During thewater treatment process,chlorination and ultraviolet(UV)sterilization can modify microplastics(MPs)and alter their physicochemical properties,causing various changes between MPs and other pollutants.In this ...During thewater treatment process,chlorination and ultraviolet(UV)sterilization can modify microplastics(MPs)and alter their physicochemical properties,causing various changes between MPs and other pollutants.In this study,the impact of chlorination and UV modification on the physicochemical properties of polystyrene(PS)and polyvinyl chloride(PVC)were investigated,and the adsorption behavior of pefloxacin(PEF)before and after modificationwas examined.The effect of pH,ionic strength,dissolved organicmatter,heavymetal ions and other water environmental conditions on adsorption behavior was revealed.The results showed that PS had a higher adsorption capacity of PEF than PVC,and the modification increased the presence of O-containing functional groups in the MPs,thereby enhancing the adsorption capacity of both materials.Chlorination had a more significant impact on the physicochemical properties of MPs compared to UV irradiation within the same time period,leading to better adsorption performance of chlorination.The optimal pH for adsorption was found to be 6,and NaCl,sodium alginate and Cu2+would inhibit adsorption to varying degrees,among which the inhibition caused by pH was the strongest.Chlorination and UV modification would weaken the inhibitory effect of environmental factors on the adsorption of PEF by MPs.The main mechanisms of adsorption involved electrostatic interaction and hydrogen bonding.The study clarified the effects of modification on the physicochemical properties of MPs,providing reference for subsequent biotoxicity analysis and environmental protection studies.展开更多
The mass production and widespread use of Pharmaceuticals and Personal Care Products(PPCPs)have posed a serious threat to the water environment and public health.In this work,a green metal-based Metal Organic Framewor...The mass production and widespread use of Pharmaceuticals and Personal Care Products(PPCPs)have posed a serious threat to the water environment and public health.In this work,a green metal-based Metal Organic Framework(MOF)Bi-NH_(2)-BDC was prepared and characterized,and the adsorption characteristics of Bi-NH_(2)-BDCwere investigated with typical PPCPs-diclofenac sodium(DCF).It was found that DCF mainly covered the adsorbent surface as a single molecular layer,the adsorption reaction was a spontaneous,entropyincreasing exothermic process and the adsorption mechanisms between Bi-NH_(2)-BDC and DCF were hydrogen bonding,π-πinteractions and electrostatic interactions.In addition,Bi-NH_(2)-BDC also had considerable photocatalytic properties,and its application in adsor-bent desorption treatment effectively solved the problem of secondary pollution,achieving a green and sustainable adsorption desorption cycle.展开更多
This study investigates the adsorption mechanism,the film formation process,and the inhibition performance of benzotriazole(BTAH)on carbon steels with different grain sizes(i.e.,24.5,4.3,and 0.6μm)in 3.5 wt.%NaCl sol...This study investigates the adsorption mechanism,the film formation process,and the inhibition performance of benzotriazole(BTAH)on carbon steels with different grain sizes(i.e.,24.5,4.3,and 0.6μm)in 3.5 wt.%NaCl solution.The results demonstrate that grain refinement significantly impacts the adsorption and inhibition performance of BTAH on carbon steels.Ultra-refinement of steel grains to 0.6μm improves the maximum inhibition efficiency of BTAH to 90.0%within 168 h of immersion,which was much higher than that of the steels with 24.5μm(73.6%)and 4.3μm grain sizes(81.7%).Notably,grain sizes of 4.3 and 0.6μm facilitate a combination of physisorption and chemisorption of BTAH after 120 h of immersion,as evidenced by the X-ray photoelectron spectroscopy(XPS)results and Langmuir adsorption isotherms,while BTAH adsorbed on carbon steels with a grain size of 24.5μm through physisorption during the 168 h of immersion.Ultra-refinement of grains has beneficial impacts on promoting the formation of a stable and dense corrosion inhibitor film,leading to improved corrosion resistance and the mitigation of non-uniform corrosion.These advantageous effects can be attributed to the higher adsorption energy at grain boundaries(approximately-3.12 eV)compared to grain interiors(ranging from-0.79 to 2.47 eV),promoting both the physisorption and chemisorption of organic corrosion inhibitors.The investigation comprehensively illustrates,for the first time,the effects of grain size on the adsorption mechanism,film formation process,and inhibition performance of organic corrosion inhibitors on carbon steels.This study demonstrates a promising approach to enhancing corrosion inhibition performance through microstructural design.展开更多
Current research on heterogeneous advanced oxidation processes(HAOPs)predominantly emphasizes catalyst iteration and innovation.Significant efforts have been made to regulate the electron structure and optimize the el...Current research on heterogeneous advanced oxidation processes(HAOPs)predominantly emphasizes catalyst iteration and innovation.Significant efforts have been made to regulate the electron structure and optimize the electron distribution,thereby increasing the catalytic activity.However,this focus often overshadows an equally essential aspect of HAOPs:the adsorption effect.Adsorption is a critical initiator for triggering the interaction of oxidants and contaminants with heterogeneous catalysts.The efficacy of these interactions is influenced by a variety of physicochemical properties,including surface chemistry and pore sizes,which determine the affinities between contaminants and material surfaces.This dispar ity in affinity is pivotal because it underpins the selective removal of contaminants,especially in complex waste streams containing diverse contaminants and competing matrices.Consequently,understanding and mastering these interfacial interactions is fundamentally indispensable not only for improving pro cess efficiency but also for enhancing the selectivity of contaminant removal.Herein,we highlight the importance of adsorption-driven interfacial interactions for fundamentally elucidating the catalytic mechanisms of HAOPs.Such interactions dictate the overall performance of the treatment processes by balancing the adsorption,reaction,and desorption rates on the catalyst surfaces.Elucidating the adsorption effect not only shifts the paradigm in understanding HAOPs but also improves their practical ity in water treatment and wastewater decontamination.Overall,we propose that revisiting adsorption driven interfacial interactions holds great promise for optimizing catalytic processes to develop effective HAOP strategies.展开更多
Recycling rare earth elements(REEs)from waste is necessary for an environmentally sustainable reuse and wastewater management approach.Na-A zeolite was synthesized from coal fly ash(CFA)and applied for Ce^(3+)adsorpti...Recycling rare earth elements(REEs)from waste is necessary for an environmentally sustainable reuse and wastewater management approach.Na-A zeolite was synthesized from coal fly ash(CFA)and applied for Ce^(3+)adsorption.Fourier transform infrared(FTIR)spectra show peaks at 790,500 and 467 cm^(-1),which are bond vibrations of Si-O-Si,Si with Al-O and Si-O-.The surface area is 15.88 m^(2)/g,with a pore size of 2.14 nm.SEM images show a cubic shape,which indicates the formation of zeolite.Field emission and energy disperse spectroscopy(EDS)shows the formation of Si,Al,Na,and O.Na-A zeolite was applied for Ce^(3+)adsorption.The optimum conditions for Ce^(3+)adsorption are 50 ppm concentration,360 min,and pH 6.The maximum adsorption capacity is 176.49 mg/g.Based on the results,it is found that the adsorption of Ce^(3+)by Na-A zeolite is pseudo-second-order.The desorption test using HNO_(3) is more effective than using HCl and H_(2)SO_(4).A desorption efficiency of 97.22%is obtained at 4 cycles.Adsorption test using real sample wastewater demonstrates an adsorption efficiency of 83.35%.展开更多
In order to reveal the effect of 2-hydroxy-3-naphthyl hydroxamic acid(H205)on the flotation behavior and action mechanism of bastnaesite,single-mineral flotation experiments of bastnaesite were conducted.The flotation...In order to reveal the effect of 2-hydroxy-3-naphthyl hydroxamic acid(H205)on the flotation behavior and action mechanism of bastnaesite,single-mineral flotation experiments of bastnaesite were conducted.The flotation recovery of bastnaesites can be achieved more than 90%when the aeration rate is 40 mL/min,the rotational speed is 200 r/min,the H205 dosage is 120 mg/L,and the pulp pH ranges from 7 to 9.The action mechanism of H205 on the surface of bastnaesite was studied by simultaneous thermogravimetry and differential scanning calorimetry(TG-DSC),Zeta potential measurements,Fourier transform-infrared spectra(FT-IR)and X-ray photoelectron spectroscopy(XPS).These analysis results show that under suitable flotation conditions,H205 has an obvious adsorption phenomenon on the surface of bastnaesite.The adsorption involves electrostatic interactions and chemical interactions,namely H205 has a strong collecting ability of bastnaesite due to the synergism of electrostatic adsorption and chemical adsorption.This study systematically reveals the flotation behavior and adsorption mechanism of H205 on the surface of bastnaesite,and provides useful theoretical guidance for efficient flotation separation of bastnaesite.展开更多
Adsorption by solid amine adsorbent is a promising technology for decarbonization of flue gas.However,adsorption properties of many solid amine adsorbents need to be enhanced,and it is necessary to further study the C...Adsorption by solid amine adsorbent is a promising technology for decarbonization of flue gas.However,adsorption properties of many solid amine adsorbents need to be enhanced,and it is necessary to further study the CO_(2)adsorption mechanism.A novel CO_(2)adsorbent with high capacity was obtained by grafting 3-aminopropyltriethoxysilane(APTES)on a micro-mesoporous composite molecular sieve ZSM-5/MCM-48 as the support,and then impregnated with tetraethylenepentamine(TEPA)or polyethyleneimine(PEI).The maximum adsorption capacity of APTES-ZSM-5/MCM-48-TEPA-60(A-ZM-T60),loaded with 60%(in mass)TEPA,for CO_(2)reaches 5.82 mmol·g^(-1) at 60℃in 15%(in volume)CO_(2).Carbamate,alkyl ammonium carbamate and carbonate are generated during the chemical adsorption,which is dominant for CO_(2)adsorption because of the reaction between CO_(2)and amino groups on the adsorbent,simultaneously accompanied by weak physical adsorption.All above data confirm that these composites display an outstanding adsorption performance with a bright future for CO_(2)capture from flue gas after desulfurization.展开更多
Hydroxyapatite nanoparticles(HAP NPs)were synthesized by a one‐step hydrothermal method.The surface of HAP NPs was grafted-SH and-COOH chelating groups via in situ surface‐modification with iminodiacetic acid(IDA)an...Hydroxyapatite nanoparticles(HAP NPs)were synthesized by a one‐step hydrothermal method.The surface of HAP NPs was grafted-SH and-COOH chelating groups via in situ surface‐modification with iminodiacetic acid(IDA)and 3‐mercaptopropyl trimethoxysilane(MPS)to afford dual surface‐capped nano‐amendment HAPIDA/MPS.The structure of HAP‐IDA/MPS was characterized,and its adsorption performance for Hg^(2+),Cu^(2+),Zn^(2+),Ni^(2+),Co^(2+),and Cd^(2+)was evaluated.The total adsorption capacity of 0.10 g HAP‐IDA/MPS nano‐amendment for Hg^(2+),Cu^(2+),Zn^(2+),Ni^(2+),Co^(2+),and Cd^(2+)with an initial mass concentration of 20 mg·L^(-1) reached 13.7 mg·g^(-1),about 4.3 times as much as that of HAP.Notably,HAP‐IDA/MPS nano‐amendment displayed the highest immobilization rate for Hg^(2+),possibly because of its chemical reaction with-SH to form sulfide,possessing the lowest solubility product constant among a variety of metal sulfides.展开更多
The removal of arsenic from water is essential for the protection of public health. To investigate the adsorption capabilities of laterite, sandstone, and shale for the removal of arsenic from aqueous solutions, colum...The removal of arsenic from water is essential for the protection of public health. To investigate the adsorption capabilities of laterite, sandstone, and shale for the removal of arsenic from aqueous solutions, column experiments were conducted. In this study, raw materials and heat-treated (calcined) materials were examined. The experiments assessed the influence of various parameters, including initial concentration, bed depth, and the effects of heat treatment. The findings revealed that the breakthrough curves were influenced by the initial concentration of arsenic, the depth of the bed, and the type of material used. For an initial arsenic concentration of 5 mg/L, columns containing 85 cm of calcined laterite, sandstone, and shale produced volumes of 7460 ml (1492 min), 3510 ml (702 min), and 4400 ml (880 min) of water with arsenic levels below 0.01 mg/L, respectively. These calcined materials demonstrate significant potential for the effective removal of arsenic from water.展开更多
Adsorption as an effective technique for the remediation of wastewater has been widely used in industrial wastewater treatment due to the advantage of cost-effectiveness,availability of the adsorbent and ease of opera...Adsorption as an effective technique for the remediation of wastewater has been widely used in industrial wastewater treatment due to the advantage of cost-effectiveness,availability of the adsorbent and ease of operation.However,the low adsorption capacity of the reported adsorbents is still a challenge for wastewater treatment with highefficiency.Here,we developed a super adsorbent(SUA-1),which was a kind of porous carbon nanofibers derived from a composite of PAN-based electrospinning and ZIF-8(PAN/ZIF-8)via simple heat treatment process.The asprepared SUA showed an ultra-high adsorption capacity for adsorbing methyl blue(MB)at nearly three times its own weight,as high as 2998.18 mg/g.A series tests demonstrated that the pore-making effect of ZIF-8 during heat treatment process endowed high BET surface area and generated ZnO components as chemical adsorption center.Under the synergistic effect of bonding and non-bonding forces including ionic bond,electrostatic interaction,andπ-πinteraction,the adsorption capacity has been greatly improved.In view of promising efficiency,this work provides guidance and insights for the preparation of highly efficient adsorbents based on electrospinning derived porous carbon nanofibers.展开更多
Since the discovery of carbon dots(CDs)in 2004,the unique photoluminescence phenomenon of CDs has attracted widespread attention.However,the molecular weight of CDs has not been adequately quantified at present,due to...Since the discovery of carbon dots(CDs)in 2004,the unique photoluminescence phenomenon of CDs has attracted widespread attention.However,the molecular weight of CDs has not been adequately quantified at present,due to CDs are atomically imprecise and their molecular weight distribution is broad.In this paper,a series of Pluronic-modified CDs were prepared and the structure of the CDs was briefly analyzed.Subsequently,a molecular weight measurement method based on colligative properties was developed,and the correction coefficient in the algorithm was briefly analyzed.The calculated molecular weight was applied to the determination of surface adsorption capacity.This work provided a method for averaging the molecular weight of atomically imprecise particulate materials,which is expected to provide new opportunities in related fields.展开更多
ZrCoRE(RE denotes rare earth elements)non-evaporable getter films have significant applications in vacuum packaging of micro-electro mechanical system devices because of their excellent gas adsorption performance,low ...ZrCoRE(RE denotes rare earth elements)non-evaporable getter films have significant applications in vacuum packaging of micro-electro mechanical system devices because of their excellent gas adsorption performance,low activation temperature and environmental friendliness.The films were deposited using DC magnetron sputtering with argon and krypton gases under various deposition pressures.The effects of sputtering gas type and pressure on the morphology and hydrogen adsorption performance of ZrCoRE films were investigated.Results show that the films prepared in Ar exhibit a relatively dense structure with fewer grain boundaries.The increase in Ar pressure results in more grain boundaries and gap structures in the films.In contrast,films deposited in Kr display a higher density of grain boundaries and cluster structures,and the films have an obvious columnar crystal structure,with numerous interfaces and gaps distributed between the columnar structures,providing more paths for gas diffusion.As Kr pressure increases,the film demonstrates more pronounced continuous columnar structure growth,accompanied by deeper and wider grain boundaries.This structural configuration provides a larger specific surface area,which significantly improves the hydrogen adsorption speed and capacity.Consequently,high Ar and Kr pressures are beneficial to improve the adsorption performance.展开更多
Treatment of precious metals in electronic waste has attracted tremendous attention and is essential for both environmental protection and resource sustainable development.In this study,a novel adsorbent for precious ...Treatment of precious metals in electronic waste has attracted tremendous attention and is essential for both environmental protection and resource sustainable development.In this study,a novel adsorbent for precious metal ions,V_(2)O_(3)spiny hollow nanospheres(pV_(2)O_(3)SHN),was synthe sized through a one-step hydrothermal-as sis ted methodology for the adsorption of Au(Ⅲ),Ag(Ⅰ),Pd(Ⅱ),and Pt(Ⅳ) from the leaching solution of electronic waste.The results reveal that the p-V2O3SHN hierarchy was successfully constructed with a hollow structure and dense spiny morphology.The prepared p-V2O3SHN can effectively remove precious metal ions such as Au(Ⅲ),Ag(Ⅰ),Pd(Ⅱ),and Pt(Ⅳ),with the selective capture order being Au(Ⅲ)> Ag(Ⅰ)> Pt(Ⅳ)> Pd(Ⅱ)> other metal ions.This superior adsorption capability can be attributed to the multi-diffusible,intermingled composition,and numerous active sites decorating the p-V2O3SHN hierarchy,facilitating the uptake of Au(Ⅲ),Ag(Ⅰ),Pd(Ⅱ),and Pt(Ⅳ) ions from electronic waste.The Langmuir model provided a better fit for the uptake process,revealing maximum uptake capacities of 833.33 mg/g for Au(Ⅲ),370.37 mg/g for Ag(Ⅰ),42.01 mg/g for Pd(Ⅱ),and 77.51 mg/g for Pt(Ⅳ) on p-V_(2)O_(3)SHN.Remarkably,p-V_(2)O_(3)SHN exhibited a robust affinity for the adsorbate due to the presence of surface defects and reduction reactions.The new p-V2O3SHN also demonstrated good reusability for three sorption cycles,highlighting its potential for electronic waste treatment.Due to its facile synthesis and excellent efficiency,hierarchical p-V2O3SHN presents itself as a promising candidate for the selective uptake of Au(Ⅲ),Ag(Ⅰ),Pt(Ⅳ),and Pd(Ⅱ) from electronic waste.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
Increasing attention has been paid to radioactive wastewater to direct discharge in Japan or accidental leaks.Strontium-90(90Sr)and Cobalt-60(^(60)Co)are the most hazardous nuclides in waste discharged form nuclear re...Increasing attention has been paid to radioactive wastewater to direct discharge in Japan or accidental leaks.Strontium-90(90Sr)and Cobalt-60(^(60)Co)are the most hazardous nuclides in waste discharged form nuclear reactors.Because of their high solubility and long half-lives,these radioisotopes can persist for hundreds of years before decaying to negligible levels.Herein,a green and biodegradable material nanoscale zero-valent iron(nZVI)supported by bacterial cellulose particles(BCP-nZVI)is constructed for the first time to adsorb Co^(2+)and Sr^(2+)in single and binary systems.BCP-nZVI shows superior adsorption capacities of Co^(2+)and Sr^(2+)in a single system within a wide range of pH values from 5 to 7,while the coexistence of Co^(2+)adsorption inhibits the Sr^(2+)in binary system.Pseudo-second-order dynamics model and Langmuir isothermal model can be indicated the BCP-nZVI adsorption progress with 107.10 mg/g(Co^(2+))and 64.96 mg/g(Sr^(2+))maximum adsorption capacity.BCP-nZVI has outstanding stability,allowing it to be stored for more than one month with compromising its performance.More importantly,BCP-nZVI exhibits exceptional removal efficiency of Co^(2+)(92.53%)and Sr^(2+)(58.62%)removal in natural seawater systems.The mechanism investigation illustrates the high adsorption capacity of BCP-nZVI for Co^(2+)is controlled by redox and hydroxyl complexation.While Sr^(2+)is controlled by hydroxyl complexed adsorption,thus it has weak against interference by cations like Na^(+),Ca^(2+),etc.BCP-nZVI exhibits the advantages of high adsorption capacity,wide pH range,strong stability,and good applicability in natural seawater,which has excellent potential for application in radioactive ions removal.展开更多
A new adsorbent was successfully prepared by hydrothermal treatment and chemical activation through coal gasification fine slag(CGFS)and blue algae(BA)as raw materials and used for CO_(2)capture.The CO_(2)chemisorptio...A new adsorbent was successfully prepared by hydrothermal treatment and chemical activation through coal gasification fine slag(CGFS)and blue algae(BA)as raw materials and used for CO_(2)capture.The CO_(2)chemisorption capacity of the adsorbent was further enhanced by taking advantage of the nitrogenous bases contained in the BA.In the hydrothermal process,the addition of BA significantly increased the content of pyrrole nitrogen in the adsorbent.In the activation process,pyrrole nitrogen gradually changed into pyridine nitrogen and graphite nitrogen.Increased BA addition result in a higher specific surface area and microporosity of the adsorbent.The CO_(2)adsorption performance test proved that the CGFS-50%-CA sample has the strongest CO_(2)adsorption capacity at low temperature,up to 15.59 cm^(3)/g,which is mainly through physical adsorption,and the CGFS-10%-CA sample has the strongest CO_(2)adsorption capacity at high temperature,up to 7.31 cm^(3)/g,which is mainly through chemical adsorption.CO_(2)uptake of the CGFS-10%-CA sample was well maintained after 10 cycles,with regeneration efficiencies above 99%.The results indicate that the novel adsorbents with coexistence of physical and chemical adsorption have great potential for CO_(2)adsorption applications.展开更多
This study mainly investigates the influence of pore water characteristics on the adsorption properties of coalbed methane through integrated low field nuclear magnetic resonance(LF-NMR),adsorption experiments,and mol...This study mainly investigates the influence of pore water characteristics on the adsorption properties of coalbed methane through integrated low field nuclear magnetic resonance(LF-NMR),adsorption experiments,and molecular dynamics(MD)simulations.Pore water states in three coal ranks were characterized during progressive hydration.Multi-scale analysis revealed how pore water evolution regulates methane adsorption processes.During the diffusion-dominated stage(M2-M3),adsorbed water penetrates into the micropores.In the highly wettable brown coal(L1),the adsorbed water content reaches 2.12 g while in the anthracite(A1),it is only 0.29 g.During the active water injection stage(M4-M6),non-adsorbed water dominates in anthracite(over 85%of the total water content of 4.01 g),while adsorbed water remains dominant in lignite(over 60%of the total water content of 3.52 g).Water content plays a key role in methane adsorption in coal.During the water addition phase,the influence of methane adsorption on medium-to-low-rank coal is relatively weak,while the methane adsorption capacity of high-rank coal A1 shows a significant decrease during both the water diffusion and water addition phases,corresponding to a reduction in Langmuir volume of 21.22 cm^(3)/g.Molecular dynamics(MD)results further show that the free energy between molecules on the surface of hydroxyl-modified coal increases,with hydroxyl groups driving electrostatic interactions between coal and water molecules.Increased steric hindrance inhibits hydrogen bond formation and reduces the rate of hydrogen bond growth.There is a significant correlation between pore water content and coal-water molecular interaction energy,which cross-scale validates the results of LF-NMR testing and MD simulations.展开更多
An in-depth understanding of the competition mechanism between olefins and different types of sulfides in gasoline is essential to improve the desulfurization selectivity of the adsorption desulfurization process(ADS)...An in-depth understanding of the competition mechanism between olefins and different types of sulfides in gasoline is essential to improve the desulfurization selectivity of the adsorption desulfurization process(ADS).In this study,the competitive adsorption and diffusion mechanism of two systems,diethyl sulfide/cyclohexene and n-butyl mercaptan/cyclohexene,with different adsorption amounts in siliceous faujasite zeolite(FAU) were investigated by Monte Carlo(MC) and molecular dynamics(MD).The systems exhibited a two-stage loading-dependent competitive adsorption and diffusion mechanism,with an inflection point of 32 molecule/UC(moleculers per microcoulomb).Before the inflection point(4-32molecule/UC),the competition mechanism of the two systems was the "optimal-displacement" mechanism.After the inflection point,the mechanism of the diethyl sulfide/cyclohexene changed to "relocation-displacement",while that of the n-butyl mercaptan/cyclohexene system changed to "dominantdisplacement".Compared to ether functional groups,the alcohol functional group has higher polarity and stronger adsorption stability,thus occupying more favorable adsorption sites within the supercages(SCs),while ethyl sulfide shifts outward to other sites within other SCs.In addition,the diffusion performance of adsorbent is related to the adsorption energy.The lower the adsorption energy,the weaker the diffusion ability.Meanwhile,the diffusion performance of adsorbates is better at high temperatures and low adsorption capacity.The effect of temperatu re on the desulfu rization selectivity was determined.A lower temperature is favorable for the adsorption capacity of the two systems and the removal selectivity of sulfides.This study provides fundamental insights into the competitive adsorption and diffusion mechanisms among sulfides,mercaptans and olefins,offering theoretical guidance for adsorbent design and reaction temperature optimization.展开更多
基金supported by the Shanxi Scholarship Council of China(No.2023-054)the Applied Basic Research Project of Shanxi Province,China(No.20210302123121)the National Natural Science Foundation of China(No.52170045).
文摘During thewater treatment process,chlorination and ultraviolet(UV)sterilization can modify microplastics(MPs)and alter their physicochemical properties,causing various changes between MPs and other pollutants.In this study,the impact of chlorination and UV modification on the physicochemical properties of polystyrene(PS)and polyvinyl chloride(PVC)were investigated,and the adsorption behavior of pefloxacin(PEF)before and after modificationwas examined.The effect of pH,ionic strength,dissolved organicmatter,heavymetal ions and other water environmental conditions on adsorption behavior was revealed.The results showed that PS had a higher adsorption capacity of PEF than PVC,and the modification increased the presence of O-containing functional groups in the MPs,thereby enhancing the adsorption capacity of both materials.Chlorination had a more significant impact on the physicochemical properties of MPs compared to UV irradiation within the same time period,leading to better adsorption performance of chlorination.The optimal pH for adsorption was found to be 6,and NaCl,sodium alginate and Cu2+would inhibit adsorption to varying degrees,among which the inhibition caused by pH was the strongest.Chlorination and UV modification would weaken the inhibitory effect of environmental factors on the adsorption of PEF by MPs.The main mechanisms of adsorption involved electrostatic interaction and hydrogen bonding.The study clarified the effects of modification on the physicochemical properties of MPs,providing reference for subsequent biotoxicity analysis and environmental protection studies.
基金supported by Liaoning Revitalization Talents Program(No.XLYC1907173)the Science and Technology General Project of Liaoning Provincial Education Department(No.LJKMZ20221835)the National Natural Science Foundation of China(Nos.22006073 and 22205027).
文摘The mass production and widespread use of Pharmaceuticals and Personal Care Products(PPCPs)have posed a serious threat to the water environment and public health.In this work,a green metal-based Metal Organic Framework(MOF)Bi-NH_(2)-BDC was prepared and characterized,and the adsorption characteristics of Bi-NH_(2)-BDCwere investigated with typical PPCPs-diclofenac sodium(DCF).It was found that DCF mainly covered the adsorbent surface as a single molecular layer,the adsorption reaction was a spontaneous,entropyincreasing exothermic process and the adsorption mechanisms between Bi-NH_(2)-BDC and DCF were hydrogen bonding,π-πinteractions and electrostatic interactions.In addition,Bi-NH_(2)-BDC also had considerable photocatalytic properties,and its application in adsor-bent desorption treatment effectively solved the problem of secondary pollution,achieving a green and sustainable adsorption desorption cycle.
基金support of the National Natural Science Foundation of China(Nos.52171063,52274362,and 52371049)the Key R&D projects of Henan Province(No.221111230800)+1 种基金the Doctoral Fund of Henan University of Technology(No.2023BS047)the Natural science Project of Zhengzhou Science and Technology Bureau(No.22ZZRDZX04)。
文摘This study investigates the adsorption mechanism,the film formation process,and the inhibition performance of benzotriazole(BTAH)on carbon steels with different grain sizes(i.e.,24.5,4.3,and 0.6μm)in 3.5 wt.%NaCl solution.The results demonstrate that grain refinement significantly impacts the adsorption and inhibition performance of BTAH on carbon steels.Ultra-refinement of steel grains to 0.6μm improves the maximum inhibition efficiency of BTAH to 90.0%within 168 h of immersion,which was much higher than that of the steels with 24.5μm(73.6%)and 4.3μm grain sizes(81.7%).Notably,grain sizes of 4.3 and 0.6μm facilitate a combination of physisorption and chemisorption of BTAH after 120 h of immersion,as evidenced by the X-ray photoelectron spectroscopy(XPS)results and Langmuir adsorption isotherms,while BTAH adsorbed on carbon steels with a grain size of 24.5μm through physisorption during the 168 h of immersion.Ultra-refinement of grains has beneficial impacts on promoting the formation of a stable and dense corrosion inhibitor film,leading to improved corrosion resistance and the mitigation of non-uniform corrosion.These advantageous effects can be attributed to the higher adsorption energy at grain boundaries(approximately-3.12 eV)compared to grain interiors(ranging from-0.79 to 2.47 eV),promoting both the physisorption and chemisorption of organic corrosion inhibitors.The investigation comprehensively illustrates,for the first time,the effects of grain size on the adsorption mechanism,film formation process,and inhibition performance of organic corrosion inhibitors on carbon steels.This study demonstrates a promising approach to enhancing corrosion inhibition performance through microstructural design.
基金supported by the National Key Research and Development Program of China(2022YFC3205300)the National Natural Science Foundation of China(22176124).
文摘Current research on heterogeneous advanced oxidation processes(HAOPs)predominantly emphasizes catalyst iteration and innovation.Significant efforts have been made to regulate the electron structure and optimize the electron distribution,thereby increasing the catalytic activity.However,this focus often overshadows an equally essential aspect of HAOPs:the adsorption effect.Adsorption is a critical initiator for triggering the interaction of oxidants and contaminants with heterogeneous catalysts.The efficacy of these interactions is influenced by a variety of physicochemical properties,including surface chemistry and pore sizes,which determine the affinities between contaminants and material surfaces.This dispar ity in affinity is pivotal because it underpins the selective removal of contaminants,especially in complex waste streams containing diverse contaminants and competing matrices.Consequently,understanding and mastering these interfacial interactions is fundamentally indispensable not only for improving pro cess efficiency but also for enhancing the selectivity of contaminant removal.Herein,we highlight the importance of adsorption-driven interfacial interactions for fundamentally elucidating the catalytic mechanisms of HAOPs.Such interactions dictate the overall performance of the treatment processes by balancing the adsorption,reaction,and desorption rates on the catalyst surfaces.Elucidating the adsorption effect not only shifts the paradigm in understanding HAOPs but also improves their practical ity in water treatment and wastewater decontamination.Overall,we propose that revisiting adsorption driven interfacial interactions holds great promise for optimizing catalytic processes to develop effective HAOP strategies.
基金Project supported by Rumah Program 2023 and Net Zero Emission Program(1507/Ⅱ.7/HK.01.00/6/2023)a research facility from the National Research and Innovation Agency of Republic of Indonesia。
文摘Recycling rare earth elements(REEs)from waste is necessary for an environmentally sustainable reuse and wastewater management approach.Na-A zeolite was synthesized from coal fly ash(CFA)and applied for Ce^(3+)adsorption.Fourier transform infrared(FTIR)spectra show peaks at 790,500 and 467 cm^(-1),which are bond vibrations of Si-O-Si,Si with Al-O and Si-O-.The surface area is 15.88 m^(2)/g,with a pore size of 2.14 nm.SEM images show a cubic shape,which indicates the formation of zeolite.Field emission and energy disperse spectroscopy(EDS)shows the formation of Si,Al,Na,and O.Na-A zeolite was applied for Ce^(3+)adsorption.The optimum conditions for Ce^(3+)adsorption are 50 ppm concentration,360 min,and pH 6.The maximum adsorption capacity is 176.49 mg/g.Based on the results,it is found that the adsorption of Ce^(3+)by Na-A zeolite is pseudo-second-order.The desorption test using HNO_(3) is more effective than using HCl and H_(2)SO_(4).A desorption efficiency of 97.22%is obtained at 4 cycles.Adsorption test using real sample wastewater demonstrates an adsorption efficiency of 83.35%.
基金Project supported by the Natural Science Foundation Innovation Group Project of Hubei Province(2023AFA044)the National Natural Science Foundation of China(52222405)+1 种基金the Science and Technology Research Project of Education Department of Hubei Province(Q20221505)the China Postdoctoral Science(2023M731041)。
文摘In order to reveal the effect of 2-hydroxy-3-naphthyl hydroxamic acid(H205)on the flotation behavior and action mechanism of bastnaesite,single-mineral flotation experiments of bastnaesite were conducted.The flotation recovery of bastnaesites can be achieved more than 90%when the aeration rate is 40 mL/min,the rotational speed is 200 r/min,the H205 dosage is 120 mg/L,and the pulp pH ranges from 7 to 9.The action mechanism of H205 on the surface of bastnaesite was studied by simultaneous thermogravimetry and differential scanning calorimetry(TG-DSC),Zeta potential measurements,Fourier transform-infrared spectra(FT-IR)and X-ray photoelectron spectroscopy(XPS).These analysis results show that under suitable flotation conditions,H205 has an obvious adsorption phenomenon on the surface of bastnaesite.The adsorption involves electrostatic interactions and chemical interactions,namely H205 has a strong collecting ability of bastnaesite due to the synergism of electrostatic adsorption and chemical adsorption.This study systematically reveals the flotation behavior and adsorption mechanism of H205 on the surface of bastnaesite,and provides useful theoretical guidance for efficient flotation separation of bastnaesite.
基金National Natural Science Foundation of China(51966002)Natural Science Foundation of Guangxi Province(2020GXNSFAA159144)。
文摘Adsorption by solid amine adsorbent is a promising technology for decarbonization of flue gas.However,adsorption properties of many solid amine adsorbents need to be enhanced,and it is necessary to further study the CO_(2)adsorption mechanism.A novel CO_(2)adsorbent with high capacity was obtained by grafting 3-aminopropyltriethoxysilane(APTES)on a micro-mesoporous composite molecular sieve ZSM-5/MCM-48 as the support,and then impregnated with tetraethylenepentamine(TEPA)or polyethyleneimine(PEI).The maximum adsorption capacity of APTES-ZSM-5/MCM-48-TEPA-60(A-ZM-T60),loaded with 60%(in mass)TEPA,for CO_(2)reaches 5.82 mmol·g^(-1) at 60℃in 15%(in volume)CO_(2).Carbamate,alkyl ammonium carbamate and carbonate are generated during the chemical adsorption,which is dominant for CO_(2)adsorption because of the reaction between CO_(2)and amino groups on the adsorbent,simultaneously accompanied by weak physical adsorption.All above data confirm that these composites display an outstanding adsorption performance with a bright future for CO_(2)capture from flue gas after desulfurization.
文摘Hydroxyapatite nanoparticles(HAP NPs)were synthesized by a one‐step hydrothermal method.The surface of HAP NPs was grafted-SH and-COOH chelating groups via in situ surface‐modification with iminodiacetic acid(IDA)and 3‐mercaptopropyl trimethoxysilane(MPS)to afford dual surface‐capped nano‐amendment HAPIDA/MPS.The structure of HAP‐IDA/MPS was characterized,and its adsorption performance for Hg^(2+),Cu^(2+),Zn^(2+),Ni^(2+),Co^(2+),and Cd^(2+)was evaluated.The total adsorption capacity of 0.10 g HAP‐IDA/MPS nano‐amendment for Hg^(2+),Cu^(2+),Zn^(2+),Ni^(2+),Co^(2+),and Cd^(2+)with an initial mass concentration of 20 mg·L^(-1) reached 13.7 mg·g^(-1),about 4.3 times as much as that of HAP.Notably,HAP‐IDA/MPS nano‐amendment displayed the highest immobilization rate for Hg^(2+),possibly because of its chemical reaction with-SH to form sulfide,possessing the lowest solubility product constant among a variety of metal sulfides.
文摘The removal of arsenic from water is essential for the protection of public health. To investigate the adsorption capabilities of laterite, sandstone, and shale for the removal of arsenic from aqueous solutions, column experiments were conducted. In this study, raw materials and heat-treated (calcined) materials were examined. The experiments assessed the influence of various parameters, including initial concentration, bed depth, and the effects of heat treatment. The findings revealed that the breakthrough curves were influenced by the initial concentration of arsenic, the depth of the bed, and the type of material used. For an initial arsenic concentration of 5 mg/L, columns containing 85 cm of calcined laterite, sandstone, and shale produced volumes of 7460 ml (1492 min), 3510 ml (702 min), and 4400 ml (880 min) of water with arsenic levels below 0.01 mg/L, respectively. These calcined materials demonstrate significant potential for the effective removal of arsenic from water.
基金Natural Science Foundation of China(22134005,22204011)Chongqing Talents Program for Outstanding Scientists(cstc2021ycjh-bgzxm0179)。
文摘Adsorption as an effective technique for the remediation of wastewater has been widely used in industrial wastewater treatment due to the advantage of cost-effectiveness,availability of the adsorbent and ease of operation.However,the low adsorption capacity of the reported adsorbents is still a challenge for wastewater treatment with highefficiency.Here,we developed a super adsorbent(SUA-1),which was a kind of porous carbon nanofibers derived from a composite of PAN-based electrospinning and ZIF-8(PAN/ZIF-8)via simple heat treatment process.The asprepared SUA showed an ultra-high adsorption capacity for adsorbing methyl blue(MB)at nearly three times its own weight,as high as 2998.18 mg/g.A series tests demonstrated that the pore-making effect of ZIF-8 during heat treatment process endowed high BET surface area and generated ZnO components as chemical adsorption center.Under the synergistic effect of bonding and non-bonding forces including ionic bond,electrostatic interaction,andπ-πinteraction,the adsorption capacity has been greatly improved.In view of promising efficiency,this work provides guidance and insights for the preparation of highly efficient adsorbents based on electrospinning derived porous carbon nanofibers.
文摘Since the discovery of carbon dots(CDs)in 2004,the unique photoluminescence phenomenon of CDs has attracted widespread attention.However,the molecular weight of CDs has not been adequately quantified at present,due to CDs are atomically imprecise and their molecular weight distribution is broad.In this paper,a series of Pluronic-modified CDs were prepared and the structure of the CDs was briefly analyzed.Subsequently,a molecular weight measurement method based on colligative properties was developed,and the correction coefficient in the algorithm was briefly analyzed.The calculated molecular weight was applied to the determination of surface adsorption capacity.This work provided a method for averaging the molecular weight of atomically imprecise particulate materials,which is expected to provide new opportunities in related fields.
基金National Natural Science Foundation of China(62171208)Natural Science Foundation of Gansu Province(23JRRA1355)。
文摘ZrCoRE(RE denotes rare earth elements)non-evaporable getter films have significant applications in vacuum packaging of micro-electro mechanical system devices because of their excellent gas adsorption performance,low activation temperature and environmental friendliness.The films were deposited using DC magnetron sputtering with argon and krypton gases under various deposition pressures.The effects of sputtering gas type and pressure on the morphology and hydrogen adsorption performance of ZrCoRE films were investigated.Results show that the films prepared in Ar exhibit a relatively dense structure with fewer grain boundaries.The increase in Ar pressure results in more grain boundaries and gap structures in the films.In contrast,films deposited in Kr display a higher density of grain boundaries and cluster structures,and the films have an obvious columnar crystal structure,with numerous interfaces and gaps distributed between the columnar structures,providing more paths for gas diffusion.As Kr pressure increases,the film demonstrates more pronounced continuous columnar structure growth,accompanied by deeper and wider grain boundaries.This structural configuration provides a larger specific surface area,which significantly improves the hydrogen adsorption speed and capacity.Consequently,high Ar and Kr pressures are beneficial to improve the adsorption performance.
基金supported by the Open Project of State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology(No.ES202306).
文摘Treatment of precious metals in electronic waste has attracted tremendous attention and is essential for both environmental protection and resource sustainable development.In this study,a novel adsorbent for precious metal ions,V_(2)O_(3)spiny hollow nanospheres(pV_(2)O_(3)SHN),was synthe sized through a one-step hydrothermal-as sis ted methodology for the adsorption of Au(Ⅲ),Ag(Ⅰ),Pd(Ⅱ),and Pt(Ⅳ) from the leaching solution of electronic waste.The results reveal that the p-V2O3SHN hierarchy was successfully constructed with a hollow structure and dense spiny morphology.The prepared p-V2O3SHN can effectively remove precious metal ions such as Au(Ⅲ),Ag(Ⅰ),Pd(Ⅱ),and Pt(Ⅳ),with the selective capture order being Au(Ⅲ)> Ag(Ⅰ)> Pt(Ⅳ)> Pd(Ⅱ)> other metal ions.This superior adsorption capability can be attributed to the multi-diffusible,intermingled composition,and numerous active sites decorating the p-V2O3SHN hierarchy,facilitating the uptake of Au(Ⅲ),Ag(Ⅰ),Pd(Ⅱ),and Pt(Ⅳ) ions from electronic waste.The Langmuir model provided a better fit for the uptake process,revealing maximum uptake capacities of 833.33 mg/g for Au(Ⅲ),370.37 mg/g for Ag(Ⅰ),42.01 mg/g for Pd(Ⅱ),and 77.51 mg/g for Pt(Ⅳ) on p-V_(2)O_(3)SHN.Remarkably,p-V_(2)O_(3)SHN exhibited a robust affinity for the adsorbate due to the presence of surface defects and reduction reactions.The new p-V2O3SHN also demonstrated good reusability for three sorption cycles,highlighting its potential for electronic waste treatment.Due to its facile synthesis and excellent efficiency,hierarchical p-V2O3SHN presents itself as a promising candidate for the selective uptake of Au(Ⅲ),Ag(Ⅰ),Pt(Ⅳ),and Pd(Ⅱ) from electronic waste.
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supported by the National Natural Science Foundation of China(Nos.51778618 and 52070192)the State Key Laboratory of Materials-Oriented Chemical Engineering(No.SKL-MCE-23B09)the open fund of Information Materials and Intelligent Sensing Laboratory of Anhui Province(No.IMIS202213).
文摘Increasing attention has been paid to radioactive wastewater to direct discharge in Japan or accidental leaks.Strontium-90(90Sr)and Cobalt-60(^(60)Co)are the most hazardous nuclides in waste discharged form nuclear reactors.Because of their high solubility and long half-lives,these radioisotopes can persist for hundreds of years before decaying to negligible levels.Herein,a green and biodegradable material nanoscale zero-valent iron(nZVI)supported by bacterial cellulose particles(BCP-nZVI)is constructed for the first time to adsorb Co^(2+)and Sr^(2+)in single and binary systems.BCP-nZVI shows superior adsorption capacities of Co^(2+)and Sr^(2+)in a single system within a wide range of pH values from 5 to 7,while the coexistence of Co^(2+)adsorption inhibits the Sr^(2+)in binary system.Pseudo-second-order dynamics model and Langmuir isothermal model can be indicated the BCP-nZVI adsorption progress with 107.10 mg/g(Co^(2+))and 64.96 mg/g(Sr^(2+))maximum adsorption capacity.BCP-nZVI has outstanding stability,allowing it to be stored for more than one month with compromising its performance.More importantly,BCP-nZVI exhibits exceptional removal efficiency of Co^(2+)(92.53%)and Sr^(2+)(58.62%)removal in natural seawater systems.The mechanism investigation illustrates the high adsorption capacity of BCP-nZVI for Co^(2+)is controlled by redox and hydroxyl complexation.While Sr^(2+)is controlled by hydroxyl complexed adsorption,thus it has weak against interference by cations like Na^(+),Ca^(2+),etc.BCP-nZVI exhibits the advantages of high adsorption capacity,wide pH range,strong stability,and good applicability in natural seawater,which has excellent potential for application in radioactive ions removal.
基金supported by the National Natural Science Foundation of China(22168032)the National Key Research and Development Program of China(2023YFC3904302,2023YFB4103500)the Key Projects of Ning Dong Energy and Chemical Industry Base(2023NDKJXMLX022).
文摘A new adsorbent was successfully prepared by hydrothermal treatment and chemical activation through coal gasification fine slag(CGFS)and blue algae(BA)as raw materials and used for CO_(2)capture.The CO_(2)chemisorption capacity of the adsorbent was further enhanced by taking advantage of the nitrogenous bases contained in the BA.In the hydrothermal process,the addition of BA significantly increased the content of pyrrole nitrogen in the adsorbent.In the activation process,pyrrole nitrogen gradually changed into pyridine nitrogen and graphite nitrogen.Increased BA addition result in a higher specific surface area and microporosity of the adsorbent.The CO_(2)adsorption performance test proved that the CGFS-50%-CA sample has the strongest CO_(2)adsorption capacity at low temperature,up to 15.59 cm^(3)/g,which is mainly through physical adsorption,and the CGFS-10%-CA sample has the strongest CO_(2)adsorption capacity at high temperature,up to 7.31 cm^(3)/g,which is mainly through chemical adsorption.CO_(2)uptake of the CGFS-10%-CA sample was well maintained after 10 cycles,with regeneration efficiencies above 99%.The results indicate that the novel adsorbents with coexistence of physical and chemical adsorption have great potential for CO_(2)adsorption applications.
基金supported by the National Science Fund for Distinguished Young Scholars(No.51925404)the National Natural Science Foundation of China(Nos.52104233,52104228 and 52404261)the Fundamental Research Funds for the Central Universities(No.2023ZDPY05).
文摘This study mainly investigates the influence of pore water characteristics on the adsorption properties of coalbed methane through integrated low field nuclear magnetic resonance(LF-NMR),adsorption experiments,and molecular dynamics(MD)simulations.Pore water states in three coal ranks were characterized during progressive hydration.Multi-scale analysis revealed how pore water evolution regulates methane adsorption processes.During the diffusion-dominated stage(M2-M3),adsorbed water penetrates into the micropores.In the highly wettable brown coal(L1),the adsorbed water content reaches 2.12 g while in the anthracite(A1),it is only 0.29 g.During the active water injection stage(M4-M6),non-adsorbed water dominates in anthracite(over 85%of the total water content of 4.01 g),while adsorbed water remains dominant in lignite(over 60%of the total water content of 3.52 g).Water content plays a key role in methane adsorption in coal.During the water addition phase,the influence of methane adsorption on medium-to-low-rank coal is relatively weak,while the methane adsorption capacity of high-rank coal A1 shows a significant decrease during both the water diffusion and water addition phases,corresponding to a reduction in Langmuir volume of 21.22 cm^(3)/g.Molecular dynamics(MD)results further show that the free energy between molecules on the surface of hydroxyl-modified coal increases,with hydroxyl groups driving electrostatic interactions between coal and water molecules.Increased steric hindrance inhibits hydrogen bond formation and reduces the rate of hydrogen bond growth.There is a significant correlation between pore water content and coal-water molecular interaction energy,which cross-scale validates the results of LF-NMR testing and MD simulations.
基金support from the National Natural Science Foundation of China (22325808,U22B20140,22021004)。
文摘An in-depth understanding of the competition mechanism between olefins and different types of sulfides in gasoline is essential to improve the desulfurization selectivity of the adsorption desulfurization process(ADS).In this study,the competitive adsorption and diffusion mechanism of two systems,diethyl sulfide/cyclohexene and n-butyl mercaptan/cyclohexene,with different adsorption amounts in siliceous faujasite zeolite(FAU) were investigated by Monte Carlo(MC) and molecular dynamics(MD).The systems exhibited a two-stage loading-dependent competitive adsorption and diffusion mechanism,with an inflection point of 32 molecule/UC(moleculers per microcoulomb).Before the inflection point(4-32molecule/UC),the competition mechanism of the two systems was the "optimal-displacement" mechanism.After the inflection point,the mechanism of the diethyl sulfide/cyclohexene changed to "relocation-displacement",while that of the n-butyl mercaptan/cyclohexene system changed to "dominantdisplacement".Compared to ether functional groups,the alcohol functional group has higher polarity and stronger adsorption stability,thus occupying more favorable adsorption sites within the supercages(SCs),while ethyl sulfide shifts outward to other sites within other SCs.In addition,the diffusion performance of adsorbent is related to the adsorption energy.The lower the adsorption energy,the weaker the diffusion ability.Meanwhile,the diffusion performance of adsorbates is better at high temperatures and low adsorption capacity.The effect of temperatu re on the desulfu rization selectivity was determined.A lower temperature is favorable for the adsorption capacity of the two systems and the removal selectivity of sulfides.This study provides fundamental insights into the competitive adsorption and diffusion mechanisms among sulfides,mercaptans and olefins,offering theoretical guidance for adsorbent design and reaction temperature optimization.
