polymerization of acrylamide onto sodium alginate obviously enhances the swelling of hydrogel bead.Incorporating of attapulgite into hydrogel bead effectively enhances the adsorption capacity to methylene blue and the maximum adsorption capacity is 155.7 mg g-1.Multilayer flake structure increases the adsorption area for methylene blue,but hinders the diffusion of methylene blue into the inner of composite hydrogel bead.High pH solution is beneficial to the adsorption.Pseudo-second order model and Fraundlinch model best describe the adsorption kinetic and isotherm,respectively.These results indicate that composite hydrogel bead is a promising adsorption material for dye-contaminated water treatment.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51002014,51202017,and 51372095)the Research Fund for the Doctoral Program of Higher Education of China(Grant No.20120061120039)+2 种基金the Funds from the Science and Technology Department of Jilin Province,China(Grant Nos.20120745 and 20130101029JC)the Funds from the Department of Education of Jilin Province,China(Grant No.2013279)the Youth Science Research Foundation of Liaoning University,China(Grant No.2013LDQN20)
文摘First-principles calculations based on density functional theory are used to investigate the adsorptions and diffusions of carbon atoms on the surface and in the subsurface of Co （200）. The preferred site for the carbon atom on the surface is the hollow site, and the preferred site in the subsurface is the octahedral site. There is charge transfer from the surface to the adsorbed carbon atom, and for the most favorable adsorbed structure the charge transfer is largest. Moreover, the energy barriers for the diffusions of carbon atoms on the surface and from the surface into the subsurface and then back to the surface are calculated in detail. The results indicate that the energy barrier for the diffusion of carbon atoms on the surface is comparable to that from the subsurface to the surface. The results imply that both the direct surface nucleation and the surface segregation from Co bulk can be observed in the chemical vapor deposition growth of graphene on Co （200） substrate, which can gain a new insight into the growth mechanism of graphene.
基金supported by the National Natural Science Foundation of China (Grant No.11074176 and 10976019)the Doctoral Program of Higher Education of China (Grant No.20100181110080)
文摘We investigate the adsorptions of Ar on Al （111） and Ir （111） surfaces at the four high symmetry sites, i.e., top, bridge, fcc- and hcp-hollow sites at the coverage of 0.25 monolayer （ML） using the density functional theory within the generalized gradient approximation of Perdew, Burke and Ernzerhof functions. The geometric structures, the binding energies, the electronic properties of argon atoms adsorbed on Al （111） and Ir （111） surfaces, the difference in electron density between on the Al （111） surface and on the Ir （111） surface and the total density of states are calculated. Our studies indicate that the most stable adsorption site of Ar on the Al （111） surface is found to be the fcc-hollow site for the （2 x 2） structure. The corresponding binding energy of an argon atom at this site is 0.538 eV/Ar atom at a coverage of 0.25 ML. For the Ar adsorption on Ir （111） surface at the same coverage, the most favourable site is the hcp-hollow site, with a corresponding binding energy of 0.493 eV. The total density of states （TDOS） is analysed for Ar adsorption on Al （111） surface and it is concluded that the adsorption behaviour is dominated by the interaction between 3s, 3p orbits of Ar atom and the 3p orbit of the base Al metal and the formation of sp hybrid orbital. For Ar adsorption on Ir （111） surface, the conclusion is that the main interaction in the process of Ar adsorption on Ir （111） surface comes from the 3s and 3p orbits of argon atom and 5d orbit of Ir atom.
基金supported by the National Natural Science Foundation of China(No.11404268 and No.11774294)the Sichuan Province Applied Science and Technology Project(No.2017JY0056)the R&D Program for International ST Cooperation and Exchanges of Sichuan province(No.2018HH0088)。
文摘Black Arsenic-phosphorus(AsP)monolayer is a novel two-dimensional nanomaterial with the characteristics of modest direct bandgap and superhigh carrier mobility.However,little is known about how the surface adsorption affects the property of AsP monolayer.Motivated by this,we researched systematically the geometry,adsorption energy,magnetic moment and electronic structure of 11 different adatoms adsorbed on AsP monolayer using firstprinciples calculations.The adatoms used in this study include light nonmetallic(C,N,O)adatoms,period-3 metal(Na,Mg,Al)adatoms,and transition-metal(Ti,V,Cr,Mn,and Fe)adatoms.The adatoms cause an abundant variety of structural,magnetic and electronic properties.This study shows that AsP binds strongly with all adatoms under study and the adsorption energies in all systems are much stronger than that on graphene,Si C,BN,or MoS2.The semiconductor property of AsP is affected by the introduction of adsorbed atoms,which can induce mid-gap states or cause n-type doping.Moreover,the adatom adsorptions cause various spintronic characteristics:N-,Ti-,and Fe-adsorbed AsP become bipolar semiconductors,while the Mn-decorated AsP becomes a bipolar spin-gapless semiconductor.Our results suggest that atomic adsorption on AsP monolayers has potential application in the field of nanoelectronics and spintronics.
基金Supported by Basic Scientific Research Project of the Liaoning Provincial Department of Education Has Been Unveiled to Facilitate Local Project Funding (JYTMS20230835)Enhanced Scientific Research Project Funded by the Departmentof Higher Education in Liaoning Province (General program)(JYTMS20230852)。
文摘The adsorptive denitrification performance of MIL-101(Cr)-0.5 toward pyridine,aniline or quinoline in simulated fuels with basic nitrogen content of 1732μg/g was evaluated separately.Furthermore,the effects of adsorption temperature,adsorption time and adsorbent dosage on their adsorptive denitrification performance were systematically investigated.The experimental results demonstrated that under a fixed adsorbent dosage of 0.05 g and a simulated fuel volume of 10 mL,the optimal removal efficiency for aniline was achieved at 30℃ within 30 min,whereas higher temperatures and longer times(40℃and 40 min)were required for effective removal of pyridine and quinoline.Density Functional Theory(DFT)calculations were conducted via Materials Studio(MS)software to study the adsorptive denitrification mechanism of MIL-101(Cr)toward these three basic nitrogen-containing compounds.The simulation calculation results revealed that the interaction between pyridine and MIL-101(Cr)primarily involved coordination adsorption.In contrast,the interaction between aniline or quinoline and MIL-101(Cr)proceeded mainly through coordination,with additional contributions fromπ-complexation and hydrogen bonding.The overall adsorption strength order is pyridine>aniline>quinoline.During the adsorption process,pyridine and quinoline transfer electrons to the MIL-101(Cr)surface through the H→C→N→Cr^(3+)pathway,while aniline transfers electrons to the MIL-101(Cr)surface through various pathways,including N→Cr^(3+),N→C→Cr^(3+)and N→H→O.Furthermore,adsorption kinetics studies indicated that the adsorption processes for all three basic nitrogen-containing compounds followed the quasi second order kinetic models.The experimental results on the effect of benzene on the adsorptive denitrification performance of MIL-101(Cr)-0.5 demonstrated that benzene exerted a more significant impact on the adsorption of aniline and quinoline.Finally,the adsorbent was regenerated using ethanol washing.It was found that MIL-101(Cr)-0.5 retained stable denitrification performance after two regeneration cycles.
文摘A metal-organic framework/inorganic composite(ZIF-8@AMP)was synthesized by the in situ introduction of the active component ammonium phosphomolybdate(AMP)during the ambient solution-phase synthesis of the metal-organic framework(ZIF-8).The structure and properties of the composite were characterized using scanning electron microscopy(SEM),X-ray powder diffraction(XRD),X-ray photoelectron spectroscopy(XPS),thermogravimetric analysis(TGA),and Fourier transform infrared spectroscopy(FTIR).Its adsorption performance for Rb^(+)and Cs^(+)in water was investigated.Results indicate that ZIF-8@AMP exhibited adsorption efficiencies of 93.5%and 95.6%for Rb^(+)and Cs^(+)within 30 min,with maximum adsorption capacities of 92.7 and 104.5 mg·g^(-1),respectively.After five adsorption-desorption cycles,it maintained high adsorption capacity and achieved over 84.9%adsorption efficiency for Rb^(+)and Cs^(+)in actual brine samples.The adsorption of ZIF-8@AMP for Rb^(+)and Cs^(+)follows pseudosecond-order kinetics and the Langmuir adsorption isotherm,indicating an endothermic,entropy-increasing,and spontaneous process.The adsorption mechanism involves electrostatic attraction and ion exchange between ZIF-8@AMP and Rb^(+)and Cs^(+).
文摘In this study,a nickel-based MOF{(NH_(2)(CH_(3))_(2))_(2)[Ni_(3)(O)(L)3(NH(CH_(3))_(2))_(3)]}_(n)(Ni_(3)-MOF),with pore sizes of approximately 1.6 nm×1.6 nm,was synthesized by reacting 4,4′-biphenyldicarboxylic acid(H_(2)L)with Ni(NO_(3))_(2)·6H_(2)O in an N,N-dimethylformamide(DMF)solution.The nanoscale adsorbent Ni_(3)-MOF-N with a particle diameter of approximately 200 nm was prepared using Ni_(3)-MOF.It exhibited a maximum equilibrium tetracycline(TC)adsorption capacity of 358.2 mg·g^(-1)at its isoelectric point(pH=6.50),outperforming most reported MOF-based adsorbents.This exceptional performance is likely attributed to the well-matched pore size of Ni_(3)-MOF-N(1.6 nm×1.6 nm)and the molecular dimensions of TC(0.8 nm×1.2 nm),combined with the presence of partial Ni(Ⅱ)sites on the surface of Ni_(3)-MOF-N.These features collectively facilitate effective TC adsorption through a combination of pore filling,electrostatic attraction,hydrogen bonding,surface complexation,andπ-πinteractions.Recycling experiments demonstrated that Ni_(3)-MOF-N possesses excellent structural stability and consistent adsorption performance.CCDC:2481791,Ni_(3)-MOF.
基金Supported by National Key R&D Program of China(2025YFE0109700)the National Natural Science Foundation of China(52106150)。
文摘CO_(2) capture and utilization(CCU)technologies have been recognized as crucial strategies for mitigating global warming,reducing carbon emission,and promoting resource circularity.As such,the design and development of related materials have attracted considerable research attention.Carbon-based materials,characterized by tunable pore structures,abundant active sites,high specific surface area,and excellent chemical stability,demonstrate significant potential for applications in CO_(2) capture and utilization.This review systematically analyzes the adsorption behaviors and performance variations of typical carbon materials,including activated carbon,porous carbon,graphene,and carbon nanotubes during CO_(2) capture processes.Concerning CO_(2) utilization,emphasis is placed on recent advances in the catalytic applications of carbon-based materials in key reactions such as methanation,reverse water-gas shift,dry reforming of methane,and alcohol synthesis.Moreover,the benefits and drawbacks of carbon materials in terms of CO_(2) adsorption capacity,catalytic activity,and stability are thoroughly evaluated,and their potential applications in integrated CO_(2) capture and utilization technologies are discussed.Finally,key strategies for enhancing the performance of carbonaceous materials through structural modulation and surface modification are elucidated.This review aims to provide theoretical guidance for the future development and large-scale implementation of carbon-based materials in CCU technologies.
基金financial support from MICIU/AEI/10.13039/501100011033by the European Union,and grant MOE-T2EP10222-0007 from the Ministry of Education,Singapore。
文摘Density functional theory(DFT)has helped propel the advance of electrocatalysis in the past two decades.In view of its massive use,it is worth asking how reliable DFT is for the prediction of adsorption energies,which are paramount in computational electrocatalysis models.Here,we provide an experimental-computational approach to break down overall adsorption-energy errors into separate gas-phase and adsorbed-phase contributions.The method is evaluated using experimental data and various exchange-correlation functionals and materials for C-and O-containing species.Our main conclusion is that no functional is simultaneously accurate for adsorbates and molecules,as adsorbed-phase errors are visibly different from gas-phase errors.Importantly,total,gas-phase,and adsorbed-phase errors are correlated,revealing intrinsic DFT limitations and enabling the elaboration of swift correction routines.To illustrate the benefits of our approach,we deconvolute and correct all errors in CO_(2)electroreduction to CO and find an agreement with experiments close to chemical accuracy for numerous transition-metal electrodes and all scrutinized functionals.
基金funded by Quality Engineering Project Fund of Anhui University of Applied Technology,grant numbers 2024xjjxyjy41 and 2024xjjpkc05.
文摘To meet the needs of the treatment of Cu^(2+)pollution in aqueous solution,the sodium alginate-modified polyacrylic acid(PAA/SA)composite hydrogel was prepared by solution polymerization with acrylic acid(AA)as monomer,sodium alginate(SA)as filler,N,N’-methylenebisacrylamide(MBA)as crosslinking agent,and potassium persulfate(K2S2O8)as initiator.The characterization results showed that the introduction of SA significantly improved the physical and chemical properties of PAA hydrogel materials.Scanning electron microscopy(SEM)showed that as the SA content increased,the materials gradually evolved from a dense blocky structure to a porous network.When the SA content was 10 wt%,it exhibited a fragmented layered morphology.The Brunauer Emmett Teller(BET)showed that the specific surface area reached 37.65 m2/g and the porosity increased to 12.47%.Fourier transform infrared(FTIR)spectroscopy confirmed that SA was successfully embedded into the PAA network through hydrogen bonding and ion crosslinking,and the carboxyl vibration peak shifted from 2378 to 2352 cm^(-1).Mechanical tests showed that at 10 wt%SA,the maximum stress was 13.1 kPa.The adsorption experiment showed that the equilibrium adsorption capacity of the PAA/SA hydrogel for Cu^(2+)was 11.03 mg/g,with an adsorption efficiency of 42.65%.Dynamics studies showed that the adsorption process follows a first-order kinetic model(R2=0.986-0.997),indicating a physical adsorption mechanism dominated by liquid film diffusion.Theoptimal process conditions were found to be a dosage of 1.5 g/L,and the effect of temperature on adsorption was limited.The material maintained 67.4%of its initial adsorption capacity after six adsorption-desorption cycles.These parameters are generally superior to those of similar materials reported in the literature,indicating broad application prospects.Such a kinetic and isotherm model resulted from the combined effects of functional groups,electrostatic attraction,and chelation.In practical applications,pH,ionic strength,and competing ions will affect the adsorption performance of PAA/SA composite hydrogels.
基金supported by foundation of Guizhou Provincial Basic Research Program Natural Sciencel Youth Guidance Project(No.QN[2025]090)Special post of Guizhou University(No.[2024]20).
文摘FAU zeolites have emerged as multifunctional materials with broad applications in catalysis and adsorption,owing to their hierarchical pore architectures,elevated specific surface areas,and adjustable extra-framework cationic sites.This review provides a critical overview of recent advances in FAU zeolite research with emphasis on their roles in environmental pollutant mitigation.A bibliometric analysis was performed to ascertain worldwide research trends,cooperation networks,and principal theme areas.Strategies for synthesis and functionalization,including crystallization pathways,one-pot methods,and post-synthetic modifications,were systematically evaluated for their capacity to tailor structural and physicochemical properties.Environmental applications were discussed in detail,particularly in heavy metal extraction,CO_(2)capture,and catalytic NOx reduction.Despite these advances,challenges persisted,notably restricted chemical stability under extreme pH conditions,scalability obstacles from laboratory to industrial production,and the necessity for enhanced catalytic efficiency.By integrating fundamental understanding with application-oriented perspectives,this review identifies existing knowledge gaps and delineates future directions for the rational design of FAU zeolites toward sustainable environmental remediation.
基金Dalian distinguished young scholars program(2022RJ17)the Dalian excellent young talents program(2023RY037)provided funding for this study.
文摘To efficiently remove radioactive nuclides from nuclear industry wastewater and minimize the generation of radioactive secondary waste,this study proposes the concept of a magnetically controlled microchannel adsorber based on magnetic adsorbents.A novel protocol for achieving high adsorption performance in microchannel adsorbers with periodically distributed particles is developed using the particle-resolved computational fluid dynamics (CFD) method,which addresses the limitations of traditional porous media flow models.To align simulation results more closely with practical scenarios,a typical high-efficiency magnetic adsorbent,magnetic sodium alginate/cobalt-based Prussian blue (M-SA/PB-Co),was synthesized.The M-SA/PB-Co microspheres exhibit a uniform size distribution (300–600 μm),and their Cs^(+) adsorption follows the pseudo-second-order kinetic model with a Langmuir saturated adsorption capacity of 124.84 mg·g^(-1).The performance parameters of M-SA/PB-Co,obtained from characterization and adsorption experiments,were integrated into CFD simulations.CFD results indicate that as the flow velocity increases,the flow field gradually transitions with vortices expanding in scale and streamline bifurcation points shifting rearward.The Cs^(+) concentration decreases progressively along the flow direction,with a more pronounced reduction in the vortex regions downstream of particles.The characteristic velocity and characteristic concentration of specific regions surrounding the particles were extracted based on boundary layer distribution.The amount of concentration reduction of Cs^(+) through particle is positively correlated with the characteristic concentration and negatively correlated with the characteristic velocity.The number of microspheres required in the microchannel adsorber was optimized using the response surface method.Compared with industrial fixed-bed adsorbers,microchannel adsorbers exhibit 8–10 times higher processing capacity,demonstrating significant industrial application potential.
基金financially supported by the National Natural Science Foundation of China(Nos.22266003,22006013,12005037)Academic and Technical Leaders of Major Disciplines in Jiangxi Province(20225BCJ23020)Graduate Science and Technology Innovation Project of Jiangxi Province(YC2023-S563)。
文摘A novel layered cobalt–magnesium double hydroxide composite(L-CMs)was successfully prepared using a simple onestep co-precipitation method.Static adsorption experiments were conducted to examine the removal efficacy of U(Ⅵ)from aqueous solutions by the L-CMs and analyze the removal mechanism.L-CMs efficiently removed U(Ⅵ)from the aqueous solution under an adsorption time of 60 min,dosage of 0.4 g/L,and pH of 5.5 at room temperature,and the removal efficiency of U(Ⅵ)reached 94.59%with an initial U(Ⅵ)concentration of 10 mg/L.The adsorption process was fitted to the pseudosecond-order kinetic and Langmuir models,indicating that monolayer chemical adsorption occurred primarily.The maximum adsorption capacity fitted using the Langmuir model was 105.49 mg/g.Thermodynamic analysis revealed that U(Ⅵ)adsorption by L-CMs was endothermic.Structural characterization results showed that the primary mechanism involved the complexation of U(Ⅵ)by–OH,CO_(3)^(2-)and ion exchange by Mg^(2+)and the presence of layered Co(OH)_(2) in the L-CMs,which potentially facilitated ion exchange.The preparation of the composite materials was simple,and the synergistic effect between the materials enhanced the ion exchange of Mg^(2+)in the materials and enriched the content of functional groups,making it a potential candidate for the treatment of uranium-containing wastewater.
基金supported by the National Natural Science Foundation of China(22478266 and 32472027)the National Key Research&Development Program of China(2022YFE0207100)the Department of Science and Technology of Sichuan Province(2024ZYD0080 and 2022YFN0027).
文摘Economical and sustainable wastewater treatment techniques are highly demanded to alleviate the issues of clearwater scarcity globally.In this work,the acetic acid/H_(2)O_(2) (AHP) was leveraged to enrich oxygenated functional groups on the biochar surface for efficient ciprofloxacin (CIP) adsorption and biochar regeneration (In situ degradation of CIP in the spent AHP solution).The AHP-modified biochar exhibited significantly enhanced CIP adsorption capacity,about 22 times that of the pristine biochar.The optimized modification condition (acetic acid/H_(2)O_(2):2.11,temperature:45 ℃,and time:12 h) was screened by the response surface method,reaching the highest CIP adsorption capacity of 86.26 mg·g^(−1).Characterization results revealed that the content of carboxyl —C=O—O was enhanced in AHP-modified biochar,which contributed to efficient CIP adsorption by the electrostatic interaction,hydrogen bonding,and hydrophobic interaction.The adsorption of modified biochar to CIP molecules was a spontaneous endothermic process,and in line with the pseudo-second-order model and the Langmuir isotherm model.Moreover,the biochar modification process enabled the spent AHP solution with a strong oxidizing agent of peracetic acid (PAA),which can be employed to degrade adsorbed CIP for biochar in-situ generation.This work tailored a closed-loop strategy for biochar oxidation,contaminant adsorption,and biochar regeneration,highlighting a viable route for sustainable wastewater treatment.
基金supported by research funds of Jeonbuk National University in 2024 and partly supported by the National Research Foundation of Korea(NRF-2019R1A2C1006441)from the Ministry of Education.
文摘Flubendiamide is a commonly used pesticide with low water solubility and a high organic carbon sorption constant,causing it to adhere to soil particles and negatively impact soil ecosystems.First,chili plant stems,typically discarded after the harvest season,represent an abundant local biomass resource with significant potential for utilization,and were converted into biochar through pyrolysis.Here,we describe the synthesis of biochar modified with iron and chitosan to increase the diversity of functions and surface functional groups of biochar.The resulting chitosan-modified magnetic biochar(CMBC)presents a full range of functional groups of chitosan and iron oxide as shown by Fourier-transform infrared spectroscopy.The correlation between flubendiamide concentration and the dose of biochar on adsorption was explored.The flubendiamide adsorption efficiency of CMBC(1%mass ratio of soil)reached 68.03%in 90 min.The highest adsorption capacity achieved was 0.95 mg·g^(−1).The flubendiamide adsorption mechanism by CMBC can be described with a pseudo-second-order kinetic model.The experiment data closely fit a Freundlich isotherm model(R^(2)=0.998),and the low residual sum of squares values demonstrate the high model applicability.In this study,we present a comprehensive overview of pesticides,alongside kinetic and isotherm model studies of flubendiamide adsorption by CMBC.We emphasize the potential of modified biochar to enhance environmental remediation applications.
基金Project supported by the National Natural Science Foundation of China(21167011)the Natural Science Foundation of Inner Mongolia Autonomous Region,China(2020LH02009)the Collaborative Innovation Center for Water Environment Security of Inner Mongolia Autonomous Region,China(XTCX003)。
文摘A novel macroparticle magnesium-modified biochar/yttrium alginate(Mg-BC/SA-Y)hybrid biogel composite was successfully developed through a facile solution reaction of magnesium-modified BC and yttrium alginate polymer,and its properties were characterized.The obtained Mg-BC/SA-Y biogel beads have a particle size of approximately 1.5 mm,featuring abundant network pores and an uneven,distinctive surface.The performance and mechanisms of Mg-BC/SA-Y for phosphate adsorption were thoroughly investigated.The findings indicate that Mg-BC/SA-Y removes up to 95.7%of phosphate at pH4.0 and 298 K,and also achieves a phosphate removal efficiency of over 80%within a pH range of3.0-11.0.The adsorption capacity of Mg-BC/SA-Y for phosphate is nearly four times that of BC.The spontaneous adsorption processes and endothermic adsorption behavior can be elucidated by the pseudo-second-order rate and Langmuir equations,respectively.Phosphate adsorption is almost unaffected by water ionic strength and common coexisting ions,except for the influence of highconcentration F-ions.The recyclable biogel beads can be reused after adsorbing phosphate,and represent excellent stability and practicability in real water.The mechanisms of ligand exchange,innersphere complexation and electrostatic attraction are involved in phosphate removal.Mg-BC/SA-Y biogel polymer is a desirable and sustainable biosorbent for treating water with excessive phosphate levels and reducing pollution and carbon emissions.
基金the financial support provided by the National Natural Science Foundation of China(22478267,22438009,U24A20535)Basic Research Program of Jiangsu province(BK20243002)+1 种基金Prospective Application Research Project of Suzhou(SYC2022042)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Antibiotics,as an emerging pollutant due to their extensive use and difficulty in biodegradation,can cause harm to health through bioaccumulation.To address this,various photocatalysts have been developed for rapid antibiotic removal.However,their low concentrations limit mass transfer efficiency,resulting in suboptimal performance.Adsorption is crucial for enhancing photocatalytic efficiency.In this study,a series of binary heterojunction catalysts(x%BWO@STHP)were synthesized,consisting of Bi_(2)WO_(6)(BWO)grafted with sulfonated triptycene-based hypercrosslinked polymer(STHP).The high specific surface area of STHP,combined withπ-πconjugation and ionic interactions with antibiotics,significantly enhances adsorption capacity.This facilitates effective contact between low-concentration pollutants in aqueous solutions and the active sites of the catalyst.The formation of a Z-scheme heterojunction between BWO and STHP facilitates photogenerated charge separation,and further significantly improves photocatalytic degradation performance.Specifically,the 20%BWO@STHP catalyst achieved rapid adsorption equilibrium for oxytetracycline(OTC),doxycycline(DOX),and tetracycline(TC)within 2 min and completely degraded them after 15 min of irradiation.Compared to pristine BWO,the photocatalytic reaction rate constants are significantly increased,being 9.69 times higher for OTC and 13.45 times higher for DOX.The catalyst exhibits excellent reusability and holds promising potential for practical applications.
基金supported by the Open Project Funding of Key Laboratory of Intelligent Health Perception and Ecological Restoration of Rivers and Lakes,Ministry of Education,Hubei University of Technology(No.HGKFZ03).
文摘In this study,chitosan(CS)was combined with microcrystalline cellulose(MCC)to fabricate composite hydrogel beads.These beads were further modified through blending and grafting with polyethyleneimine(PEI)to develop chitosan/microcrystalline cellulose@polyethyleneimine(CS/MCC@PEI)composite gel spheres for the efficient adsorption of diclofenac sodium(DS)from aqueous solutions.The adsorbent was characterized using scanning electron microscopy(SEM),X-ray diffraction(XRD),Fourier-transform infrared spectroscopy(FTIR),X-ray pho-toelectron spectroscopy(XPS),and thermogravimetric analysis(TGA).The CS/MCC@PEI composite exhibited a spherical morphology with a porous structure,abundant surface functional groups,and a high adsorption capac-ity of 274.84 mg/g for DS.Kinetic studies revealed that the adsorption process followed the pseudo-second-order model,dominated by physical adsorption,with both surface and internal diffusion influencing the adsorption rate.The Freundlich isotherm model best described the adsorption behavior,indicating multilayer adsorption on heterogeneous surfaces.Environmental adaptability tests demonstrated minimal interference from co-existing anions and humic acid,while regeneration experiments confirmed excellent reusability(>77%removal after five cycles).The adsorption mechanism involved electrostatic interactions and hydrogen bonding between the hydroxyl/amino groups of the composite and DS.These findings highlight the potential of CS/MCC@PEI as a cost-effective and sustainable adsorbent for DS removal from water.
