Despite substantial efforts in developing high-performance catalysts for the oxygen reduction reaction(ORR),the persistent challenge lies in the high onset overpotential of the ORR,and the effect of the elec-trolyte s...Despite substantial efforts in developing high-performance catalysts for the oxygen reduction reaction(ORR),the persistent challenge lies in the high onset overpotential of the ORR,and the effect of the elec-trolyte solution cannot be ignored.Consequently,we have systematically investigated the impact of adsorbate species and concentration,as well as solution pH,on the ORR activity on Pt(111)and Pt(poly)electrodes.The results all tend to establish a linear quantitative relationship between the onset potential for ORR and the adsorption equilibrium potential of the adsorbate.This finding indicates the decisive role of adsorbates in the onset potential for ORR,suggesting that the adsorption potential of adsorbates can serve as an intuitive criterion for ORR activity.Additional support for this conclusion is derived from experimental results obtained from the oxygen evolution reaction on Pt(poly)with different adsorbate species and from the hydrogen evolution reaction on Pt(111)with iodine adsorption.We further propose both an empirical equation for the onset potential for ORR and the concept of a potential-regulated adsor-bate shielding effect to elucidate the influence of adsorbates on ORR activity.This study provides new insights into the high onset overpotential of the ORR and offers potential strategies for predicting and enhancingORRactivity inthefuture.展开更多
Characterization of electric properties of nanomaterials usually involves fabricating field effect transistors （FET） and deriving materials properties from device performances. However, the quality of electrode cont...Characterization of electric properties of nanomaterials usually involves fabricating field effect transistors （FET） and deriving materials properties from device performances. However, the quality of electrode contacts in FET devices heavily influences the device performance, which makes it difficult to obtain the intrinsic electric properties of nanomaterials. Dielectric force microscopy （DFM）, a contactless method developed recently, can detect the low-frequency dielectric responses of nanomaterials without electric contact, which avoids the influence of electric contact and can be used to study the intrinsic conductivity of nanomaterials. Here we study the influences of surface adsorbates on the conductivity of ZnO nanowires （NWs） by using FET and DFM methods. The conductivity of ZnO NW is much larger in N2 atmosphere than that in ambient environment as measured by FET device, which is further proven by DFM measurement that the ZnO NW exhibits larger dielectric response in N2 environment, and the influence of electrode contacts on measurement can be ruled out. Based on these results, it can be concluded that the adsorbates on ZnO NW surface highly influence the conductivity of ZnO NW rather than the electrode contact. This work also verifies the capability of DFM in measuring electric properties of nanomaterials.展开更多
The mass spectrometry of gold clusters stabilized by poly（N‐vinyl‐2‐pyrrolidone） （Au：PVP） re‐vealed the presence of Cl adsorbates derived from synthetic precursors, mainly on the Au34 and Au43 clusters. Chang...The mass spectrometry of gold clusters stabilized by poly（N‐vinyl‐2‐pyrrolidone） （Au：PVP） re‐vealed the presence of Cl adsorbates derived from synthetic precursors, mainly on the Au34 and Au43 clusters. Changes in the amount of Cl adsorbates on the Au clusters did not affect the catalytic prop‐erties for the aerobic oxidation of benzyl alcohol, suggesting that the Cl atoms were only weakly bound to the Au clusters. In contrast, the replacement of Cl with Br on the Au34 and Au43 clusters significantly suppressed activity, without any influence on the electronic structure. This result indi‐cated that the Br atoms were strongly bound to the Au clusters and sterically blocked their active sites. The substantial reduction of the catalytic activity by the Br adsorbates suggested that the Au34 and Au43 clusters made a major contribution to the catalytic activity of the Au：PVP.展开更多
Platinum group alloys have an excellent electronic structure for oxidation of alcohols,but the active sites are more susceptible to deactivation by CO adsorbates(CO_(ads)).The precise integration of single-atom and al...Platinum group alloys have an excellent electronic structure for oxidation of alcohols,but the active sites are more susceptible to deactivation by CO adsorbates(CO_(ads)).The precise integration of single-atom and alloy structures is highly attractive for energy conversion but still a challenge.Here,we report an ionexchange coupled in situ reduction strategy to fabricate hollow PtPdTe alloy nanoreactors loaded with atomically dispersed Cu sites(Cu_(SA)/h-PtPdTe NRs).The planted oxyphilic Cu single sites and resulted compressive strains are conductive to modulating the electronic structure of the active sites,which changes the rate-determining step of the reaction while inhibiting the formation of CO_(ads)and modulating the adsorption of intermediates,resulting in the improved activity and stability.Specifically,the obtained Cu_(SA)/h-PtPdTe NRs exhibit an excellent oxidation performance of multiple alcohols,especially for methanol and ethanol,with 8.0 and 10.3 times of the mass activity higher than Pt/C,and the activity could be recovered by refreshing the electrolyte and could be sustained for 72,000 and 36,000 s,respectively.Meanwhile,Cu_(SA)/h-PtPdTe NRs show superior oxidation performance and durability to ethylene glycol and glycerol.This work pioneers the realization of precise modulation of catalytic sites using single atoms and provides an encouraging pathway for the design of efficient and stable electrocatalysts for the oxidation of multiple alcohols,which could broaden the range of options and sources of fuel cells.展开更多
Developing efficient electrocatalysts for the oxygen evolution reaction(OER)under neutral conditions is important for microbial electrolysis cells(MECs).However,the OER kinetics in neutral electrolytes at present are ...Developing efficient electrocatalysts for the oxygen evolution reaction(OER)under neutral conditions is important for microbial electrolysis cells(MECs).However,the OER kinetics in neutral electrolytes at present are extremely sluggish,resulting in high overpotentials that greatly limit the energy conversion efficiencies of MECs.Previous studies failed to probe the adsorbates on surface metal sites of catalysts at the atomic scale and elucidate their influence on the catalytic activities,which has impeded the rational design of efficient neutral OER catalysts with optimal surface structures.Here,using in situ transmission electron microscopy(TEM),in situ X-ray photoelectron spectroscopy(XPS)and in situ low-energy ion scattering studies,we have identified,for the first time,that the electrochemically activated adsorbates on surface metal sites play a critical role in boosting the neutral OER activities of Ru-Ir binary oxide(RuxIryO2)catalysts.The adsorbate-activated RuxIryO2on a glassy carbon electrode achieved a low overpotential of 324 m V at10 m A cm-2in neutral electrolyte,with a 36-fold improvement in turnover frequency compared with that of Ir O2benchmark.Upon application in an MEC system,the resulting full cell showed a decreased voltage of 1.8 V,200 m V lower than the best value reported to date,facilitating efficient synthesis of poly(3-hydroxybutyrate)from bioelectrochemical CO2reduction.Density functional theory(DFT)studies revealed that the enhanced OER activity of RuxIryO2catalyst arose from local structural distortion of adjacent adsorbate-covered Ru octahedra at the catalyst surface and the consequently decreased adsorption energies of OER intermediates on Ir active center.展开更多
Prediction of production decline and evaluation of the adsorbed/free gas ratio are critical for determining the lifespan and production status of shale gas wells.Traditional production prediction methods have some sho...Prediction of production decline and evaluation of the adsorbed/free gas ratio are critical for determining the lifespan and production status of shale gas wells.Traditional production prediction methods have some shortcomings because of the low permeability and tightness of shale,complex gas flow behavior of multi-scale gas transport regions and multiple gas transport mechanism superpositions,and complex and variable production regimes of shale gas wells.Recent research has demonstrated the existence of a multi-stage isotope fractionation phenomenon during shale gas production,with the fractionation characteristics of each stage associated with the pore structure,gas in place(GIP),adsorption/desorption,and gas production process.This study presents a new approach for estimating shale gas well production and evaluating the adsorbed/free gas ratio throughout production using isotope fractionation techniques.A reservoir-scale carbon isotope fractionation(CIF)model applicable to the production process of shale gas wells was developed for the first time in this research.In contrast to the traditional model,this model improves production prediction accuracy by simultaneously fitting the gas production rate and δ^(13)C_(1) data and provides a new evaluation method of the adsorbed/free gas ratio during shale gas production.The results indicate that the diffusion and adsorption/desorption properties of rock,bottom-hole flowing pressure(BHP)of gas well,and multi-scale gas transport regions of the reservoir all affect isotope fractionation,with the diffusion and adsorption/desorption parameters of rock having the greatest effect on isotope fractionation being D∗/D,PL,VL,α,and others in that order.We effectively tested the universality of the four-stage isotope fractionation feature and revealed a unique isotope fractionation mechanism caused by the superimposed coupling of multi-scale gas transport regions during shale gas well production.Finally,we applied the established CIF model to a shale gas well in the Sichuan Basin,China,and calculated the estimated ultimate recovery(EUR)of the well to be 3.33×10^(8) m^(3);the adsorbed gas ratio during shale gas production was 1.65%,10.03%,and 23.44%in the first,fifth,and tenth years,respectively.The findings are significant for understanding the isotope fractionation mechanism during natural gas transport in complex systems and for formulating and optimizing unconventional natural gas development strategies.展开更多
Currently,the solid adsorbents with porous structure have been widely applied in CO_(2)capture.However,the unmodified MgO-ZrO_(2)adsorbents appeared to be low adsorption capacity of CO_(2).The solid adsorbent material...Currently,the solid adsorbents with porous structure have been widely applied in CO_(2)capture.However,the unmodified MgO-ZrO_(2)adsorbents appeared to be low adsorption capacity of CO_(2).The solid adsorbent materials were successfully synthesized by loading TEPA onto the pore MgO/ZrO_(2)carriers in the paper.The pore structure and surface characteristic of the samples were analyzed by using XRD,BET,FT-IR and SEM.The adsorbent materials exhibited microcrystalline state,and the crystallinity of all samples gradually decreased as the increase of TEPA content.The pore structure analysis indicated that the modification of MgO-ZrO_(2)adsorbents with TEPA led to the decrease of the specific surface areas,but the narrow micro-mesopore size distributions ranging from 1.8-12 nm in the adsorbents still were maintained.FT-IR spectrum results further verified the successful loading of TEPA.The adsorption capacity of the adsorbents for CO_(2)were tested by using an adsorption apparatus equipped with gas chromatography.The results indicated that when the TEPA loading reached 50%,the sample exhibited the maximum adsorption value for CO_(2),reaching 4.07 mmol/g under the operation condition of 75℃and atmospheric pressure.This result could be assigned to not only the base active sites but also the coexistence of both micropore and mesopore in the adsorbent.After three cycles tests for CO_(2)capture,the adsorption value of the sample for CO_(2)can also reached 95%of its original adsorption capacity,which verified the excellent cyclic operation stability.展开更多
This paper demonstrates the strategic molecular design of functional polymer monoliths comprised of mesoporous fibers with stimuli-responsive Joule-heating properties for the rapid and efficient recovery of viscous fu...This paper demonstrates the strategic molecular design of functional polymer monoliths comprised of mesoporous fibers with stimuli-responsive Joule-heating properties for the rapid and efficient recovery of viscous fuel oil from water.The mesoporous fibers were composed of carefully selected monomers,which spontaneously entangled with each other to form a spongy monolith in a one-pot synthesis process.The subsequent addition of polypyrrole nanoparticles to the polymer produced superwettable intertwined fibers with strain-responsive conductivity,allowing the monolith to be used as a compressible,fibrous,and porous adsorbent with a high-flux separation capability and a tunable electrical heating effect.This adsorbent was demonstrated to successfully separate different types of low-viscosity oil from water in a continuous,highly efficient process.It also induced a rapid increase in the temperature during the recovery of marine fuel oil(MFO380),with a minimal compression of 3%under an external voltage.The proposed adsorbent can thus be used for the effective recovery of various fuel oils and improved further by incorporating other synergistic components for various water-treatment systems.展开更多
Lead(Pb)is a toxic metal found in wastewater,posing significant health risks to both humans and the environment.This study aimed to develop a novel adsorbent for lead removal from aqueous solutions.This adsorbent,a co...Lead(Pb)is a toxic metal found in wastewater,posing significant health risks to both humans and the environment.This study aimed to develop a novel adsorbent for lead removal from aqueous solutions.This adsorbent,a coffee husk extract-capped magnetite with pumice silica nanocomposite(CHE-capped M/PU/Si-NC),was synthesized using a completely green approach.The novelty of this study lies in the green synthesis of silica nanoparticles(SiO_(2)-NPs)throughout the process.Coffee husk extract(CHE)served as both a stabilizing and capping agent for the SiO_(2)-NPs,which were synthesized from sodium silicate(Na_(2)SiO_(3))extracted from bagasse ash(BA).Subsequently,the CHE-capped silica was co-precipitated with phyto-fabricated magnetite and integrated into a pumice matrix to produce the final CHE-capped M/PU/Si-NC adsorbent.The CHE-capped M/PU/Si-NC was characterized using SEM,XRF,FTIR,BET,XRD,TGA,and zeta potential analysis.The surface area of the CHE-capped M/PU/Si-NC was determined to be 313 m^(2)·g^(-1),and TGA results indicated good thermal stability up to 690℃.The zeta potential was measured at-37.7 mV.XRD analysis of CHE-capped M/PU/Si-NC confirmed the formation of magnetite and revealed its crystal structure.The maximum adsorption performance of this material was observed to be 95%at an adsorbent dosage of 2 g·L^(-1) and an initial Pb^(2+)concentration of 100 g·L^(-1).The adsorption kinetics were best described by the pseudo-second-order kinetic model.The Langmuir isotherm provided a good fit with a maximum adsorption capacity of 150 mg·g^(-1)(R^(2)=0.99).Regeneration studies demonstrated that the adsorbent maintained its high Pb^(2+) uptake capacity for up to five cycles.Overall,these findings suggest that this adsorbent is a promising candidate for the removal of Pb^(2+) from water and wastewater.展开更多
Boron adsorbents with high adsorption capacities have long been a focus of research for a long time.This study used small molecular polyols with different hydroxyl groups as functional monomers and as end-capping agen...Boron adsorbents with high adsorption capacities have long been a focus of research for a long time.This study used small molecular polyols with different hydroxyl groups as functional monomers and as end-capping agents,functional dendritic polyurethanes with nano structure were successfully prepared by one-pot method.The single molecule size and surface morphology were characterized by dynamic light scattering,transmission electron microscopy and scanning electron microscopy,and the molecular size in the dry state was 11 to 18 nm.The prepared materials were used as the boron adsorbents,and the effects of pH,time,boron solution concentration and temperature on the adsorption were studied.The results showed that the capacity of adsorbed boron could reach 110-130 mg·g^(-1).Adsorption was a homogeneous monolayer adsorption controlled by chemisorption,and adsorption thermodynamics showed that was a spontaneous endothermic process.Adsorption behavior was best described by the pseudo-second-order kinetic model and the Langmuir isotherm.This study also showed that it was difficult for ortho/meta-hydroxyl groups to chelate with H_(3)BO_(3) and other polyborates,and the chelates mainly had good chelating properties with B(OH)_(4)^(-),and the chelates formed had large steric hindrance.At the same time,increasing the number of hydroxyl groups of functional monomers was beneficial to increase the adsorption capacity of materials.In addition,the cyclic adsorption/desorption experiments showed that DPUs have good cyclic stability.At the same time,the adsorption results of the original salt lake brine showed that other metal ions in the brine had little effect on the adsorption of boron,and the adsorption capacity was as high as52.93 mg·g^(-1),and the maximum adsorption capacity was obtained by Adams-Bohart model to58.80 mg·g^(-1).The outstanding selectivity and adsorption capacity of these materials have broad potential application,and are expected to be used for the efficient adsorption and removal in boroncontaining water bodies.展开更多
This study introduced a microwave-assisted pyrolysis method for the rapid and efficientpreparation of boron-doped porous biochar. The resulting biochar exhibited a large specificsurface area (933.39 m^(2)/g), a rich p...This study introduced a microwave-assisted pyrolysis method for the rapid and efficientpreparation of boron-doped porous biochar. The resulting biochar exhibited a large specificsurface area (933.39 m^(2)/g), a rich porous structure (1.044 cm3/g), and abundant active sites.Consequently, the prepared boron-doped porous biochar exhibited higher efficiency in adsorbingtetracycline with a maximum adsorption capacity of 413.223 mg/g, which significantlyexceeded that of unmodified biochar andmost commercial and reported adsorbents.The correlation analysis between the adsorption capacity and adsorbent characteristics revealedthat the formation of the –BCO_(2) group enhanced π–π electron donor–acceptor interactionsbetween boron-doped porous biochar and tetracycline. This mechanism mainlycontributed to the enhanced adsorption of tetracycline by boron-doped porous biochar. Additionally,the as-prepared boron-doped porous biochar exhibited broad applications in removingantibiotics (tetracycline), phenolics (bisphenol A), and dyes (methylene blue andrhodamine B). Moreover, the boron-doped porous biochar exhibited satisfactory stability,and its adsorption capacity can be nearly completely regenerated through simple heat treatment.This study provides new insights into the effectiveness of boron-doped carbonaceousmaterials in removing antibiotic contaminants.展开更多
The manufacture and obsolescence of smartphones produce numerous waste plastic accessories(e.g.,waste smartphone protective film(WSPF)),possessing immense potential for recycling.However,available recycling technologi...The manufacture and obsolescence of smartphones produce numerous waste plastic accessories(e.g.,waste smartphone protective film(WSPF)),possessing immense potential for recycling.However,available recycling technologies have limitations such as substrate damage and secondary pollutant generation.The present study aimed to develop a green disposal method that not only recycled polyethylene terephthalate(PET)from WSPF,but also reused the stripped polyacrylate(PAA)adhesive as an adsorbent to reduce solid waste generation.When the WSPF was treated in 1 mol/L NaOH solution at 90°C,the PAA hydrolyzed to two main by-products of 1-butanol and 2-ethylhexanol,weakening the binding strength between PAA and PET and then efficient separation of them.Further bench-scale test revealed that over 97.2%of detachment efficiency toward PAA was achieved during continuous treatment of 17 batches of WSPF(200 g for each)without supplement of NaOH and generation of wastewater.Meanwhile,the economic evaluation indicated that the recycling method would generate a net profit margin of 647%for the second year without considering the incurrence of new cost and input.Additionally,the pyrolysis of waste PAA enabled its conversion into potential adsorbent,which showed 2 to 4 times enhanced adsorption capacity toward styrene and ethyl acetate after modification with NaOH solution.This study provides a green method for recycling waste plastics and inspires a referable solution for solid waste treatment in the smartphone industry.展开更多
Cu(I)based CO adsorbents are prone to oxidation and deactivation owing to the sensitivity of Cu^(+) ions to oxygen and moisture in the humid air.In this study,in order to improve its antioxidant performance,hydrophobi...Cu(I)based CO adsorbents are prone to oxidation and deactivation owing to the sensitivity of Cu^(+) ions to oxygen and moisture in the humid air.In this study,in order to improve its antioxidant performance,hydrophobic Cu(I)based adsorbents were fabricated using polytetrafluoroethylene(PTFE)for the hydrophobic modification,effectively avoiding the contact of CuCl active species with moisture,thereby inhibiting the oxidation of the Cu(I)based adsorbents.The successful introduction of PTFE into the activated carbon(AC)carrier significantly improves the hydrophobicity of the adsorbent.The optimal adsorbent CuCl(6)@AC-PTFE(0.10%)with the CuCl loading of 6 mmol·g^(-1)and the PTFE mass concentration of 0.10%exhibits an excellent CO adsorption capacity of 3.61 mmol·g^(-1)(303 K,500 kPa)as well as high CO/CO_(2)and CO/N_(2)adsorption selectivities of 29 and 203(303 K,100 kPa).Particularly,compared with the unmodified adsorbents,the antioxidant performance of modified adsorbent CuCl(6)@AC-PTFE(0.10%)is significantly improved,holding 86%of CO adsorption performance of fresh one after 24 h of exposure to humid air with a relative humidity of 70%,making the fabricated composite a promising adsorbent for CO separation.展开更多
The novel magnetic sepiolite/Fe_(3)O_(4)/zero-valent iron(nZVI)nanocomposite(nZVI@SepH-Mag)was prepared and used to achieve the removal of Cr(VI)in this work.The nZVI@SepH-Mag composites were characterized by XRD,FTIR...The novel magnetic sepiolite/Fe_(3)O_(4)/zero-valent iron(nZVI)nanocomposite(nZVI@SepH-Mag)was prepared and used to achieve the removal of Cr(VI)in this work.The nZVI@SepH-Mag composites were characterized by XRD,FTIR,BET,SEM and TEM.The characterization results indicated that the structure of the composite consisted of small nanoscale nZVI and magnetite(Mag)particles uniformly anchoring on the surface of acid-activated sepiolite(SepH).Batch experiments were used to analyze the effects of main factors on Cr(VI)removal.A 100%removal efficiency in 60 min and enhanced reaction ratio were reached by the composite comparing other existing materials.The kinetic of the adsorption and possible Cr(VI)removal mechanism of the hybrids were also evaluated and proposed.Based on the removal products identified by Raman,XRD and XPS,a reduction mechanism was proposed.The results indicated that the SepH and Mag can inhibit the agglomeration and enhance the dispersibility of nZVI,and Mag and nZVI displayed good synergetic effects.展开更多
Based on the test and experimental data from exploration well cores of the Upper Paleozoic in the central-eastern Ordos Basin,combined with structural,burial depth and fluid geochemistry analyses,this study reveals th...Based on the test and experimental data from exploration well cores of the Upper Paleozoic in the central-eastern Ordos Basin,combined with structural,burial depth and fluid geochemistry analyses,this study reveals the fluid characteristics,gas accumulation control factors and accumulation modes in the Upper Paleozoic coal reservoirs.The study indicates findings in two aspects.First,the 1500-1800 m interval represents the critical transition zone between open fluid system in shallow-medium depths and closed fluid system in deep depths.The reservoirs above 1500 m reflect intense water invasion,with discrete pressure gradient distribution,and the presence of methane mixed with varying degrees of secondary biogenic gas,and they generally exhibit high water saturation and adsorbed gas undersaturation.The reservoirs deeper than 1800 m,with extremely low permeability,are self-sealed,and contains closed fluid systems formed jointly by the hydrodynamic lateral blocking and tight caprock confinement.Within these systems,surface runoff infiltration is weak,the degree of secondary fluid transformation is minimal,and the pressure gradient is relatively uniform.The adsorbed gas saturation exceeds 100%in most seams,and the free gas content primarily ranges from 1 m^(3)/t to 8 m^(3)/t(greater than 10 m^(3)/t in some seams).Second,the gas accumulation in deep coals is primarily controlled by coal quality,reservoir-caprock assemblage,and structural position governed storage,wettability and sealing properties,under the constraints of the underground temperature and pressure conditions.High-rank,low-ash yield coals with limestone and mudstone caprocks show superior gas accumulation potential.Positive structural highs and wide and gentle negative structural lows are favorable sites for gas enrichment,while slope belts of fold limbs exhibit relatively lower gas content.This research enhances understanding of gas accumulation mechanisms in coal reservoirs and provides effective parameter reference for precise zone evaluation and innovation of adaptive stimulation technologies for deep resources.展开更多
Mercury(Hg)pollution has been a global concern in recent decades,posing a significant threat to entire ecosystems and human health due to its cumulative toxicity,persistence,and transport in the atmosphere.The intense...Mercury(Hg)pollution has been a global concern in recent decades,posing a significant threat to entire ecosystems and human health due to its cumulative toxicity,persistence,and transport in the atmosphere.The intense interaction between mercury and selenium has opened up a new field for studying mercury removal from industrial flue gas pollutants.Besides the advantages of good Hg^(0) capture performance and lowsecondary pollution of the mineral selenium compounds,the most noteworthy is the relatively low regeneration temperature,allowing adsorbent regeneration with low energy consumption,thus reducing the utilization cost and enabling recovery of mercury resources.This paper reviews the recent progress of mineral selenium compounds in flue gas mercury removal,introduces in detail the different types ofmineral selenium compounds studied in the field ofmercury removal,reviews the adsorption performance of various mineral selenium compounds adsorbents on mercury and the influence of flue gas components,such as reaction temperature,air velocity,and other factors,and summarizes the adsorption mechanism of different fugitive forms of selenium species.Based on the current research progress,future studies should focus on the economic performance and the performance of different carriers and sizes of adsorbents for the removal of Hg^(0) and the correlation between the gas-particle flow characteristics and gas phase mass transfer with the performance of Hg^(0) removal in practical industrial applications.In addition,it remains a challenge to distinguish the oxidation and adsorption of Hg^(0) quantitatively.展开更多
The indiscriminate use and disposal of ciprofloxacin(CIP)have led to its detection in water globally,which pose a huge risk to public health and water environment.Herein,(Zn-Al)LDHs modified 3D reduced graphene oxide ...The indiscriminate use and disposal of ciprofloxacin(CIP)have led to its detection in water globally,which pose a huge risk to public health and water environment.Herein,(Zn-Al)LDHs modified 3D reduced graphene oxide nanocomposite((Zn-Al)LDHs/3D-rGO)was synthesized through a feasible onepot hydrothermal method for CIP removal.The highly distributed(Zn-Al)LDHs flakes on the surface of 3D-rGO endow the resulted(Zn-Al)LDHs/3D-rGO with an excellent adsorption performance for CIP.The adsorption results showed that the adsorption process could be well interpreted by Temkin isothermal model and the pseudo second-order kinetics model.The maximal adsorption capacity of 20.01 mg·g^(-1)for CIP could be achieved under the optimal conditions optimized by response surface methodology(RSM).The inhibitory effect of co-existing ions on CIP adsorption were also discussed.The probable adsorption mechanism might be ascribed toπ-πinteractions,hydrogen bonding,electrostatic,and surface complexation.Regeneration tests showed that the obtained 3D porous material also possessed pronounced recyclability.The obtained(Zn-Al)LDHs/3D-rGO holds a great potential for removal of CIP from actual wastewater.展开更多
Geological samples often contain significant amounts of iron,which,although not typically the target element,can substantially interfere with the analysis of other elements of interest.To mitigate these interferences,...Geological samples often contain significant amounts of iron,which,although not typically the target element,can substantially interfere with the analysis of other elements of interest.To mitigate these interferences,amidoximebased radiation grafted adsorbents have been identified as effective for iron removal.In this study,an amidoximefunctionalized,radiation-grafted adsorbent synthesized from polypropylene waste(PPw-g-AO-10)was employed to remove iron from leached geological samples.The adsorption process was systematically optimized by investigating the effects of pH,contact time,adsorbent dosage,and initial ferric ion concentration.Under optimal conditions-pH1.4,a contact time of 90 min,and an initial ferric ion concentration of 4500 mg/L-the adsorbent exhibited a maximum iron adsorption capacity of 269.02 mg/g.After optimizing the critical adsorption parameters,the adsorbent was applied to the leached geological samples,achieving a 91%removal of the iron content.The adsorbent was regenerated through two consecutive cycles using 0.2 N HNO_(3),achieving a regeneration efficiency of 65%.These findings confirm the efficacy of the synthesized PPw-g-AO-10 as a cost-effective and eco-friendly adsorbent for successfully removing iron from leached geological matrices while maintaining a reasonable degree of reusability.展开更多
Persistently high arsenic levels in drinkingwater threaten underprivileged areas worldwide.Although nanomaterials exhibit exceptional arsenic removal properties,their implementation presents challenges.We converted N-...Persistently high arsenic levels in drinkingwater threaten underprivileged areas worldwide.Although nanomaterials exhibit exceptional arsenic removal properties,their implementation presents challenges.We converted N-methylimidazole-modified polyvinyl chloride into a granular anion exchange resin(PNAXRs)using an environmentally friendly and gentle synthesis method.Additionally,a unified approach for embedding nanomaterials within these resins was proposed,yielding a TiO_(2) composite resin(TiO_(2)@PNAXRs).Structural characterization confirmed the successful grafting of imidazolium cations with anion-exchange properties onto polyvinyl chloride side chains.BET analysis indicates a high specific surface area of 70.31 m^(2)/g for the PNAXRs.TGA curves demonstrate the successful encapsulation of approximately 24.9%TiO_(2) within the composite resin.The SEM-EDS results show a uniform distribution of TiO_(2) in the PNAXRs,which facilitates the effective utilization of TiO_(2).Adsorption experiments in conjunction with XPS analysis provided insights into the dual role of inner-sphere complexation and ion exchange in the adsorption mechanism of As(V)by TiO_(2)@PNAXRs.In dynamic adsorption tests utilizing high-As(V)groundwater from the Datong Basin as the influent,TiO_(2)@PNAXRs demonstrated the ability to produce effluents that meet the World Health Organization’s recommended limit for arsenic in drinking water,with a capacity of 1780 bed volumes.These findings support the use of PNAXRs as ideal matrices for TiO_(2) and their practical application in As(V)removal processes.展开更多
Maintaining high metal dispersion of supported metal catalysts to achieve superior reactivity under harsh conditions poses one of the main challenges for their practical applications.Constructing and regulating the st...Maintaining high metal dispersion of supported metal catalysts to achieve superior reactivity under harsh conditions poses one of the main challenges for their practical applications.Constructing and regulating the strong metal-support interactions(SMSI)by diverse methodologies has emerged as one of the promising approaches to fabricating robust supported metal catalysts.In this study,we report an L-ascorbic acid(AA)-inducing strategy to generate SMSI on a titania-supported gold(Au)catalyst after high-temperature treatment in an inert atmosphere(600℃,N_(2)).The AA-induced SMSI can efficiently stabilize Au nanoparticles(NPs)and preserve their catalytic performance.The detailed study reveals that the key to realizing this SMSI is the generation of oxygen vacancies within the TiO_(2) support induced by the adsorbed AA,which drives the formation of the Ti Oxpermeable layer onto the Au NPs.The strategy could be extended to TiO_(2)-supported Au catalysts with different crystal phases and platinum group metals,such as Pt,Pd,and Rh.This work offers a promising novel route to design stable and efficient supported noble metal catalysts by constructing SMSI using simple reducing organic adsorbent.展开更多
基金supported by the National Natural Science Foundation of China(no.22372154,21972131).
文摘Despite substantial efforts in developing high-performance catalysts for the oxygen reduction reaction(ORR),the persistent challenge lies in the high onset overpotential of the ORR,and the effect of the elec-trolyte solution cannot be ignored.Consequently,we have systematically investigated the impact of adsorbate species and concentration,as well as solution pH,on the ORR activity on Pt(111)and Pt(poly)electrodes.The results all tend to establish a linear quantitative relationship between the onset potential for ORR and the adsorption equilibrium potential of the adsorbate.This finding indicates the decisive role of adsorbates in the onset potential for ORR,suggesting that the adsorption potential of adsorbates can serve as an intuitive criterion for ORR activity.Additional support for this conclusion is derived from experimental results obtained from the oxygen evolution reaction on Pt(poly)with different adsorbate species and from the hydrogen evolution reaction on Pt(111)with iodine adsorption.We further propose both an empirical equation for the onset potential for ORR and the concept of a potential-regulated adsor-bate shielding effect to elucidate the influence of adsorbates on ORR activity.This study provides new insights into the high onset overpotential of the ORR and offers potential strategies for predicting and enhancingORRactivity inthefuture.
文摘Characterization of electric properties of nanomaterials usually involves fabricating field effect transistors （FET） and deriving materials properties from device performances. However, the quality of electrode contacts in FET devices heavily influences the device performance, which makes it difficult to obtain the intrinsic electric properties of nanomaterials. Dielectric force microscopy （DFM）, a contactless method developed recently, can detect the low-frequency dielectric responses of nanomaterials without electric contact, which avoids the influence of electric contact and can be used to study the intrinsic conductivity of nanomaterials. Here we study the influences of surface adsorbates on the conductivity of ZnO nanowires （NWs） by using FET and DFM methods. The conductivity of ZnO NW is much larger in N2 atmosphere than that in ambient environment as measured by FET device, which is further proven by DFM measurement that the ZnO NW exhibits larger dielectric response in N2 environment, and the influence of electrode contacts on measurement can be ruled out. Based on these results, it can be concluded that the adsorbates on ZnO NW surface highly influence the conductivity of ZnO NW rather than the electrode contact. This work also verifies the capability of DFM in measuring electric properties of nanomaterials.
基金supported by the Elements Strategy Initiative for Catalysts and Batteries (ESICB)a Grant-in-Aid for Scientific Research (26248003, 15H01042) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan
文摘The mass spectrometry of gold clusters stabilized by poly（N‐vinyl‐2‐pyrrolidone） （Au：PVP） re‐vealed the presence of Cl adsorbates derived from synthetic precursors, mainly on the Au34 and Au43 clusters. Changes in the amount of Cl adsorbates on the Au clusters did not affect the catalytic prop‐erties for the aerobic oxidation of benzyl alcohol, suggesting that the Cl atoms were only weakly bound to the Au clusters. In contrast, the replacement of Cl with Br on the Au34 and Au43 clusters significantly suppressed activity, without any influence on the electronic structure. This result indi‐cated that the Br atoms were strongly bound to the Au clusters and sterically blocked their active sites. The substantial reduction of the catalytic activity by the Br adsorbates suggested that the Au34 and Au43 clusters made a major contribution to the catalytic activity of the Au：PVP.
基金supported by the National Natural Science Foundation of China(22102132)the Funds for Basic Scientific Research in Central Universities+2 种基金the Scientific Research Foundation of Qingdao UniversityTaishan Scholar Program(NO.tsqnz20231213)sponsored by the Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(CX2024101)。
文摘Platinum group alloys have an excellent electronic structure for oxidation of alcohols,but the active sites are more susceptible to deactivation by CO adsorbates(CO_(ads)).The precise integration of single-atom and alloy structures is highly attractive for energy conversion but still a challenge.Here,we report an ionexchange coupled in situ reduction strategy to fabricate hollow PtPdTe alloy nanoreactors loaded with atomically dispersed Cu sites(Cu_(SA)/h-PtPdTe NRs).The planted oxyphilic Cu single sites and resulted compressive strains are conductive to modulating the electronic structure of the active sites,which changes the rate-determining step of the reaction while inhibiting the formation of CO_(ads)and modulating the adsorption of intermediates,resulting in the improved activity and stability.Specifically,the obtained Cu_(SA)/h-PtPdTe NRs exhibit an excellent oxidation performance of multiple alcohols,especially for methanol and ethanol,with 8.0 and 10.3 times of the mass activity higher than Pt/C,and the activity could be recovered by refreshing the electrolyte and could be sustained for 72,000 and 36,000 s,respectively.Meanwhile,Cu_(SA)/h-PtPdTe NRs show superior oxidation performance and durability to ethylene glycol and glycerol.This work pioneers the realization of precise modulation of catalytic sites using single atoms and provides an encouraging pathway for the design of efficient and stable electrocatalysts for the oxidation of multiple alcohols,which could broaden the range of options and sources of fuel cells.
基金supported by the Ministry of Science and Technology(2016YFA0203302)the National Natural Science Foundation of China(21875042,21634003,51573027 and 11227902)+3 种基金Science and Technology Commission of Shanghai Municipality(16JC1400702 and 18QA1400800)Shanghai Municipal Education Commission(2017-01-07-00-07-E00062)Yanchang Petroleum Groupthe Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning。
文摘Developing efficient electrocatalysts for the oxygen evolution reaction(OER)under neutral conditions is important for microbial electrolysis cells(MECs).However,the OER kinetics in neutral electrolytes at present are extremely sluggish,resulting in high overpotentials that greatly limit the energy conversion efficiencies of MECs.Previous studies failed to probe the adsorbates on surface metal sites of catalysts at the atomic scale and elucidate their influence on the catalytic activities,which has impeded the rational design of efficient neutral OER catalysts with optimal surface structures.Here,using in situ transmission electron microscopy(TEM),in situ X-ray photoelectron spectroscopy(XPS)and in situ low-energy ion scattering studies,we have identified,for the first time,that the electrochemically activated adsorbates on surface metal sites play a critical role in boosting the neutral OER activities of Ru-Ir binary oxide(RuxIryO2)catalysts.The adsorbate-activated RuxIryO2on a glassy carbon electrode achieved a low overpotential of 324 m V at10 m A cm-2in neutral electrolyte,with a 36-fold improvement in turnover frequency compared with that of Ir O2benchmark.Upon application in an MEC system,the resulting full cell showed a decreased voltage of 1.8 V,200 m V lower than the best value reported to date,facilitating efficient synthesis of poly(3-hydroxybutyrate)from bioelectrochemical CO2reduction.Density functional theory(DFT)studies revealed that the enhanced OER activity of RuxIryO2catalyst arose from local structural distortion of adjacent adsorbate-covered Ru octahedra at the catalyst surface and the consequently decreased adsorption energies of OER intermediates on Ir active center.
基金supported by the Natural Science Foundation of China(Grant No.42302170)National Postdoctoral Innovative Talent Support Program(Grant No.BX20220062)+3 种基金CNPC Innovation Found(Grant No.2022DQ02-0104)National Science Foundation of Heilongjiang Province of China(Grant No.YQ2023D001)Postdoctoral Science Foundation of Heilongjiang Province of China(Grant No.LBH-Z22091)the Natural Science Foundation of Shandong Province(Grant No.ZR2022YQ30).
文摘Prediction of production decline and evaluation of the adsorbed/free gas ratio are critical for determining the lifespan and production status of shale gas wells.Traditional production prediction methods have some shortcomings because of the low permeability and tightness of shale,complex gas flow behavior of multi-scale gas transport regions and multiple gas transport mechanism superpositions,and complex and variable production regimes of shale gas wells.Recent research has demonstrated the existence of a multi-stage isotope fractionation phenomenon during shale gas production,with the fractionation characteristics of each stage associated with the pore structure,gas in place(GIP),adsorption/desorption,and gas production process.This study presents a new approach for estimating shale gas well production and evaluating the adsorbed/free gas ratio throughout production using isotope fractionation techniques.A reservoir-scale carbon isotope fractionation(CIF)model applicable to the production process of shale gas wells was developed for the first time in this research.In contrast to the traditional model,this model improves production prediction accuracy by simultaneously fitting the gas production rate and δ^(13)C_(1) data and provides a new evaluation method of the adsorbed/free gas ratio during shale gas production.The results indicate that the diffusion and adsorption/desorption properties of rock,bottom-hole flowing pressure(BHP)of gas well,and multi-scale gas transport regions of the reservoir all affect isotope fractionation,with the diffusion and adsorption/desorption parameters of rock having the greatest effect on isotope fractionation being D∗/D,PL,VL,α,and others in that order.We effectively tested the universality of the four-stage isotope fractionation feature and revealed a unique isotope fractionation mechanism caused by the superimposed coupling of multi-scale gas transport regions during shale gas well production.Finally,we applied the established CIF model to a shale gas well in the Sichuan Basin,China,and calculated the estimated ultimate recovery(EUR)of the well to be 3.33×10^(8) m^(3);the adsorbed gas ratio during shale gas production was 1.65%,10.03%,and 23.44%in the first,fifth,and tenth years,respectively.The findings are significant for understanding the isotope fractionation mechanism during natural gas transport in complex systems and for formulating and optimizing unconventional natural gas development strategies.
基金supported by Shanxi Provincial Key Research and Development Project(202102090301026)Graduate Education Innovation Project of Taiyuan University of Science and Technology(SY2023024)。
文摘Currently,the solid adsorbents with porous structure have been widely applied in CO_(2)capture.However,the unmodified MgO-ZrO_(2)adsorbents appeared to be low adsorption capacity of CO_(2).The solid adsorbent materials were successfully synthesized by loading TEPA onto the pore MgO/ZrO_(2)carriers in the paper.The pore structure and surface characteristic of the samples were analyzed by using XRD,BET,FT-IR and SEM.The adsorbent materials exhibited microcrystalline state,and the crystallinity of all samples gradually decreased as the increase of TEPA content.The pore structure analysis indicated that the modification of MgO-ZrO_(2)adsorbents with TEPA led to the decrease of the specific surface areas,but the narrow micro-mesopore size distributions ranging from 1.8-12 nm in the adsorbents still were maintained.FT-IR spectrum results further verified the successful loading of TEPA.The adsorption capacity of the adsorbents for CO_(2)were tested by using an adsorption apparatus equipped with gas chromatography.The results indicated that when the TEPA loading reached 50%,the sample exhibited the maximum adsorption value for CO_(2),reaching 4.07 mmol/g under the operation condition of 75℃and atmospheric pressure.This result could be assigned to not only the base active sites but also the coexistence of both micropore and mesopore in the adsorbent.After three cycles tests for CO_(2)capture,the adsorption value of the sample for CO_(2)can also reached 95%of its original adsorption capacity,which verified the excellent cyclic operation stability.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(no.2022R1C1C1003149 and 2020R1A5A8018367)by the Korea Institute of Marine Science&Technology Promotion(KIMST)funded by the Ministry of Oceans and Fisheries,Korea(00254781)This research was alsosupported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(no.RS-202400345266)。
文摘This paper demonstrates the strategic molecular design of functional polymer monoliths comprised of mesoporous fibers with stimuli-responsive Joule-heating properties for the rapid and efficient recovery of viscous fuel oil from water.The mesoporous fibers were composed of carefully selected monomers,which spontaneously entangled with each other to form a spongy monolith in a one-pot synthesis process.The subsequent addition of polypyrrole nanoparticles to the polymer produced superwettable intertwined fibers with strain-responsive conductivity,allowing the monolith to be used as a compressible,fibrous,and porous adsorbent with a high-flux separation capability and a tunable electrical heating effect.This adsorbent was demonstrated to successfully separate different types of low-viscosity oil from water in a continuous,highly efficient process.It also induced a rapid increase in the temperature during the recovery of marine fuel oil(MFO380),with a minimal compression of 3%under an external voltage.The proposed adsorbent can thus be used for the effective recovery of various fuel oils and improved further by incorporating other synergistic components for various water-treatment systems.
文摘Lead(Pb)is a toxic metal found in wastewater,posing significant health risks to both humans and the environment.This study aimed to develop a novel adsorbent for lead removal from aqueous solutions.This adsorbent,a coffee husk extract-capped magnetite with pumice silica nanocomposite(CHE-capped M/PU/Si-NC),was synthesized using a completely green approach.The novelty of this study lies in the green synthesis of silica nanoparticles(SiO_(2)-NPs)throughout the process.Coffee husk extract(CHE)served as both a stabilizing and capping agent for the SiO_(2)-NPs,which were synthesized from sodium silicate(Na_(2)SiO_(3))extracted from bagasse ash(BA).Subsequently,the CHE-capped silica was co-precipitated with phyto-fabricated magnetite and integrated into a pumice matrix to produce the final CHE-capped M/PU/Si-NC adsorbent.The CHE-capped M/PU/Si-NC was characterized using SEM,XRF,FTIR,BET,XRD,TGA,and zeta potential analysis.The surface area of the CHE-capped M/PU/Si-NC was determined to be 313 m^(2)·g^(-1),and TGA results indicated good thermal stability up to 690℃.The zeta potential was measured at-37.7 mV.XRD analysis of CHE-capped M/PU/Si-NC confirmed the formation of magnetite and revealed its crystal structure.The maximum adsorption performance of this material was observed to be 95%at an adsorbent dosage of 2 g·L^(-1) and an initial Pb^(2+)concentration of 100 g·L^(-1).The adsorption kinetics were best described by the pseudo-second-order kinetic model.The Langmuir isotherm provided a good fit with a maximum adsorption capacity of 150 mg·g^(-1)(R^(2)=0.99).Regeneration studies demonstrated that the adsorbent maintained its high Pb^(2+) uptake capacity for up to five cycles.Overall,these findings suggest that this adsorbent is a promising candidate for the removal of Pb^(2+) from water and wastewater.
基金financially supported by Applied Basic Research Project of Qinghai province(2023-ZJ-774)。
文摘Boron adsorbents with high adsorption capacities have long been a focus of research for a long time.This study used small molecular polyols with different hydroxyl groups as functional monomers and as end-capping agents,functional dendritic polyurethanes with nano structure were successfully prepared by one-pot method.The single molecule size and surface morphology were characterized by dynamic light scattering,transmission electron microscopy and scanning electron microscopy,and the molecular size in the dry state was 11 to 18 nm.The prepared materials were used as the boron adsorbents,and the effects of pH,time,boron solution concentration and temperature on the adsorption were studied.The results showed that the capacity of adsorbed boron could reach 110-130 mg·g^(-1).Adsorption was a homogeneous monolayer adsorption controlled by chemisorption,and adsorption thermodynamics showed that was a spontaneous endothermic process.Adsorption behavior was best described by the pseudo-second-order kinetic model and the Langmuir isotherm.This study also showed that it was difficult for ortho/meta-hydroxyl groups to chelate with H_(3)BO_(3) and other polyborates,and the chelates mainly had good chelating properties with B(OH)_(4)^(-),and the chelates formed had large steric hindrance.At the same time,increasing the number of hydroxyl groups of functional monomers was beneficial to increase the adsorption capacity of materials.In addition,the cyclic adsorption/desorption experiments showed that DPUs have good cyclic stability.At the same time,the adsorption results of the original salt lake brine showed that other metal ions in the brine had little effect on the adsorption of boron,and the adsorption capacity was as high as52.93 mg·g^(-1),and the maximum adsorption capacity was obtained by Adams-Bohart model to58.80 mg·g^(-1).The outstanding selectivity and adsorption capacity of these materials have broad potential application,and are expected to be used for the efficient adsorption and removal in boroncontaining water bodies.
基金supported by the National Natural Science Foundation of China(Nos.52100062,and 52230001)China Postdoctoral Science Foundation(No.2023M732785).
文摘This study introduced a microwave-assisted pyrolysis method for the rapid and efficientpreparation of boron-doped porous biochar. The resulting biochar exhibited a large specificsurface area (933.39 m^(2)/g), a rich porous structure (1.044 cm3/g), and abundant active sites.Consequently, the prepared boron-doped porous biochar exhibited higher efficiency in adsorbingtetracycline with a maximum adsorption capacity of 413.223 mg/g, which significantlyexceeded that of unmodified biochar andmost commercial and reported adsorbents.The correlation analysis between the adsorption capacity and adsorbent characteristics revealedthat the formation of the –BCO_(2) group enhanced π–π electron donor–acceptor interactionsbetween boron-doped porous biochar and tetracycline. This mechanism mainlycontributed to the enhanced adsorption of tetracycline by boron-doped porous biochar. Additionally,the as-prepared boron-doped porous biochar exhibited broad applications in removingantibiotics (tetracycline), phenolics (bisphenol A), and dyes (methylene blue andrhodamine B). Moreover, the boron-doped porous biochar exhibited satisfactory stability,and its adsorption capacity can be nearly completely regenerated through simple heat treatment.This study provides new insights into the effectiveness of boron-doped carbonaceousmaterials in removing antibiotic contaminants.
基金supported by the National Natural Science Foundation of China(No.42177354)Guangzhou Basic and Applied Basic Research Scheme(No.2024A04J6358)the National Key R&D Program of China(No.2019YFC0214402).
文摘The manufacture and obsolescence of smartphones produce numerous waste plastic accessories(e.g.,waste smartphone protective film(WSPF)),possessing immense potential for recycling.However,available recycling technologies have limitations such as substrate damage and secondary pollutant generation.The present study aimed to develop a green disposal method that not only recycled polyethylene terephthalate(PET)from WSPF,but also reused the stripped polyacrylate(PAA)adhesive as an adsorbent to reduce solid waste generation.When the WSPF was treated in 1 mol/L NaOH solution at 90°C,the PAA hydrolyzed to two main by-products of 1-butanol and 2-ethylhexanol,weakening the binding strength between PAA and PET and then efficient separation of them.Further bench-scale test revealed that over 97.2%of detachment efficiency toward PAA was achieved during continuous treatment of 17 batches of WSPF(200 g for each)without supplement of NaOH and generation of wastewater.Meanwhile,the economic evaluation indicated that the recycling method would generate a net profit margin of 647%for the second year without considering the incurrence of new cost and input.Additionally,the pyrolysis of waste PAA enabled its conversion into potential adsorbent,which showed 2 to 4 times enhanced adsorption capacity toward styrene and ethyl acetate after modification with NaOH solution.This study provides a green method for recycling waste plastics and inspires a referable solution for solid waste treatment in the smartphone industry.
基金supported by the Natural Science Foundation of Shandong Province(ZR2021MB135)the Major Scientific and Technological Innovation Project of Shandong Province(2021ZDSYS13).
文摘Cu(I)based CO adsorbents are prone to oxidation and deactivation owing to the sensitivity of Cu^(+) ions to oxygen and moisture in the humid air.In this study,in order to improve its antioxidant performance,hydrophobic Cu(I)based adsorbents were fabricated using polytetrafluoroethylene(PTFE)for the hydrophobic modification,effectively avoiding the contact of CuCl active species with moisture,thereby inhibiting the oxidation of the Cu(I)based adsorbents.The successful introduction of PTFE into the activated carbon(AC)carrier significantly improves the hydrophobicity of the adsorbent.The optimal adsorbent CuCl(6)@AC-PTFE(0.10%)with the CuCl loading of 6 mmol·g^(-1)and the PTFE mass concentration of 0.10%exhibits an excellent CO adsorption capacity of 3.61 mmol·g^(-1)(303 K,500 kPa)as well as high CO/CO_(2)and CO/N_(2)adsorption selectivities of 29 and 203(303 K,100 kPa).Particularly,compared with the unmodified adsorbents,the antioxidant performance of modified adsorbent CuCl(6)@AC-PTFE(0.10%)is significantly improved,holding 86%of CO adsorption performance of fresh one after 24 h of exposure to humid air with a relative humidity of 70%,making the fabricated composite a promising adsorbent for CO separation.
基金Projects(52474138,52104261,52525401)supported by the National Natural Science Foundation of ChinaProject supported by the New Cornerstone Science Foundation through the XPLORER PRIZE,ChinaProject supported by the Shanxi Key Laboratory Funds of Mine Rock Strata Control and Disaster Prevention,China。
文摘The novel magnetic sepiolite/Fe_(3)O_(4)/zero-valent iron(nZVI)nanocomposite(nZVI@SepH-Mag)was prepared and used to achieve the removal of Cr(VI)in this work.The nZVI@SepH-Mag composites were characterized by XRD,FTIR,BET,SEM and TEM.The characterization results indicated that the structure of the composite consisted of small nanoscale nZVI and magnetite(Mag)particles uniformly anchoring on the surface of acid-activated sepiolite(SepH).Batch experiments were used to analyze the effects of main factors on Cr(VI)removal.A 100%removal efficiency in 60 min and enhanced reaction ratio were reached by the composite comparing other existing materials.The kinetic of the adsorption and possible Cr(VI)removal mechanism of the hybrids were also evaluated and proposed.Based on the removal products identified by Raman,XRD and XPS,a reduction mechanism was proposed.The results indicated that the SepH and Mag can inhibit the agglomeration and enhance the dispersibility of nZVI,and Mag and nZVI displayed good synergetic effects.
基金Supported by the National Natural Science Foundation of China(42130802,42272200)CNPC Science and Technology Major Project(2023ZZ18)+1 种基金PetroChina Changqing Oilfield Major Science and Technology Project(2023DZZ01)Technology Project of PetroChina Coalbed Methane Company Limited(2023-KJ-18)。
文摘Based on the test and experimental data from exploration well cores of the Upper Paleozoic in the central-eastern Ordos Basin,combined with structural,burial depth and fluid geochemistry analyses,this study reveals the fluid characteristics,gas accumulation control factors and accumulation modes in the Upper Paleozoic coal reservoirs.The study indicates findings in two aspects.First,the 1500-1800 m interval represents the critical transition zone between open fluid system in shallow-medium depths and closed fluid system in deep depths.The reservoirs above 1500 m reflect intense water invasion,with discrete pressure gradient distribution,and the presence of methane mixed with varying degrees of secondary biogenic gas,and they generally exhibit high water saturation and adsorbed gas undersaturation.The reservoirs deeper than 1800 m,with extremely low permeability,are self-sealed,and contains closed fluid systems formed jointly by the hydrodynamic lateral blocking and tight caprock confinement.Within these systems,surface runoff infiltration is weak,the degree of secondary fluid transformation is minimal,and the pressure gradient is relatively uniform.The adsorbed gas saturation exceeds 100%in most seams,and the free gas content primarily ranges from 1 m^(3)/t to 8 m^(3)/t(greater than 10 m^(3)/t in some seams).Second,the gas accumulation in deep coals is primarily controlled by coal quality,reservoir-caprock assemblage,and structural position governed storage,wettability and sealing properties,under the constraints of the underground temperature and pressure conditions.High-rank,low-ash yield coals with limestone and mudstone caprocks show superior gas accumulation potential.Positive structural highs and wide and gentle negative structural lows are favorable sites for gas enrichment,while slope belts of fold limbs exhibit relatively lower gas content.This research enhances understanding of gas accumulation mechanisms in coal reservoirs and provides effective parameter reference for precise zone evaluation and innovation of adaptive stimulation technologies for deep resources.
基金supported by the Basic Research Business Fund Grant Program for University of Science and Technology Beijing (No.06500227)the Fundamental Research Funds for the Central Universities (No.FRF-TP-22-091A1).
文摘Mercury(Hg)pollution has been a global concern in recent decades,posing a significant threat to entire ecosystems and human health due to its cumulative toxicity,persistence,and transport in the atmosphere.The intense interaction between mercury and selenium has opened up a new field for studying mercury removal from industrial flue gas pollutants.Besides the advantages of good Hg^(0) capture performance and lowsecondary pollution of the mineral selenium compounds,the most noteworthy is the relatively low regeneration temperature,allowing adsorbent regeneration with low energy consumption,thus reducing the utilization cost and enabling recovery of mercury resources.This paper reviews the recent progress of mineral selenium compounds in flue gas mercury removal,introduces in detail the different types ofmineral selenium compounds studied in the field ofmercury removal,reviews the adsorption performance of various mineral selenium compounds adsorbents on mercury and the influence of flue gas components,such as reaction temperature,air velocity,and other factors,and summarizes the adsorption mechanism of different fugitive forms of selenium species.Based on the current research progress,future studies should focus on the economic performance and the performance of different carriers and sizes of adsorbents for the removal of Hg^(0) and the correlation between the gas-particle flow characteristics and gas phase mass transfer with the performance of Hg^(0) removal in practical industrial applications.In addition,it remains a challenge to distinguish the oxidation and adsorption of Hg^(0) quantitatively.
基金support from Basic research project of Education Department of Liaoning Province(LJKZ0256)Special Fund for Basic Scientific Research of Liaoning Province(LJKZSYLUGX027).
文摘The indiscriminate use and disposal of ciprofloxacin(CIP)have led to its detection in water globally,which pose a huge risk to public health and water environment.Herein,(Zn-Al)LDHs modified 3D reduced graphene oxide nanocomposite((Zn-Al)LDHs/3D-rGO)was synthesized through a feasible onepot hydrothermal method for CIP removal.The highly distributed(Zn-Al)LDHs flakes on the surface of 3D-rGO endow the resulted(Zn-Al)LDHs/3D-rGO with an excellent adsorption performance for CIP.The adsorption results showed that the adsorption process could be well interpreted by Temkin isothermal model and the pseudo second-order kinetics model.The maximal adsorption capacity of 20.01 mg·g^(-1)for CIP could be achieved under the optimal conditions optimized by response surface methodology(RSM).The inhibitory effect of co-existing ions on CIP adsorption were also discussed.The probable adsorption mechanism might be ascribed toπ-πinteractions,hydrogen bonding,electrostatic,and surface complexation.Regeneration tests showed that the obtained 3D porous material also possessed pronounced recyclability.The obtained(Zn-Al)LDHs/3D-rGO holds a great potential for removal of CIP from actual wastewater.
文摘Geological samples often contain significant amounts of iron,which,although not typically the target element,can substantially interfere with the analysis of other elements of interest.To mitigate these interferences,amidoximebased radiation grafted adsorbents have been identified as effective for iron removal.In this study,an amidoximefunctionalized,radiation-grafted adsorbent synthesized from polypropylene waste(PPw-g-AO-10)was employed to remove iron from leached geological samples.The adsorption process was systematically optimized by investigating the effects of pH,contact time,adsorbent dosage,and initial ferric ion concentration.Under optimal conditions-pH1.4,a contact time of 90 min,and an initial ferric ion concentration of 4500 mg/L-the adsorbent exhibited a maximum iron adsorption capacity of 269.02 mg/g.After optimizing the critical adsorption parameters,the adsorbent was applied to the leached geological samples,achieving a 91%removal of the iron content.The adsorbent was regenerated through two consecutive cycles using 0.2 N HNO_(3),achieving a regeneration efficiency of 65%.These findings confirm the efficacy of the synthesized PPw-g-AO-10 as a cost-effective and eco-friendly adsorbent for successfully removing iron from leached geological matrices while maintaining a reasonable degree of reusability.
基金supported by the Key Research and Development Plan of Zhejiang Province(No.2021C03176)the National Key Research and Development Program of China(No.2022YFC3703700).
文摘Persistently high arsenic levels in drinkingwater threaten underprivileged areas worldwide.Although nanomaterials exhibit exceptional arsenic removal properties,their implementation presents challenges.We converted N-methylimidazole-modified polyvinyl chloride into a granular anion exchange resin(PNAXRs)using an environmentally friendly and gentle synthesis method.Additionally,a unified approach for embedding nanomaterials within these resins was proposed,yielding a TiO_(2) composite resin(TiO_(2)@PNAXRs).Structural characterization confirmed the successful grafting of imidazolium cations with anion-exchange properties onto polyvinyl chloride side chains.BET analysis indicates a high specific surface area of 70.31 m^(2)/g for the PNAXRs.TGA curves demonstrate the successful encapsulation of approximately 24.9%TiO_(2) within the composite resin.The SEM-EDS results show a uniform distribution of TiO_(2) in the PNAXRs,which facilitates the effective utilization of TiO_(2).Adsorption experiments in conjunction with XPS analysis provided insights into the dual role of inner-sphere complexation and ion exchange in the adsorption mechanism of As(V)by TiO_(2)@PNAXRs.In dynamic adsorption tests utilizing high-As(V)groundwater from the Datong Basin as the influent,TiO_(2)@PNAXRs demonstrated the ability to produce effluents that meet the World Health Organization’s recommended limit for arsenic in drinking water,with a capacity of 1780 bed volumes.These findings support the use of PNAXRs as ideal matrices for TiO_(2) and their practical application in As(V)removal processes.
基金supported by the National Natural Science Foundation of China(NSFC)the Japan Society for the Promotion of Science(JSPS)under the Joint Research Program(Nos.NSFC21961142006 and JPJSJRP20191804)+3 种基金NSFC(Nos.U22A20394 and 22375200)the DICP.CAS-Cardiff Joint Research Units(No.121421ZYLH20230008)the International Partnership Program of Chinese Academy of Sciences(No.028GJHZ2023097GC)the China Postdoctoral Science Foundation(No.2022M723086)。
文摘Maintaining high metal dispersion of supported metal catalysts to achieve superior reactivity under harsh conditions poses one of the main challenges for their practical applications.Constructing and regulating the strong metal-support interactions(SMSI)by diverse methodologies has emerged as one of the promising approaches to fabricating robust supported metal catalysts.In this study,we report an L-ascorbic acid(AA)-inducing strategy to generate SMSI on a titania-supported gold(Au)catalyst after high-temperature treatment in an inert atmosphere(600℃,N_(2)).The AA-induced SMSI can efficiently stabilize Au nanoparticles(NPs)and preserve their catalytic performance.The detailed study reveals that the key to realizing this SMSI is the generation of oxygen vacancies within the TiO_(2) support induced by the adsorbed AA,which drives the formation of the Ti Oxpermeable layer onto the Au NPs.The strategy could be extended to TiO_(2)-supported Au catalysts with different crystal phases and platinum group metals,such as Pt,Pd,and Rh.This work offers a promising novel route to design stable and efficient supported noble metal catalysts by constructing SMSI using simple reducing organic adsorbent.
