Metal hydrides with high hydrogen density provide promising hydrogen storage paths for hydrogen transportation.However,the requirement of highly pure H_(2)for re-hydrogenation limits its wide application.Here,amorphou...Metal hydrides with high hydrogen density provide promising hydrogen storage paths for hydrogen transportation.However,the requirement of highly pure H_(2)for re-hydrogenation limits its wide application.Here,amorphous Al_(2)O_(3)shells(10 nm)were deposited on the surface of highly active hydrogen storage material particles(MgH_(2)-ZrTi)by atomic layer deposition to obtain MgH_(2)-ZrTi@Al_(2)O_(3),which have been demonstrated to be air stable with selective adsorption of H_(2)under a hydrogen atmosphere with different impurities(CH_(4),O_(2),N_(2),and CO_(2)).About 4.79 wt% H_(2)was adsorbed by MgH_(2)-ZrTi@10nmAl_(2)O_(3)at 75℃under 10%CH_(4)+90%H_(2)atmosphere within 3 h with no kinetic or density decay after 5 cycles(~100%capacity retention).Furthermore,about 4 wt%of H_(2)was absorbed by MgH_(2)-ZrTi@10nmAl_(2)O_(3)under 0.1%O_(2)+0.4%N_(2)+99.5%H_(2)and 0.1%CO_(2)+0.4%N_(2)+99.5%H_(2)atmospheres at 100℃within 0.5 h,respectively,demonstrating the selective hydrogen absorption of MgH_(2)-ZrTi@10nmAl_(2)O_(3)in both oxygen-containing and carbon dioxide-containing atmospheres hydrogen atmosphere.The absorption and desorption curves of MgH_(2)-ZrTi@10nmAl_(2)O_(3)with and without absorption in pure hydrogen and then in 21%O_(2)+79%N_(2)for 1 h were found to overlap,further confirming the successful shielding effect of Al_(2)O_(3)shells against O_(2)and N_(2).The MgH_(2)-ZrTi@10nmAl_(2)O_(3)has been demonstrated to be air stable and have excellent selective hydrogen absorption performance under the atmosphere with CH_(4),O_(2),N_(2),and CO_(2).展开更多
The rational design of high-performance CO_(2)adsorbents remains a critical challenge in addressing global carbon emissions,with metal-organic frameworks(MOFs)emerging as promising candidates due to their tunable pore...The rational design of high-performance CO_(2)adsorbents remains a critical challenge in addressing global carbon emissions,with metal-organic frameworks(MOFs)emerging as promising candidates due to their tunable pore environments.However,the lack of systematic guidelines for functional group selection has hindered their practical implementation in carbon capture applications.Here,this gap was addressed by developing a comprehensive design framework through high-throughput computational screening.Through construction of a topology-directed database of 4797,integrating 10 metal centers with 144 functionalized ligands(18 ligands modified by–NH_(2),–NO_(2),–CH_(3),–CF_(3),–SH_(2),–SO_(2),–OH,and–OLi)across 36 topologies,the fundamental structure–property relationships governing CO_(2)capture performance was established.Multi-metric evaluation reveals that–NO_(2),–SO_(2),and–OLi dramatically enhance CO_(2)selectivity over CH_4/N_(2)via selectivity(S_(ads)),working capacity(ΔN),adsorbent performance score(APS),sorbent selection parameter(S_(sp)),and renewability R.Specially,ΔN rises from 2.34(pristine)to 5.91–7.94 mmol g^(-1)and S_(ads)surges from 24.94/40.36 to 121.11/176.87(–NO_(2)),149.94/215.54(–SO_(2)),and 58.64/267.44(–OLi).Besides,the critical trade-off between adsorption strength and renewability demonstrates that enhanced performance comes at the cost of reduced renewability,where stronger CO_(2)affinity(isosteric heat of-29.15,-29.96,and-30.09 for–NO_(2),–SO_(2),and–OLi)compromises renewability(R reduced by -50%).To resolve this trade-off,a novel energy efficiency(η)metric was introduced,which holistically evaluates both adsorption performance(S_(ads),ΔN,APS,S_(sp),and R)and energy inputs(desorption heat,pressure-swing energy,net loss).This leads to the identification of–SO_(2)as the optimal functional group that balances exceptional CO_(2)capture(η=6.17/12.78 for CO_(2)over CH_4/N_(2)),surpassing the second higher of 4.74/8.80 in–CF_(3)and 0.99/2.18 in non-functionalized counterparts.Adopting high-throughput computational screening methods,this work provides both fundamental insights into host–vip interactions in functionalized MOFs and a practical framework for designing next-generation adsorbents,bridging the gap between materials discovery and process engineering considerations in carbon capture technologies.展开更多
Metal ion-imprintedly crosslinked chitosan resin 1 and resin 2 were prepared by theuse of Cu2+ and Ni2+ as template ions and glutaraldehyde as crosslinking agent, respectively.Through investigation on the adsorption c...Metal ion-imprintedly crosslinked chitosan resin 1 and resin 2 were prepared by theuse of Cu2+ and Ni2+ as template ions and glutaraldehyde as crosslinking agent, respectively.Through investigation on the adsorption capacities and binding constants for Cu2+, Ni2+andCo2+ ions on chitosan resins, resin 1 and resin 2 exhibit the adsorption selectivity for themixture solution of 1:1 Cu2+ and Ni2+ ions. The adsorption selectivity of metal ion-imprintedresins for their template ions is much higher than that of uncrosslinked chitosan resin.展开更多
We report a robust pillar-layered metal-organic framework,Zn‑tfbdc‑dabco(tfbdc:tetrafluoroterephthal-ate,dabco:1,4-diazabicyclo[2.2.2]octane),featuring the fluorinated pore environment,for the preferential binding of ...We report a robust pillar-layered metal-organic framework,Zn‑tfbdc‑dabco(tfbdc:tetrafluoroterephthal-ate,dabco:1,4-diazabicyclo[2.2.2]octane),featuring the fluorinated pore environment,for the preferential binding of propane over propylene and thus highly inverse selective separation of propane/propylene mixture.The inverse propane-selective performance of Zn‑tfbdc‑dabco for the propane/propylene separation was validated by single-component gas adsorption isotherms,isosteric enthalpy of adsorption calculations,ideal adsorbed solution theory calculations,along with the breakthrough experiment.The customized fluorinated networks served as a propane-trap to form more interactions with the exposed hydrogen atoms of propane,as unveiled by the simulation studies at the molecular level.With the advantage of inverse propane-selective adsorption behavior,high adsorption capacity,good cycling stability,and low isosteric enthalpy of adsorption,Zn‑tfbdc‑dabco can be a promising candidate adsorbent for the challenging propane/propylene separation to realize one-step purification of the target propylene substance.展开更多
A novel porous coordination polymer,iron naphthalenedicarboxylate Fe（OH）（1,4-NDC）·2H2O is hydrothermally synthesized by the reaction of FeSO4·7H2O and 1,4-naphthalenedicarboxylic acid（1,4-H2NDC） at 150...A novel porous coordination polymer,iron naphthalenedicarboxylate Fe（OH）（1,4-NDC）·2H2O is hydrothermally synthesized by the reaction of FeSO4·7H2O and 1,4-naphthalenedicarboxylic acid（1,4-H2NDC） at 150℃.The compound crystallizes in a tetragonal space group P42/nmc：a=2.1447（4） nm,c=0.68849（14） nm,V=3.1669（11） nm3,Z=8,R=0.0845,wR=0.1829.The crystal structure exhibits a three-dimensional framework which is composed of infinite chains of corner-sharing octahedral Fe（OH）2O4 with 1,4-NDC ligands forming two types of channels with square-shaped cross-sections.The large channels present a cross-section of 0.76 nm×0.76 nm,while the small channels are about 0.30 nm×0.30 nm.No structural transformation occurs after removing the vip water molecules,while a robust structure generates with permanent porosity.The adsorption measurements show that the anhydrous sample of the compound can adsorb CO2 into its pores.The adsorption isotherms for methanol,acetone,tetrahydrofuran and benzene are also measured.展开更多
The AgBr powder was prepared by a hydrothermal method via a reaction of AgNO3 with hexadecyltrimethy ammonium bromide（CTAB）,namely,CTAB-assisted synthesis method.The selective-adsorption ability of the AgBr samples ...The AgBr powder was prepared by a hydrothermal method via a reaction of AgNO3 with hexadecyltrimethy ammonium bromide（CTAB）,namely,CTAB-assisted synthesis method.The selective-adsorption ability of the AgBr samples for the MO was evaluated in a MO and Rhodamine B mixed solution via ultraviolet-visible spectra.Compared with the AgBr sample prepared from NaBr solution,it was found that the AgBr powder synthesized by CTAB-assisted method exhibited high selective-adsorption performance for the MO in the MO-RhB mixed system.After aged for 60 min,the MO could be efficiently removed by CTAB-assisted AgBr powder.Considering the potential wide applications of the selective adsorption,the CTAB-assisted AgBr provides a new and efficient method for the removal of various dyes and is possible to be widely used in industries.展开更多
The effective and environmentally friendly management of oily wastewater,alongside the beneficial conversion of waste biomass,holds paramount importance for environmental conservation,public health,and sustainable soc...The effective and environmentally friendly management of oily wastewater,alongside the beneficial conversion of waste biomass,holds paramount importance for environmental conservation,public health,and sustainable societal progress.In this research,an innovative biomass core-shell bioreactor(CGC@SiO_(2) aerogel) with selective adsorption and degradation properties was developed.The reactor's core is composed of coffee cellulose aerogel,offering a porous framework conducive to microbial colonization while safeguarding microorganisms from adverse external factors.The shell integrates hydrophobic silica enriched with polydimethylsiloxane,which alters the material's hydrophilic properties,enabling it to remain afloat on water for up to 100 days.This superhydrophobic layer maintained a contact angle of 150° even after ten consecutive rubbings.Experimental results indicate that the material performs exceptionally well in oil-water separation,as demonstrated by its success in 9 consecutive oil-water separations.It achieved 99 % selective adsorption,91 % removal,and 46.2 % degradation of a 3 wt.% diesel solution under conditions of 37℃,120 r/min,and pH=7.Additionally,tests assessing environmental tolerance revealed the material's robust adaptability and stability across varying pH levels and temperatures.Compared to traditional hydrophobic and lipophilic materials or free-floating microorganisms,CGC@SiO2 aerogel not only efficiently captures oil pollutants but also degrades them into non-hazardous substances.Combining biodegradation with selective adsorption has shown to be an effective approach for treating oily wastewater,offering significant practical application potential.The low-carbon production of CGC@SiO2aerogel aligns with circular economy principles,underscoring its role in sustainable development.展开更多
Selective extraction of precious metals from urban mines plays a crucial role in mitigating the risk of depletion of precious metal resources and reducing waste pollution.However,a major obstacle in precious metal ext...Selective extraction of precious metals from urban mines plays a crucial role in mitigating the risk of depletion of precious metal resources and reducing waste pollution.However,a major obstacle in precious metal extraction lies in the difficulty of distinguishing the subtle differences in the physicochemical characteristics between them,especially gold and palladium.Herein,a proton-driven separation system was presented for cascade recovery of gold and palladium from waste-printed circuit boards(W-PCBs)leachate using poly(amidoxime)(PAO)hydrogel.This exhibits an ultra-high capacity,extra-fast rate,and excellent selectivity for the extraction of Au(Ⅲ)and Pd(Ⅱ).Notably,the separation of Au(Ⅲ)and Pd(Ⅱ)can be achieved with high selectivity at pH=0,resulting in a remarkable separation factor of k_(Au(Ⅲ)/Pd(Ⅱ))=36.5.This was demonstrated to originate from the differential mechanism of PAO hydrogel for the capture of Au(Ⅲ)and Pd(Ⅱ)under proton-mediated conditions.Drawing inspiration from the mechanism,the proton-driven cascade recovery system demonstrates remarkable efficiency in sequentially recovering 99.92%of gold and 99.05%of palladium from W-PCBs acid leachate.This research opens up a strategy to precisely separate and recover precious metals from e-waste of urban mines.展开更多
A novel Ni（Ⅱ） ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid（AMPS） as a func...A novel Ni（Ⅱ） ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid（AMPS） as a functional monomer for the selective separation of Ni（Ⅱ） from aqueous solution. The sorbent showed good chemical and thermal stability. Kinetics studies indicated that the equilibrium adsorption was achieved within 10 min and the adsorption kinetics fitted well with the pseudo-second-order kinetic model. The maximum adsorption capacity of the ion-imprinted polymer towards Ni（Ⅱ） at the optimal p H of 7.0 was 66.22 mg·g^（-1）. The relative selectivity coefficients of the sorbent were 9.23, 15.71, 14.72 and 20.15 for Ni（Ⅱ）/Co（Ⅱ）, Ni（Ⅱ）/Cu（Ⅱ）, Ni（Ⅱ）/Zn（Ⅱ） and Ni（Ⅱ）/Pb（Ⅱ）, respectively. The adsorption isotherm fitted well with Langmuir isotherm model. The thermodynamic results indicated that the adsorption of Ni（Ⅱ） was a spontaneous and endothermic process. The sorbent showed good reusability evidenced by six cycles of adsorption/desorption experiments. The precision of this method is satisfactory. Thus, the prepared sorbent can be considered as a promising sorbent for selective separation of Ni（Ⅱ） in real water samples.展开更多
A novel silica-supported tert-butyl 2-picolyamino-N-acetate chelating resin (Si-AMPY-1) was successfully synthesized and characterized by elemental analysis, FT-IR, SEM and 13 C CP/MAS NMR. The adsorption behaviors of...A novel silica-supported tert-butyl 2-picolyamino-N-acetate chelating resin (Si-AMPY-1) was successfully synthesized and characterized by elemental analysis, FT-IR, SEM and 13 C CP/MAS NMR. The adsorption behaviors of the Si-AMPY-1 resin for Cu(Ⅱ) and Ni(Ⅱ) were studied with batch and column methods. The batch experiments indicated that the Si-AMPY-1 resin adsorbed Ni(Ⅱ) mainly via physisorption, while adsorbed Cu(II) via chemisorption. The column dynamic breakthrough curves revealed thatthe Si-AMPY-1 resin can efficiently separate Cu(Ⅱ) from the simulated nickel electrolyte before the breakthrough point. Moreover, the concentration of Cu(Ⅱ) in the column effluent was decreased to be less than 3 mg/L within the first 43 BV (bed volumes), and the mass ratio of Cu/Ni was 21:1 in the saturated resin, which completely satisfied the industrial requirements of the nickel electrorefining process. Therefore, it was concluded that the Si-AMPY-1 resin can be a promising candidate for the deep removal of Cu(Ⅱ) from the nickel electrolyte.展开更多
Achieving efficient adsorption and desorption processes by controllably tuning the properties of adsorbents at different technical stages is extremely attractive.However,it is difficult for traditional adsorbents to r...Achieving efficient adsorption and desorption processes by controllably tuning the properties of adsorbents at different technical stages is extremely attractive.However,it is difficult for traditional adsorbents to reach the target because of their fixed active sites.Herein,we report on the fabrication of a smart adsorbent,which was achieved by introducing photoresponsive azobenzene derivatives with cis/trans isomers to Ce-doped mesoporous silica.These photoresponsive groups serve as “molecular switches”by sheltering and exposing active sites,leading to efficient adsorption and desorption.Ce is also doped to provide additional active sites in order to enhance the adsorption performance.The results show that the cis isomers effectively shelter the active sites,leading to the selective adsorption of methylene blue(MB)over brilliant blue(BB),while the trans isomers completely expose the active sites,resulting in the convenient release of the adsorbates.Both selective adsorption and efficient desorption can be realized controllably by these smart adsorbents through photostimulation.Moreover,the performance of the obtained materials is well maintained after five cycles.展开更多
The flotation performances of styrene phosphonic acid（SPA） to synthetic（Ce,La）2O3（REO）, calcium fluorite（CaF2） and fluorapatite（Ca5F（PO4）3） were investigated by flotation tests, flotation of synthetic mixe...The flotation performances of styrene phosphonic acid（SPA） to synthetic（Ce,La）2O3（REO）, calcium fluorite（CaF2） and fluorapatite（Ca5F（PO4）3） were investigated by flotation tests, flotation of synthetic mixed mineral, the surface adsorption capacity and the polarizing microscopy to solve the flotation separation problem of rare earth oxides from roasted concentrate. The flotation test results indicated that compared with CaF2 and Ca5F（PO4）3, SPA exhibited superior collecting performance to direct flotation recovery of REO and floated out above 90% REO at pH 3–6. However, the collecting ability of SPA to CaF2 and Ca5F（PO4）3 was extremely weak and the highest recovery was only 20% at pH 2–11. The flotation of synthetic mixed mineral showed that SPA was a good collector reagent for flotation of synthetic REO at pH 5, so REO, CaF2 and Ca5F（PO4）3 could be separated from roasted concentrate by using SPA as a collector. The surface adsorption capacity tests and polarizing microscopy results confirmed that SPA was adsorbed on REO surface, while CaF2 and Ca5F（PO4）3 were not. The adsorption mechanism of SPA to synthetic REO was studied by solution chemistry analysis of collector, the ζ-potential tests, infrared spectroscopy and X-ray photoelectron spectroscopy（XPS） analyses. The results indicated that SPA was physically adsorbed onto REO surface, which exhibited excellent flotation selectivity to REO against CaF2 and Ca5F（PO4）3.展开更多
Surface modification offers an alternative strategy to improve both ageing resistance and electrochemical performance of cathode materials for lithium-ion batteries.From the viewpoint of real application,surface modif...Surface modification offers an alternative strategy to improve both ageing resistance and electrochemical performance of cathode materials for lithium-ion batteries.From the viewpoint of real application,surface modification of the cathode materials should be designed with scientificity,effectiveness,low cost,less Li+leaching,and remained tap density.In this contribution,a selective adsorption-involved in-situ growth of polyaniline(PANI)nanoparticles on LiNi_(0.5)Mn_(0.3)Co_(0.2)O_(2)(NMC532)has been designed through a room-temperature-and-pressure chemical vapor deposition technique.The selective growth of PANTI on NMC532 is based on theoretical computation results that multivalent Ni,Mn,and Co are capable of specifically conjugating and activating aniline molecules and,hence,initiating in-situ oxidation polymerization.With only trace amount of aniline monomer,the resulting PANI nanoparticles-inlaid NMC532 microparticles can endure four-month ageing in ambient atmosphere and exhibit improved electrochemical performance at both room temperature and 55℃ compared with pristine NMC532.The improved electrochemical performance of NMC532/PANI is attributed to the enhanced structural stability of NMC532 and inhibited side reactions related to Li_(2)CO_(3) formation,PVDF degradation,electrolyte decomposition,and transition-metal dissolution,owing to PANI modification.展开更多
Silver‐modified semiconductor photocatalysts typically exhibit enhanced photocatalytic activitytoward the degradation of organic substances.In comparison,their hydrogen‐evolution rates arerelatively low owing to poo...Silver‐modified semiconductor photocatalysts typically exhibit enhanced photocatalytic activitytoward the degradation of organic substances.In comparison,their hydrogen‐evolution rates arerelatively low owing to poor interfacial catalytic reactions to producing hydrogen.In the presentstudy,thiocyanate anions(SCN–)as interfacial catalytic active sites were selectively adsorbed ontothe Ag surface of g‐C3N4/Ag photocatalyst to promote interfacial H2‐evolution reactions.The thiocyanate‐modified g‐C3N4/Ag(g‐C3N4/Ag‐SCN)photocatalysts were synthesized via photodepositionof metallic Ag on g‐C3N4and subsequent selective adsorption of SCN– ions on the Ag surface by animpregnation method.The resulting g‐C3N4/Ag‐SCN photocatalysts exhibited considerably higherphotocatalytic H2‐evolution activity than the g‐C3N4,g‐C3N4/Ag,and g‐C3N4/SCN photocatalysts.Furthermore,the g‐C3N4/Ag‐SCN photocatalyst displayed the highest H2‐evolution rate(3.9μmolh?1)when the concentration of the SCN– ions was adjusted to0.3mmol L?1.The H2‐evolution rateobtained was higher than those of g‐C3N4(0.15μmol h?1)and g‐C3N4/Ag(0.71μmol h?1).Consideringthe enhanced performance of g‐C3N4/Ag upon minimal addition of SCN– ions,a synergistic effectof metallic Ag and SCN– ions is proposed―the Ag nanoparticles act as an effective electron‐transfermediator for the steady capture and rapid transportation of photogenerated electrons,while theadsorbed SCN– ions serve as an interfacial active site to effectively absorb protons from solution andpromote rapid interfacial H2‐evolution reactions.Considering the present facile synthesis and itshigh efficacy,the present work may provide new insights into preparing high‐performance photocatalytic materials展开更多
In the field of volatile organic compounds(VOCs)pollution control,adsorption is one of the major control methods,and effective adsorbents are desired in this technology.In this work,the density functional theory(DFT)c...In the field of volatile organic compounds(VOCs)pollution control,adsorption is one of the major control methods,and effective adsorbents are desired in this technology.In this work,the density functional theory(DFT)calculations are employed to investigate the adsorption of typical VOCs molecules on the two-dimensional material borophenes.The results demonstrate that both structure ofχBorophene;2D material;Volatile organic compounds(VOCs);Selective adsorption;Electronic structure andβ12 borophene can chemically adsorb ethylene and formaldehyde with forming chemical bonds and releasing large energy.However,other VOCs,including ethane,methanol,formic acid,methyl chloride,benzene and toluene,are physically adsorbed with weak interaction.The analysis of density of states(DOS)reveals that the chemical adsorption changes the conductivity of borophenes,while the physical adsorption has no distinct effect on the conductivity.Therefore,bothχ^(3)andβ_(12) borophene are appropriate adsorbents for selective adsorption of ethylene and formaldehyde,and they also have potential in gas sensor applications due to the obvious conductivity change during the adsorption.展开更多
Porous carbon membranes were favorably fabricated through the pyrolysis of polyacrylonitrile（PAN） precursors, which were prepared with a template-free technique-thermally induced phase separation. These carbon membr...Porous carbon membranes were favorably fabricated through the pyrolysis of polyacrylonitrile（PAN） precursors, which were prepared with a template-free technique-thermally induced phase separation. These carbon membranes possess hierarchical pores, including cellular macropores across the whole membranes and much small pores in the matrix as well as on the pore walls. Nitrogen adsorption indicates micropores（1.47 and 1.84 nm） and mesopores（2.21 nm） exist inside the carbon membranes, resulting in their specific surface area as large as 1062 m2/g. The carbon membranes were used to adsorb organic dyes（methyl orange, Congo red, and rhodamine B） from aqueous solutions based on their advantages of hierarchical pore structures and large specific surface area. It is particularly noteworthy that the membranes present a selective adsorption towards methyl orange, whose molecular size（1.2 nm） is smaller than those of Congo red（2.3 nm） and rhodamine B（1.8 nm）. This attractive result can be attributed to the steric structure matching between the molecular size and the pore size, rather than electrostatic attraction. Furthermore, the used carbon membranes can be easily regenerated by hydrochloric acid, and their recovery adsorption ratio maintains above 90% even in the third cycle. This work may provide a new route for carbon-based adsorbents with hierarchical pores via a template-free approach, which could be promisingly applied to selectively remove dye contaminants in aqueous effluents.展开更多
The adsorption behavior of CO_2, CH_4 and their mixtures in bituminous coal was investigated in this study. First, a bituminous coal model was built through molecular dynamic(MD) simulations, and it was confirmed to b...The adsorption behavior of CO_2, CH_4 and their mixtures in bituminous coal was investigated in this study. First, a bituminous coal model was built through molecular dynamic(MD) simulations, and it was confirmed to be reasonable by comparing the simulated results with the experimental data. Grand Canonical Monte Carlo(GCMC)simulations were then carried out to investigate the single and binary component adsorption of CO_2 and CH_4with the built bituminous coal model. For the single component adsorption, the isosteric heat of CO_2 adsorption is greater than that of CH_4 adsorption. CO_2 also exhibits stronger electrostatic interactions with the heteroatom groups in the bituminous coal model compared with CH_4, which can account for the larger adsorption capacity of CO_2 in the bituminous coal model. In the case of binary adsorption of CO_2 and CH_4mixtures, CO_2 exhibits the preferential adsorption compared with CH_4 under the studied conditions. The adsorption selectivity of CO_2 exhibited obvious change with increasing pressure. At lower pressure, the adsorption selectivity of CO_2 shows a rapid decrease with increasing the temperature, whereas it becomes insensitive to temperature at higher pressure. Additionally, the adsorption selectivity of CO_2 decreases gradually with the increase of the bulk CO_2 mole fraction and the depth of CO_2 injection site.展开更多
Surfactant enhanced elution is an effective method for removing hydrophobic organic pollutants from soils.The key to the development of leaching technology is selective removal of targeted pollutants in soil washing e...Surfactant enhanced elution is an effective method for removing hydrophobic organic pollutants from soils.The key to the development of leaching technology is selective removal of targeted pollutants in soil washing effluent and recycling of surfactant solutions.In this study,a molecular imprinting technique was applied to selectively sorb polybrominated diphenyl ethers(PBDEs)in soil washing effluent.The novel molecular imprinted polymers(MIPs)using different template molecules were synthesized by precipitation polymerization.Adsorption behaviors andmechanisms ofMIPs were studied through experiments and theoretical calculations.The results show that 4-bromo-4'-hydroxybiphenyl and toluene can be effective imprinting molecule for MIPs synthesis.The maximal adsorption capacity of selected dummy molecular imprinted polymer(D1-MIP)was 1032.36μmol/g,and that of part molecular imprinted polymer(P-MIP)was 981.13μmol/g.Their imprinting factors in 5 PBDEs adsorption ranged from 2.13 to 5.88,the recovery percentage of Triton X-100 can reach 99.09%,confirming the feasibility of reusing surfactant.Various PBDEs could be removed by MIPs,and Quantitative Structure Property Relationship analysis revealed that PBDEs’molecular volume,planarity,polarity,and hydrophobicity have major influences on their adsorption performance.DFT calculation revealed that Van derWaals force and hydrogen bonding played important roles during selective adsorption.These results can provide effective theoretical guidance for surfactant enhanced soil elution in practical engineering applications.展开更多
An unexpected in-situ hydrolysis reaction occurred during the solvothermal reaction of N,N’-bis(4-carboxy-2-methylphenyl)pyromellitic di-imide)and Ba(NO3)2,and a novel porous Ba-MOF,[H_(2)N(CH_(3))_(2)]_(0.5)[Ba_(1.5...An unexpected in-situ hydrolysis reaction occurred during the solvothermal reaction of N,N’-bis(4-carboxy-2-methylphenyl)pyromellitic di-imide)and Ba(NO3)2,and a novel porous Ba-MOF,[H_(2)N(CH_(3))_(2)]_(0.5)[Ba_(1.5)(L)(DMA)]·1.5 DMA·1.5 H_(2)O(UPC-70,H_(3)L=2-(4-ca rboxy-2-methylphenyl)-1,3-dioxoisoindoline-5,6-dicarboxylic acid,DMA=N,N-dimethylacetamide),was obtained on the basis of the partial hydrolysate.The as-synthesized 3 D network with 1 D open channels of different sizes(24 A and 10 A)contains abundant open metal sites after removal of solvents,which is conducive to the preferential adsorption of CO_(2).The subsequent gas sorption measurement reveals the high separation selectivity of UPC-70 for CO_(2)/CH_(4)(15)and CO_(2)/N_(2)(32)at ambient conditions,and GCMC theoretical simulation provides good verification of the experimental results,indicating that UPC-70 is a potential candidate for CO_(2)capture from flue gas and natural gas.展开更多
Rare earth elements(REE)are strategic resources and the recycling of REE in alternative resources is urgent and gets increasingly attention.However,the separation of REE in these alternative resources is still a chall...Rare earth elements(REE)are strategic resources and the recycling of REE in alternative resources is urgent and gets increasingly attention.However,the separation of REE in these alternative resources is still a challenge due to the low concentration of REE and multi coexisted ions in acidic system.In this study,the species distribution of REE within the pH 0-8.0 was calculated.The SBA-15 originated from coal fly ash was modified by two steps with(3-aminopropyl)triethoxysilane(APTES)and diethylenetriaminepentaacetic dianhydride(DTPADA)to obtain DTPADA-SBA-15 adsorbent,which was applied to the selective adsorption of REE.The results showed that DTPADA-SBA-15 possessed excellent adsorption performance on the selective adsorption of REE,including Eu,Gd,Tb,Nd and Sm,in acidic solution(pH 2)with multi competing ions.The FT-IR and Zeta potential characterization verified that the chemical adsorption through the coordination of O in DTPADA-SBA-15 with REE was dominant at lower pH value.The study of adsorption kinetics indicated that the adsorption of rare earth metal ions followed pseudosecond-order kinetic,of which the adsorption process followed the Langmuir isotherm model.展开更多
基金supported by the National Natural Science Foundation of China(22175136)the State Key Laboratory of Electrical Insulation and Power Equipment(EIPE23127)the Fundamental Research Funds for the Central Universities(xtr052024009).
文摘Metal hydrides with high hydrogen density provide promising hydrogen storage paths for hydrogen transportation.However,the requirement of highly pure H_(2)for re-hydrogenation limits its wide application.Here,amorphous Al_(2)O_(3)shells(10 nm)were deposited on the surface of highly active hydrogen storage material particles(MgH_(2)-ZrTi)by atomic layer deposition to obtain MgH_(2)-ZrTi@Al_(2)O_(3),which have been demonstrated to be air stable with selective adsorption of H_(2)under a hydrogen atmosphere with different impurities(CH_(4),O_(2),N_(2),and CO_(2)).About 4.79 wt% H_(2)was adsorbed by MgH_(2)-ZrTi@10nmAl_(2)O_(3)at 75℃under 10%CH_(4)+90%H_(2)atmosphere within 3 h with no kinetic or density decay after 5 cycles(~100%capacity retention).Furthermore,about 4 wt%of H_(2)was absorbed by MgH_(2)-ZrTi@10nmAl_(2)O_(3)under 0.1%O_(2)+0.4%N_(2)+99.5%H_(2)and 0.1%CO_(2)+0.4%N_(2)+99.5%H_(2)atmospheres at 100℃within 0.5 h,respectively,demonstrating the selective hydrogen absorption of MgH_(2)-ZrTi@10nmAl_(2)O_(3)in both oxygen-containing and carbon dioxide-containing atmospheres hydrogen atmosphere.The absorption and desorption curves of MgH_(2)-ZrTi@10nmAl_(2)O_(3)with and without absorption in pure hydrogen and then in 21%O_(2)+79%N_(2)for 1 h were found to overlap,further confirming the successful shielding effect of Al_(2)O_(3)shells against O_(2)and N_(2).The MgH_(2)-ZrTi@10nmAl_(2)O_(3)has been demonstrated to be air stable and have excellent selective hydrogen absorption performance under the atmosphere with CH_(4),O_(2),N_(2),and CO_(2).
基金supported by The National Natural Science Foundation of China(22471289 and 22478430)Shandong Natural Science Foundation(ZR2022ME105 and ZR2023ME004)+4 种基金Qingdao Natural Science Foundation(23-2-1-232-zyyd-jch)Geological body description and key technologies of reservoir engineering of CCUS oil displacement(2021ZZ01-03)Science and Technology Major Project on New Oil and Gas Exploration and Development:Research on Comprehensive Control Technology for CO_(2)-Enhanced Miscible and Immiscible Displacement(2024ZD1406601)State Key Laboratory of Enhanced Oil Recovery of Open Fund Funded Project(2024-KFKT-19)the Fundamental Research Funds for the Central Universities(24CX06042A and 24CX06070A)。
文摘The rational design of high-performance CO_(2)adsorbents remains a critical challenge in addressing global carbon emissions,with metal-organic frameworks(MOFs)emerging as promising candidates due to their tunable pore environments.However,the lack of systematic guidelines for functional group selection has hindered their practical implementation in carbon capture applications.Here,this gap was addressed by developing a comprehensive design framework through high-throughput computational screening.Through construction of a topology-directed database of 4797,integrating 10 metal centers with 144 functionalized ligands(18 ligands modified by–NH_(2),–NO_(2),–CH_(3),–CF_(3),–SH_(2),–SO_(2),–OH,and–OLi)across 36 topologies,the fundamental structure–property relationships governing CO_(2)capture performance was established.Multi-metric evaluation reveals that–NO_(2),–SO_(2),and–OLi dramatically enhance CO_(2)selectivity over CH_4/N_(2)via selectivity(S_(ads)),working capacity(ΔN),adsorbent performance score(APS),sorbent selection parameter(S_(sp)),and renewability R.Specially,ΔN rises from 2.34(pristine)to 5.91–7.94 mmol g^(-1)and S_(ads)surges from 24.94/40.36 to 121.11/176.87(–NO_(2)),149.94/215.54(–SO_(2)),and 58.64/267.44(–OLi).Besides,the critical trade-off between adsorption strength and renewability demonstrates that enhanced performance comes at the cost of reduced renewability,where stronger CO_(2)affinity(isosteric heat of-29.15,-29.96,and-30.09 for–NO_(2),–SO_(2),and–OLi)compromises renewability(R reduced by -50%).To resolve this trade-off,a novel energy efficiency(η)metric was introduced,which holistically evaluates both adsorption performance(S_(ads),ΔN,APS,S_(sp),and R)and energy inputs(desorption heat,pressure-swing energy,net loss).This leads to the identification of–SO_(2)as the optimal functional group that balances exceptional CO_(2)capture(η=6.17/12.78 for CO_(2)over CH_4/N_(2)),surpassing the second higher of 4.74/8.80 in–CF_(3)and 0.99/2.18 in non-functionalized counterparts.Adopting high-throughput computational screening methods,this work provides both fundamental insights into host–vip interactions in functionalized MOFs and a practical framework for designing next-generation adsorbents,bridging the gap between materials discovery and process engineering considerations in carbon capture technologies.
文摘Metal ion-imprintedly crosslinked chitosan resin 1 and resin 2 were prepared by theuse of Cu2+ and Ni2+ as template ions and glutaraldehyde as crosslinking agent, respectively.Through investigation on the adsorption capacities and binding constants for Cu2+, Ni2+andCo2+ ions on chitosan resins, resin 1 and resin 2 exhibit the adsorption selectivity for themixture solution of 1:1 Cu2+ and Ni2+ ions. The adsorption selectivity of metal ion-imprintedresins for their template ions is much higher than that of uncrosslinked chitosan resin.
文摘We report a robust pillar-layered metal-organic framework,Zn‑tfbdc‑dabco(tfbdc:tetrafluoroterephthal-ate,dabco:1,4-diazabicyclo[2.2.2]octane),featuring the fluorinated pore environment,for the preferential binding of propane over propylene and thus highly inverse selective separation of propane/propylene mixture.The inverse propane-selective performance of Zn‑tfbdc‑dabco for the propane/propylene separation was validated by single-component gas adsorption isotherms,isosteric enthalpy of adsorption calculations,ideal adsorbed solution theory calculations,along with the breakthrough experiment.The customized fluorinated networks served as a propane-trap to form more interactions with the exposed hydrogen atoms of propane,as unveiled by the simulation studies at the molecular level.With the advantage of inverse propane-selective adsorption behavior,high adsorption capacity,good cycling stability,and low isosteric enthalpy of adsorption,Zn‑tfbdc‑dabco can be a promising candidate adsorbent for the challenging propane/propylene separation to realize one-step purification of the target propylene substance.
基金The Natural Science Foundation of Jiangsu Province(No.BK2009262)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry
文摘A novel porous coordination polymer,iron naphthalenedicarboxylate Fe（OH）（1,4-NDC）·2H2O is hydrothermally synthesized by the reaction of FeSO4·7H2O and 1,4-naphthalenedicarboxylic acid（1,4-H2NDC） at 150℃.The compound crystallizes in a tetragonal space group P42/nmc：a=2.1447（4） nm,c=0.68849（14） nm,V=3.1669（11） nm3,Z=8,R=0.0845,wR=0.1829.The crystal structure exhibits a three-dimensional framework which is composed of infinite chains of corner-sharing octahedral Fe（OH）2O4 with 1,4-NDC ligands forming two types of channels with square-shaped cross-sections.The large channels present a cross-section of 0.76 nm×0.76 nm,while the small channels are about 0.30 nm×0.30 nm.No structural transformation occurs after removing the vip water molecules,while a robust structure generates with permanent porosity.The adsorption measurements show that the anhydrous sample of the compound can adsorb CO2 into its pores.The adsorption isotherms for methanol,acetone,tetrahydrofuran and benzene are also measured.
基金Funded by the National Natural Science Foundation of China (No.20803055)the Fundamental Research Funds for the Central Universities(Nos.2011-1a-39 and 2011-1a-16)
文摘The AgBr powder was prepared by a hydrothermal method via a reaction of AgNO3 with hexadecyltrimethy ammonium bromide（CTAB）,namely,CTAB-assisted synthesis method.The selective-adsorption ability of the AgBr samples for the MO was evaluated in a MO and Rhodamine B mixed solution via ultraviolet-visible spectra.Compared with the AgBr sample prepared from NaBr solution,it was found that the AgBr powder synthesized by CTAB-assisted method exhibited high selective-adsorption performance for the MO in the MO-RhB mixed system.After aged for 60 min,the MO could be efficiently removed by CTAB-assisted AgBr powder.Considering the potential wide applications of the selective adsorption,the CTAB-assisted AgBr provides a new and efficient method for the removal of various dyes and is possible to be widely used in industries.
基金supported by the National Natural Science Foundation of China(Nos.22365026 and 21966028)the Science and Technology Project of Gansu(No.21YF5GA062)+3 种基金the Fundamental Research Funds for the Central Universities(Nos.31920220043,31920240094,and 31920230142)the Education Department of Gansu Province:Excellent Graduate student“Innovation Star”project(No.2023CXZX-202)Gansu Province Science Foundation for Youths(No.24JRRA160)the Funds for Special Projects of the Central Government in Guidance of Local Science and Technology Development(No.24ZY1QA026).
文摘The effective and environmentally friendly management of oily wastewater,alongside the beneficial conversion of waste biomass,holds paramount importance for environmental conservation,public health,and sustainable societal progress.In this research,an innovative biomass core-shell bioreactor(CGC@SiO_(2) aerogel) with selective adsorption and degradation properties was developed.The reactor's core is composed of coffee cellulose aerogel,offering a porous framework conducive to microbial colonization while safeguarding microorganisms from adverse external factors.The shell integrates hydrophobic silica enriched with polydimethylsiloxane,which alters the material's hydrophilic properties,enabling it to remain afloat on water for up to 100 days.This superhydrophobic layer maintained a contact angle of 150° even after ten consecutive rubbings.Experimental results indicate that the material performs exceptionally well in oil-water separation,as demonstrated by its success in 9 consecutive oil-water separations.It achieved 99 % selective adsorption,91 % removal,and 46.2 % degradation of a 3 wt.% diesel solution under conditions of 37℃,120 r/min,and pH=7.Additionally,tests assessing environmental tolerance revealed the material's robust adaptability and stability across varying pH levels and temperatures.Compared to traditional hydrophobic and lipophilic materials or free-floating microorganisms,CGC@SiO2 aerogel not only efficiently captures oil pollutants but also degrades them into non-hazardous substances.Combining biodegradation with selective adsorption has shown to be an effective approach for treating oily wastewater,offering significant practical application potential.The low-carbon production of CGC@SiO2aerogel aligns with circular economy principles,underscoring its role in sustainable development.
基金supported by the National Natural Science Foundation of China grant nos.52470149(P.H.Shao)and 52125002(X.B.Luo)the National Key Research and Development Program of China grant no.2023YFC3905903(P.H.Shao)Nanchang Hangkong University Doctoral Start-up Fund grant no.EA202502100(Y.Y.Zhou).
文摘Selective extraction of precious metals from urban mines plays a crucial role in mitigating the risk of depletion of precious metal resources and reducing waste pollution.However,a major obstacle in precious metal extraction lies in the difficulty of distinguishing the subtle differences in the physicochemical characteristics between them,especially gold and palladium.Herein,a proton-driven separation system was presented for cascade recovery of gold and palladium from waste-printed circuit boards(W-PCBs)leachate using poly(amidoxime)(PAO)hydrogel.This exhibits an ultra-high capacity,extra-fast rate,and excellent selectivity for the extraction of Au(Ⅲ)and Pd(Ⅱ).Notably,the separation of Au(Ⅲ)and Pd(Ⅱ)can be achieved with high selectivity at pH=0,resulting in a remarkable separation factor of k_(Au(Ⅲ)/Pd(Ⅱ))=36.5.This was demonstrated to originate from the differential mechanism of PAO hydrogel for the capture of Au(Ⅲ)and Pd(Ⅱ)under proton-mediated conditions.Drawing inspiration from the mechanism,the proton-driven cascade recovery system demonstrates remarkable efficiency in sequentially recovering 99.92%of gold and 99.05%of palladium from W-PCBs acid leachate.This research opens up a strategy to precisely separate and recover precious metals from e-waste of urban mines.
文摘A novel Ni（Ⅱ） ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid（AMPS） as a functional monomer for the selective separation of Ni（Ⅱ） from aqueous solution. The sorbent showed good chemical and thermal stability. Kinetics studies indicated that the equilibrium adsorption was achieved within 10 min and the adsorption kinetics fitted well with the pseudo-second-order kinetic model. The maximum adsorption capacity of the ion-imprinted polymer towards Ni（Ⅱ） at the optimal p H of 7.0 was 66.22 mg·g^（-1）. The relative selectivity coefficients of the sorbent were 9.23, 15.71, 14.72 and 20.15 for Ni（Ⅱ）/Co（Ⅱ）, Ni（Ⅱ）/Cu（Ⅱ）, Ni（Ⅱ）/Zn（Ⅱ） and Ni（Ⅱ）/Pb（Ⅱ）, respectively. The adsorption isotherm fitted well with Langmuir isotherm model. The thermodynamic results indicated that the adsorption of Ni（Ⅱ） was a spontaneous and endothermic process. The sorbent showed good reusability evidenced by six cycles of adsorption/desorption experiments. The precision of this method is satisfactory. Thus, the prepared sorbent can be considered as a promising sorbent for selective separation of Ni（Ⅱ） in real water samples.
基金Project (2014CB643401) supported by the National Basic Research Program of ChinaProjects (51134007,51474256) supported by the National Natural Science Foundation of ChinaProject (2016TP1007) supported by the Hunan Provincial Science and Technology Plan Project in China
文摘A novel silica-supported tert-butyl 2-picolyamino-N-acetate chelating resin (Si-AMPY-1) was successfully synthesized and characterized by elemental analysis, FT-IR, SEM and 13 C CP/MAS NMR. The adsorption behaviors of the Si-AMPY-1 resin for Cu(Ⅱ) and Ni(Ⅱ) were studied with batch and column methods. The batch experiments indicated that the Si-AMPY-1 resin adsorbed Ni(Ⅱ) mainly via physisorption, while adsorbed Cu(II) via chemisorption. The column dynamic breakthrough curves revealed thatthe Si-AMPY-1 resin can efficiently separate Cu(Ⅱ) from the simulated nickel electrolyte before the breakthrough point. Moreover, the concentration of Cu(Ⅱ) in the column effluent was decreased to be less than 3 mg/L within the first 43 BV (bed volumes), and the mass ratio of Cu/Ni was 21:1 in the saturated resin, which completely satisfied the industrial requirements of the nickel electrorefining process. Therefore, it was concluded that the Si-AMPY-1 resin can be a promising candidate for the deep removal of Cu(Ⅱ) from the nickel electrolyte.
基金This work was supported by the National Science Fund for Excellent Young Scholars(21722606)the National Natural Science Foundation of China(21676138,21878149,21808110,and 21576137)+1 种基金the China Postdoctoral Science Foundation(2018M632295)the Six Talent Plan(2016XCL031).
文摘Achieving efficient adsorption and desorption processes by controllably tuning the properties of adsorbents at different technical stages is extremely attractive.However,it is difficult for traditional adsorbents to reach the target because of their fixed active sites.Herein,we report on the fabrication of a smart adsorbent,which was achieved by introducing photoresponsive azobenzene derivatives with cis/trans isomers to Ce-doped mesoporous silica.These photoresponsive groups serve as “molecular switches”by sheltering and exposing active sites,leading to efficient adsorption and desorption.Ce is also doped to provide additional active sites in order to enhance the adsorption performance.The results show that the cis isomers effectively shelter the active sites,leading to the selective adsorption of methylene blue(MB)over brilliant blue(BB),while the trans isomers completely expose the active sites,resulting in the convenient release of the adsorbates.Both selective adsorption and efficient desorption can be realized controllably by these smart adsorbents through photostimulation.Moreover,the performance of the obtained materials is well maintained after five cycles.
基金Project supported by National Basic Research Program of China(973 Program)(2012CBA01205)
文摘The flotation performances of styrene phosphonic acid（SPA） to synthetic（Ce,La）2O3（REO）, calcium fluorite（CaF2） and fluorapatite（Ca5F（PO4）3） were investigated by flotation tests, flotation of synthetic mixed mineral, the surface adsorption capacity and the polarizing microscopy to solve the flotation separation problem of rare earth oxides from roasted concentrate. The flotation test results indicated that compared with CaF2 and Ca5F（PO4）3, SPA exhibited superior collecting performance to direct flotation recovery of REO and floated out above 90% REO at pH 3–6. However, the collecting ability of SPA to CaF2 and Ca5F（PO4）3 was extremely weak and the highest recovery was only 20% at pH 2–11. The flotation of synthetic mixed mineral showed that SPA was a good collector reagent for flotation of synthetic REO at pH 5, so REO, CaF2 and Ca5F（PO4）3 could be separated from roasted concentrate by using SPA as a collector. The surface adsorption capacity tests and polarizing microscopy results confirmed that SPA was adsorbed on REO surface, while CaF2 and Ca5F（PO4）3 were not. The adsorption mechanism of SPA to synthetic REO was studied by solution chemistry analysis of collector, the ζ-potential tests, infrared spectroscopy and X-ray photoelectron spectroscopy（XPS） analyses. The results indicated that SPA was physically adsorbed onto REO surface, which exhibited excellent flotation selectivity to REO against CaF2 and Ca5F（PO4）3.
基金financially supported by the Natural Science Foundation of Shandong Province(ZR2019MEM015 and ZR2017QB003)Young Taishan Scholar Program of Shandong Province(No.tsqn201909139)the Introduction and Cultivation Plan of Young Innovative Talents in Colleges and Universities of Shandong Province。
文摘Surface modification offers an alternative strategy to improve both ageing resistance and electrochemical performance of cathode materials for lithium-ion batteries.From the viewpoint of real application,surface modification of the cathode materials should be designed with scientificity,effectiveness,low cost,less Li+leaching,and remained tap density.In this contribution,a selective adsorption-involved in-situ growth of polyaniline(PANI)nanoparticles on LiNi_(0.5)Mn_(0.3)Co_(0.2)O_(2)(NMC532)has been designed through a room-temperature-and-pressure chemical vapor deposition technique.The selective growth of PANTI on NMC532 is based on theoretical computation results that multivalent Ni,Mn,and Co are capable of specifically conjugating and activating aniline molecules and,hence,initiating in-situ oxidation polymerization.With only trace amount of aniline monomer,the resulting PANI nanoparticles-inlaid NMC532 microparticles can endure four-month ageing in ambient atmosphere and exhibit improved electrochemical performance at both room temperature and 55℃ compared with pristine NMC532.The improved electrochemical performance of NMC532/PANI is attributed to the enhanced structural stability of NMC532 and inhibited side reactions related to Li_(2)CO_(3) formation,PVDF degradation,electrolyte decomposition,and transition-metal dissolution,owing to PANI modification.
基金supported by the National Natural Science Foundation of China(51472192,21477094,21771142)the Fundamental Research Funds for the Central Universities(WUT 2017IB002)~~
文摘Silver‐modified semiconductor photocatalysts typically exhibit enhanced photocatalytic activitytoward the degradation of organic substances.In comparison,their hydrogen‐evolution rates arerelatively low owing to poor interfacial catalytic reactions to producing hydrogen.In the presentstudy,thiocyanate anions(SCN–)as interfacial catalytic active sites were selectively adsorbed ontothe Ag surface of g‐C3N4/Ag photocatalyst to promote interfacial H2‐evolution reactions.The thiocyanate‐modified g‐C3N4/Ag(g‐C3N4/Ag‐SCN)photocatalysts were synthesized via photodepositionof metallic Ag on g‐C3N4and subsequent selective adsorption of SCN– ions on the Ag surface by animpregnation method.The resulting g‐C3N4/Ag‐SCN photocatalysts exhibited considerably higherphotocatalytic H2‐evolution activity than the g‐C3N4,g‐C3N4/Ag,and g‐C3N4/SCN photocatalysts.Furthermore,the g‐C3N4/Ag‐SCN photocatalyst displayed the highest H2‐evolution rate(3.9μmolh?1)when the concentration of the SCN– ions was adjusted to0.3mmol L?1.The H2‐evolution rateobtained was higher than those of g‐C3N4(0.15μmol h?1)and g‐C3N4/Ag(0.71μmol h?1).Consideringthe enhanced performance of g‐C3N4/Ag upon minimal addition of SCN– ions,a synergistic effectof metallic Ag and SCN– ions is proposed―the Ag nanoparticles act as an effective electron‐transfermediator for the steady capture and rapid transportation of photogenerated electrons,while theadsorbed SCN– ions serve as an interfacial active site to effectively absorb protons from solution andpromote rapid interfacial H2‐evolution reactions.Considering the present facile synthesis and itshigh efficacy,the present work may provide new insights into preparing high‐performance photocatalytic materials
基金supported by the National Natural Science Foundation of China(Nos.21777033 and 41807191)Science and Technology Planning Project of Guangdong Province(No.2017B020216003)+2 种基金Natural Science Foundation of Guangdong Province,China(No.2018A030310524)Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01Z032)the Innovation Team Project of Guangdong Provincial Department of Education(No.2017KCXTD012)。
文摘In the field of volatile organic compounds(VOCs)pollution control,adsorption is one of the major control methods,and effective adsorbents are desired in this technology.In this work,the density functional theory(DFT)calculations are employed to investigate the adsorption of typical VOCs molecules on the two-dimensional material borophenes.The results demonstrate that both structure ofχBorophene;2D material;Volatile organic compounds(VOCs);Selective adsorption;Electronic structure andβ12 borophene can chemically adsorb ethylene and formaldehyde with forming chemical bonds and releasing large energy.However,other VOCs,including ethane,methanol,formic acid,methyl chloride,benzene and toluene,are physically adsorbed with weak interaction.The analysis of density of states(DOS)reveals that the chemical adsorption changes the conductivity of borophenes,while the physical adsorption has no distinct effect on the conductivity.Therefore,bothχ^(3)andβ_(12) borophene are appropriate adsorbents for selective adsorption of ethylene and formaldehyde,and they also have potential in gas sensor applications due to the obvious conductivity change during the adsorption.
基金financially supported by the National Natural Science Foundation of China(No.21174124)K.C.Wong Magna Fund in Ningbo University
文摘Porous carbon membranes were favorably fabricated through the pyrolysis of polyacrylonitrile（PAN） precursors, which were prepared with a template-free technique-thermally induced phase separation. These carbon membranes possess hierarchical pores, including cellular macropores across the whole membranes and much small pores in the matrix as well as on the pore walls. Nitrogen adsorption indicates micropores（1.47 and 1.84 nm） and mesopores（2.21 nm） exist inside the carbon membranes, resulting in their specific surface area as large as 1062 m2/g. The carbon membranes were used to adsorb organic dyes（methyl orange, Congo red, and rhodamine B） from aqueous solutions based on their advantages of hierarchical pore structures and large specific surface area. It is particularly noteworthy that the membranes present a selective adsorption towards methyl orange, whose molecular size（1.2 nm） is smaller than those of Congo red（2.3 nm） and rhodamine B（1.8 nm）. This attractive result can be attributed to the steric structure matching between the molecular size and the pore size, rather than electrostatic attraction. Furthermore, the used carbon membranes can be easily regenerated by hydrochloric acid, and their recovery adsorption ratio maintains above 90% even in the third cycle. This work may provide a new route for carbon-based adsorbents with hierarchical pores via a template-free approach, which could be promisingly applied to selectively remove dye contaminants in aqueous effluents.
基金Supported by the CNPC Huabei Oilfield Science and Technology Development Project(HBYT-CYY-2014-JS-378,HBYT-CYY-2015-JS-47)
文摘The adsorption behavior of CO_2, CH_4 and their mixtures in bituminous coal was investigated in this study. First, a bituminous coal model was built through molecular dynamic(MD) simulations, and it was confirmed to be reasonable by comparing the simulated results with the experimental data. Grand Canonical Monte Carlo(GCMC)simulations were then carried out to investigate the single and binary component adsorption of CO_2 and CH_4with the built bituminous coal model. For the single component adsorption, the isosteric heat of CO_2 adsorption is greater than that of CH_4 adsorption. CO_2 also exhibits stronger electrostatic interactions with the heteroatom groups in the bituminous coal model compared with CH_4, which can account for the larger adsorption capacity of CO_2 in the bituminous coal model. In the case of binary adsorption of CO_2 and CH_4mixtures, CO_2 exhibits the preferential adsorption compared with CH_4 under the studied conditions. The adsorption selectivity of CO_2 exhibited obvious change with increasing pressure. At lower pressure, the adsorption selectivity of CO_2 shows a rapid decrease with increasing the temperature, whereas it becomes insensitive to temperature at higher pressure. Additionally, the adsorption selectivity of CO_2 decreases gradually with the increase of the bulk CO_2 mole fraction and the depth of CO_2 injection site.
基金This work was supported by the National Natural Science Foundation of China(Nos.42077114 and 41771346)the Local Innovation and Entrepreneurship Team Project of Guangdong Special Support Program(No.2019BT02L218)Zhaoqing University Innovation Research Team Funding Project.
文摘Surfactant enhanced elution is an effective method for removing hydrophobic organic pollutants from soils.The key to the development of leaching technology is selective removal of targeted pollutants in soil washing effluent and recycling of surfactant solutions.In this study,a molecular imprinting technique was applied to selectively sorb polybrominated diphenyl ethers(PBDEs)in soil washing effluent.The novel molecular imprinted polymers(MIPs)using different template molecules were synthesized by precipitation polymerization.Adsorption behaviors andmechanisms ofMIPs were studied through experiments and theoretical calculations.The results show that 4-bromo-4'-hydroxybiphenyl and toluene can be effective imprinting molecule for MIPs synthesis.The maximal adsorption capacity of selected dummy molecular imprinted polymer(D1-MIP)was 1032.36μmol/g,and that of part molecular imprinted polymer(P-MIP)was 981.13μmol/g.Their imprinting factors in 5 PBDEs adsorption ranged from 2.13 to 5.88,the recovery percentage of Triton X-100 can reach 99.09%,confirming the feasibility of reusing surfactant.Various PBDEs could be removed by MIPs,and Quantitative Structure Property Relationship analysis revealed that PBDEs’molecular volume,planarity,polarity,and hydrophobicity have major influences on their adsorption performance.DFT calculation revealed that Van derWaals force and hydrogen bonding played important roles during selective adsorption.These results can provide effective theoretical guidance for surfactant enhanced soil elution in practical engineering applications.
基金supported by the National Natural Science Foundation of China(NSFC,No.21771191)the Fundamental Research Funds for the Central Universities(No.19CX05001A)。
文摘An unexpected in-situ hydrolysis reaction occurred during the solvothermal reaction of N,N’-bis(4-carboxy-2-methylphenyl)pyromellitic di-imide)and Ba(NO3)2,and a novel porous Ba-MOF,[H_(2)N(CH_(3))_(2)]_(0.5)[Ba_(1.5)(L)(DMA)]·1.5 DMA·1.5 H_(2)O(UPC-70,H_(3)L=2-(4-ca rboxy-2-methylphenyl)-1,3-dioxoisoindoline-5,6-dicarboxylic acid,DMA=N,N-dimethylacetamide),was obtained on the basis of the partial hydrolysate.The as-synthesized 3 D network with 1 D open channels of different sizes(24 A and 10 A)contains abundant open metal sites after removal of solvents,which is conducive to the preferential adsorption of CO_(2).The subsequent gas sorption measurement reveals the high separation selectivity of UPC-70 for CO_(2)/CH_(4)(15)and CO_(2)/N_(2)(32)at ambient conditions,and GCMC theoretical simulation provides good verification of the experimental results,indicating that UPC-70 is a potential candidate for CO_(2)capture from flue gas and natural gas.
基金the National Natural Science Foundation of China(U1810205)Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi Province(2020L0022)Key Research and Development Program of Shanxi Province(201903D311006).
文摘Rare earth elements(REE)are strategic resources and the recycling of REE in alternative resources is urgent and gets increasingly attention.However,the separation of REE in these alternative resources is still a challenge due to the low concentration of REE and multi coexisted ions in acidic system.In this study,the species distribution of REE within the pH 0-8.0 was calculated.The SBA-15 originated from coal fly ash was modified by two steps with(3-aminopropyl)triethoxysilane(APTES)and diethylenetriaminepentaacetic dianhydride(DTPADA)to obtain DTPADA-SBA-15 adsorbent,which was applied to the selective adsorption of REE.The results showed that DTPADA-SBA-15 possessed excellent adsorption performance on the selective adsorption of REE,including Eu,Gd,Tb,Nd and Sm,in acidic solution(pH 2)with multi competing ions.The FT-IR and Zeta potential characterization verified that the chemical adsorption through the coordination of O in DTPADA-SBA-15 with REE was dominant at lower pH value.The study of adsorption kinetics indicated that the adsorption of rare earth metal ions followed pseudosecond-order kinetic,of which the adsorption process followed the Langmuir isotherm model.
