In this work,a novel composite material based on β-cyclodextrin-immobilized sodium alginate aerogel(β-CD/NaAlg) was developed utilizing cross-linker of epichlorohydrin and applied as an adsorbent to remove tetracycl...In this work,a novel composite material based on β-cyclodextrin-immobilized sodium alginate aerogel(β-CD/NaAlg) was developed utilizing cross-linker of epichlorohydrin and applied as an adsorbent to remove tetracycline antibiotics from reclaimed wastewater.A series of characterizations were utilized to confirm the successful synthesis of the adsorbent and this β-CD/NaAlg presented a three-dimensional network at the nanoscale or microscale.Under optimal conditions(pH=4,t=8 h,β-CD:NaAlg=9,adsorbent dosage = 1.5 g·L-1),the maximum removal rate of β-CD/NaAlg to tetracycline was 70%.The adsorption behavior of tetracycline on β-CD/NaAlg conformed to the Freundlich isotherm model(R2=0.9977) and the pseudo-second-order kinetic model(R^(2)=0.9993).Moreover,the adsorbent still removed 55.3% of tetracycline after five cycles.Specially,the adsorbent was integrated with ultrafiltration to adsorb tetracycline antibiotics from simulated reclaimed wastewater,and the removal rate of tetracycline reached 78.9% within 2 h.The existence of Cr(Ⅵ) had a negligible impact on tetracycline removal,while the presence of humic acid exhibited a promoting effect.The possible adsorption mechanisms were also elucidated through X-ray photoelectron spectroscopy and density functional theory analysis.In summary,β-CD/NaAlg represents an environmentally friendly,efficient,and sustainable adsorbent for removing tetracycline antibiotics from reclaimed water.展开更多
Both bottle-point and column-feeding experi-ments involving different solutes and sorbents were carried out to investigate the adsorption selectivity and separation performance of salicylic acid and 5-sulfosalicylic a...Both bottle-point and column-feeding experi-ments involving different solutes and sorbents were carried out to investigate the adsorption selectivity and separation performance of salicylic acid and 5-sulfosalicylic acid.Their adsorption isotherms onto such hypercrosslinked polymeric adsorbents as NDA-100 and NDA-99 could be well described by the Freundlich equations whose characteristics describe extrathermic and favorable adsorption processes.The adsorp-tion towards NDA-100 mainly depended on the p-p interac-tion,while that towards NDA-99 was extremely influenced by the static-electric interaction.Additionally,the adsorptive capacity of salicylic acid on NDA-99 decreased while it increased on NDA-100 with the presence of 5-sulfosalicylic acid in the adsorptive environment as the competitive component.Comparatively,the adsorption capacity of 5-sulfosalicylic acid decreased on both resins with salicylic acid as the competitive component.In fact,the difference in the interaction between adsorbent and adsorbate resulted in the straight antagonism on the effective adsorption sites on the adsorbent.In conclusion,the adsorption selectivity of salicylic acid onto NDA-100 was obviously larger than that onto NDA-99 with the existence of 5-sulfosalicylic acid in the adsorptive environment.A satisfactory separation and recovery of tested solutes in aqueous phase could be foresee-ably achieved by the sequencing adsorption technique involving NDA-100 as well as NDA-99.展开更多
A novel,porous and doubly interpenetrated MOF(FJU-29) was synthesized and characterized by FT-IR,TGA and X-ray single-crystal/powder diffraction.FJU-29 crystallizes in monoclinic,space group C2/c with a = 22.2890(7...A novel,porous and doubly interpenetrated MOF(FJU-29) was synthesized and characterized by FT-IR,TGA and X-ray single-crystal/powder diffraction.FJU-29 crystallizes in monoclinic,space group C2/c with a = 22.2890(7),b = 10.9175(2),c = 21.5601(7) ?,β = 112.908(4)o,V = 4832.7(3) ?~3,Z = 8,Mr = 450.26,D_c = 1.238 g/cm^3,F(000) = 1832,μ(CuKα) = 5.885 mm^(-1),R = 0.0585 and wR = 0.1544 for 4789 observed reflections(I 〉 2s(I)),and R = 0.0726 and wR = 0.1627 for all data.FJU-29 possesses paddle-wheel {Co_2(COO)_4} clusters bridged by bi-pyrazolate naphthalene diimide ligands(H_2NDI) and H_2BDC to from a 3D framework with a pcu-topology.The desolvated FJU-29a shows the BET surface area of 560.44 m^2·g^(-1) accompanies with discriminating uptakes in CO_2 and N_2.The adsorption selectivity determined by ideal adsorbed solution theory(IAST) indicated that FJU-29 a has high CO_2/N_2(18/85) selectivity(75.5) at 296 K and 100 kPa.The relatively high selectivity further implies that FJU-29 a is a potential material for practical flue gas purification.展开更多
The adsorption of aniline, N-methylaniline and N,N-dimethylaniline onto carboxyl resin in Cu2+ form from water, ethanol and n-hexane have been studied. The results show that the adsorption affinities from n-hexane are...The adsorption of aniline, N-methylaniline and N,N-dimethylaniline onto carboxyl resin in Cu2+ form from water, ethanol and n-hexane have been studied. The results show that the adsorption affinities from n-hexane are higher than that from water, and nearly zero from ethanol. The separation factors for the adsorption of these three amines from mixed solution were also examined. The results of continuous column operations show that the breakthrough capacity of aniline from n-hexane reaches 90 mg/g dry resin in Cu2+ form, and the amines adsorbed can be stripped with anhydrous ethanol effectively. Adsorption onto carboxyl resin in Cu2+ form from non-aqueous medium and desorption with anhydrous eluant can overcome the run-off of Cu2+ from the resin, and would show potential advantages in the separation of some water-insoluble natural products.展开更多
Five microporous MOFs were synthesized and their static adsorption properties for light hydrocarbons were experimentally investigated at 298 K and 150 kPa.Among the five MOFs,HKUST-1 and Ni(bdc)(ted)0.5 exhibited much...Five microporous MOFs were synthesized and their static adsorption properties for light hydrocarbons were experimentally investigated at 298 K and 150 kPa.Among the five MOFs,HKUST-1 and Ni(bdc)(ted)0.5 exhibited much higher uptakes of ethane and propane than PCN-250,UiO-66,and ZIF-8.Breakthrough experiments were carried out at 298 K and atmospheric pressure on HKUST-1 and two commercially used adsorbents.HKUST-1 exhibited a much lower dynamic than static adsorption capacity.Moreover,HKUST-1 and the two traditional adsorbents could effectively separate binary(ethane/propane)and ternary(ethane/propane/toluene)mixtures.展开更多
Achieving efficient adsorption and desorption processes by controllably tuning the properties of adsorbents at different technical stages is extremely attractive.However,it is difficult for traditional adsorbents to r...Achieving efficient adsorption and desorption processes by controllably tuning the properties of adsorbents at different technical stages is extremely attractive.However,it is difficult for traditional adsorbents to reach the target because of their fixed active sites.Herein,we report on the fabrication of a smart adsorbent,which was achieved by introducing photoresponsive azobenzene derivatives with cis/trans isomers to Ce-doped mesoporous silica.These photoresponsive groups serve as “molecular switches”by sheltering and exposing active sites,leading to efficient adsorption and desorption.Ce is also doped to provide additional active sites in order to enhance the adsorption performance.The results show that the cis isomers effectively shelter the active sites,leading to the selective adsorption of methylene blue(MB)over brilliant blue(BB),while the trans isomers completely expose the active sites,resulting in the convenient release of the adsorbates.Both selective adsorption and efficient desorption can be realized controllably by these smart adsorbents through photostimulation.Moreover,the performance of the obtained materials is well maintained after five cycles.展开更多
Surface modification offers an alternative strategy to improve both ageing resistance and electrochemical performance of cathode materials for lithium-ion batteries.From the viewpoint of real application,surface modif...Surface modification offers an alternative strategy to improve both ageing resistance and electrochemical performance of cathode materials for lithium-ion batteries.From the viewpoint of real application,surface modification of the cathode materials should be designed with scientificity,effectiveness,low cost,less Li+leaching,and remained tap density.In this contribution,a selective adsorption-involved in-situ growth of polyaniline(PANI)nanoparticles on LiNi_(0.5)Mn_(0.3)Co_(0.2)O_(2)(NMC532)has been designed through a room-temperature-and-pressure chemical vapor deposition technique.The selective growth of PANTI on NMC532 is based on theoretical computation results that multivalent Ni,Mn,and Co are capable of specifically conjugating and activating aniline molecules and,hence,initiating in-situ oxidation polymerization.With only trace amount of aniline monomer,the resulting PANI nanoparticles-inlaid NMC532 microparticles can endure four-month ageing in ambient atmosphere and exhibit improved electrochemical performance at both room temperature and 55℃ compared with pristine NMC532.The improved electrochemical performance of NMC532/PANI is attributed to the enhanced structural stability of NMC532 and inhibited side reactions related to Li_(2)CO_(3) formation,PVDF degradation,electrolyte decomposition,and transition-metal dissolution,owing to PANI modification.展开更多
The AgBr powder was prepared by a hydrothermal method via a reaction of AgNO3 with hexadecyltrimethy ammonium bromide(CTAB),namely,CTAB-assisted synthesis method.The selective-adsorption ability of the AgBr samples ...The AgBr powder was prepared by a hydrothermal method via a reaction of AgNO3 with hexadecyltrimethy ammonium bromide(CTAB),namely,CTAB-assisted synthesis method.The selective-adsorption ability of the AgBr samples for the MO was evaluated in a MO and Rhodamine B mixed solution via ultraviolet-visible spectra.Compared with the AgBr sample prepared from NaBr solution,it was found that the AgBr powder synthesized by CTAB-assisted method exhibited high selective-adsorption performance for the MO in the MO-RhB mixed system.After aged for 60 min,the MO could be efficiently removed by CTAB-assisted AgBr powder.Considering the potential wide applications of the selective adsorption,the CTAB-assisted AgBr provides a new and efficient method for the removal of various dyes and is possible to be widely used in industries.展开更多
Rare earth elements(REE)are strategic resources and the recycling of REE in alternative resources is urgent and gets increasingly attention.However,the separation of REE in these alternative resources is still a chall...Rare earth elements(REE)are strategic resources and the recycling of REE in alternative resources is urgent and gets increasingly attention.However,the separation of REE in these alternative resources is still a challenge due to the low concentration of REE and multi coexisted ions in acidic system.In this study,the species distribution of REE within the pH 0-8.0 was calculated.The SBA-15 originated from coal fly ash was modified by two steps with(3-aminopropyl)triethoxysilane(APTES)and diethylenetriaminepentaacetic dianhydride(DTPADA)to obtain DTPADA-SBA-15 adsorbent,which was applied to the selective adsorption of REE.The results showed that DTPADA-SBA-15 possessed excellent adsorption performance on the selective adsorption of REE,including Eu,Gd,Tb,Nd and Sm,in acidic solution(pH 2)with multi competing ions.The FT-IR and Zeta potential characterization verified that the chemical adsorption through the coordination of O in DTPADA-SBA-15 with REE was dominant at lower pH value.The study of adsorption kinetics indicated that the adsorption of rare earth metal ions followed pseudosecond-order kinetic,of which the adsorption process followed the Langmuir isotherm model.展开更多
A novel biosorbent was synthesized by grafting bisthiourea(BTU)on a silk sericin(SS)matrix.This biosorbent was denoted as BTU-SS and characterized by Fourier transform infrared spectroscopy(FTIR),zeta potential measur...A novel biosorbent was synthesized by grafting bisthiourea(BTU)on a silk sericin(SS)matrix.This biosorbent was denoted as BTU-SS and characterized by Fourier transform infrared spectroscopy(FTIR),zeta potential measurements,elemental analysis,and X-ray photoelectron spectroscopy(XPS).As revealed by the adsorption experiments,both BTU-SS and SS showed low affinity towards coexisting base metallic ions in Ag(I)-Cu(II)-Zn(II)-Ni(II)-Pb(II)electronic waste leachate mixtures,while their adsorption capacities towards Ag(I)reached 30.5 and 10.4 mg∙g-1 at a pH of 5.0,respectively.BTU-SS showed higher selectivity towards Ag(I)than SS,as revealed by the Ag(I)partition coefficients between the biosorbents and the leachate(16634.6 and 403.3,respectively).As further demonstrated by column experiments,BTU-SS allowed the separation of Ag(I)from an electronic waste leachate.Thermodynamic studies showed that the adsorption of Ag(I)was exothermic and spontaneous,while adsorption kinetic experiments revealed that chemisorption dominated the adsorption process with activation energies of 47.67 and 53.27 kJ∙mol-1 for BTU-SS and SS,respectively.FTIR and XPS analyses of fresh and Ag(I)-loaded BTU-SS further revealed an adsorption mechanism mainly involving electrostatic and coordination interactions.展开更多
Rhenium separation from molybdenum in molybdenite minerals and waste leachate has become an emerging challenge.Addressing this challenge,we prepared a set of protein-based alkylamine/alkylammonium salts complexes as e...Rhenium separation from molybdenum in molybdenite minerals and waste leachate has become an emerging challenge.Addressing this challenge,we prepared a set of protein-based alkylamine/alkylammonium salts complexes as extractants for selective uptake of rhenium from molybdenum,where the protein component turned into the insoluble amyloid-like structure when its internal disulfide bonds were reduced,namely phase-transition process.Among them,the phase-transited lysozyme and methyletrioctyleammonium chloride complex(PTL-N263)exhibited the most efficient adsorption at the alkaline condition for the electrostatic interaction between negatively charged metal ions with positively charged center(R_(4)N^(+))in N263,where negatively charged protein residues hindered the ion exchange of Cl^(-)in N263 for larger size Mo species(Mo_(7)O_(24)^(6-))than smaller size Re species(ReO^(4-)).The adsorption follows the Freundlich model and pseudo-second-order kinetics,which exhibits toplevel adsorption performance with a maximum adsorption capacity of 124 mg/g and a separation factor(β_(Re/Mo))of 2.78×10^(3)for Re.The adsorption capacity per unit area(57.2 mg/(g m^(2)))is 1.6–41 times higher than previously reported adsorbents,and the cost for adsorbing 1 g of Re(VII)is$1.07,indicating its industrial capability.This adsorption strategy can be applied to separating Re from Mo in binary solutions and industrial wastewater with other competing ions.展开更多
Despite the development of various Lewis acidic nano-adsorbents for fluoride removal through innersphere coordination,strong competition for hydroxyl ions still hinders efficient water defluoridation.In addition,the c...Despite the development of various Lewis acidic nano-adsorbents for fluoride removal through innersphere coordination,strong competition for hydroxyl ions still hinders efficient water defluoridation.In addition,the critical issue of polysilicate scaling that results from the ubiquitous silicates must be addressed.To tackle these issues,an alternative approach to enhancing adsorption reactivity by modifying nano-adsorbents with dual Lewis and Bronsted acidity is proposed.The feasibility of this approach is demonstrated by growing zirconium phosphate(ZrP)inside a gel-type anion exchanger,N201,to produce nanocomposite ZrP@N201,in which the confined ZrP contained an otherwise metastable amorphous phase with Lewis acidic Zr^(4+) sites and Bronsted acidic monohydrogen phosphate groups(-O_(3)POH).Compared with the Lewis acidic nano-zirconium oxide analog(HZ0@N201),ZrP@N201 exhibited a greatly improved adsorption capacity(117.9 vs.52.3 mg/g-Zr)and mass transfer rate(3.56×10^(-6) vs.4.55×10^(-7) cm/s),while bulk ZrP produced a thermodynamically stableα-phase with Bronsted acidity that exhibited negligible adsorption capability toward fluoride.The enhanced defluoridation activity of ZrP@N201 is attributed to Bronsted acidity and the increased outer electron density of ZA+sites,as corroborated using XPS and solid-state NMR analysis.Moreover,Bronsted acidity strengthens the resistance of ZrP@N201 to silicate,allowing its full regeneration during cyclic defluoridation.Column tests demonstrated 3-10 times the amount of clean water from(waste)for ZrP@N201 as compared to both HZO@N201 and the widely used activated aluminum oxide.This study highlights the potential of developing nano-adsorbents with dual acidities for various environmental remediation applications.展开更多
Adsorption process is considered to be the most promising alternative for the CO_(2) capture to the traditional energy-intensive amine absorption process,and the development of feasible and efficient CO_(2) adsorbents...Adsorption process is considered to be the most promising alternative for the CO_(2) capture to the traditional energy-intensive amine absorption process,and the development of feasible and efficient CO_(2) adsorbents is still a challenge.In this work,the NiO@USY(ultrastable Y)composites with different NiO loadings were prepared for the CO_(2) adsorption using Ni(NO_(3))_(2) as the precursor.The composites were characterized by X-ray photoelectron spectroscopy,X-ray diffraction,nitrogen adsorption–desorption test,scanning electron microscopy analysis,and thermogravimetric analysis,and were evaluated for the CO_(2) adsorption capacity,CO_(2)/N2 adsorption selectivity and CO_(2) cycle adsorption capacity.The characterization results show that after the activation at 423 K,the Ni(NO_(3))_(2) species were well dispersed into the surface of zeolite USY,and after the further activation at 823 K,Ni(NO_(3))_(2) could be converted into highly dispersed NiO.The adsorption results show that the presence of the active component NiO plays an important role in improving the CO_(2) adsorption performance,and the NiO@USY composite with a NiO loading of 1.5 mmol·g^(-1) USY support displays a high adsorption capacity and adsorption selectivity for CO_(2),and shows a good cycle stability.In addition,the Clausius–Clapeyron equation was used to evaluate the isosteric heat of adsorption of CO_(2) on the NiO(1.5)@USY composite,and the heat of adsorption was 17.39–38.34 kJ·mol^(-1).展开更多
The surface ion-imprinting concept and chitosan incorporated sol-gel process were applied to the synthesis of a new attapulgitesupported polymer for selective separation of Ce(III) from aqueous solution. The imprint...The surface ion-imprinting concept and chitosan incorporated sol-gel process were applied to the synthesis of a new attapulgitesupported polymer for selective separation of Ce(III) from aqueous solution. The imprinting mechanism of prepared ion-imprinted polymer were discussed with the Characteristics of FT-IR and SEM. Results from the experiments of adsorption capacity and selectivity suggested that ion-imprinted polymer offered a fast kinetics for the adsorption of Ce(III) under the optimum conditions. Its maximum adsorption capacity was 38.02 mg/g, and the selective recognition towards Ce(III) was much higher than that of the non-imprinted polymer and attapulgite. The prepared functional polymer was shown to be promising for selective separation and enrichment of trace Ce(III) in environmental samples. ?2009 Yong Sheng Yan. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
Surfactant enhanced elution is an effective method for removing hydrophobic organic pollutants from soils.The key to the development of leaching technology is selective removal of targeted pollutants in soil washing e...Surfactant enhanced elution is an effective method for removing hydrophobic organic pollutants from soils.The key to the development of leaching technology is selective removal of targeted pollutants in soil washing effluent and recycling of surfactant solutions.In this study,a molecular imprinting technique was applied to selectively sorb polybrominated diphenyl ethers(PBDEs)in soil washing effluent.The novel molecular imprinted polymers(MIPs)using different template molecules were synthesized by precipitation polymerization.Adsorption behaviors andmechanisms ofMIPs were studied through experiments and theoretical calculations.The results show that 4-bromo-4'-hydroxybiphenyl and toluene can be effective imprinting molecule for MIPs synthesis.The maximal adsorption capacity of selected dummy molecular imprinted polymer(D1-MIP)was 1032.36μmol/g,and that of part molecular imprinted polymer(P-MIP)was 981.13μmol/g.Their imprinting factors in 5 PBDEs adsorption ranged from 2.13 to 5.88,the recovery percentage of Triton X-100 can reach 99.09%,confirming the feasibility of reusing surfactant.Various PBDEs could be removed by MIPs,and Quantitative Structure Property Relationship analysis revealed that PBDEs’molecular volume,planarity,polarity,and hydrophobicity have major influences on their adsorption performance.DFT calculation revealed that Van derWaals force and hydrogen bonding played important roles during selective adsorption.These results can provide effective theoretical guidance for surfactant enhanced soil elution in practical engineering applications.展开更多
The development of bio-adsorbents with highly selective immobilization properties for specific heavy metals is a great challenge,but has important application value.Biogenic whewellite(BW)with high selectivity for Pb(...The development of bio-adsorbents with highly selective immobilization properties for specific heavy metals is a great challenge,but has important application value.Biogenic whewellite(BW)with high selectivity for Pb(Ⅱ)was synthesized by mineral microbial transformation.The selective immobilization properties and mechanism of BW for Pb(Ⅱ)were analyzed by combining mineral characterization technology and batch adsorption research methods.The results indicated that BW can efficiently and selectively immobilize Pb(Ⅱ)in single or composite heavy metal adsorption solutions,and the immobilized Pb(Ⅱ)is difficult to desorb.BW undergoes monolayer adsorption on Pb(Ⅱ),Qmax≈1073.17 mg/g.The immobilization of Pb(Ⅱ)by BW is a physico-chemical adsorption process with spontaneous heat absorption and an accompanying increase in entropy.In addition,the sequestration of Pb(Ⅱ)by BW remains around 756.99 mg/g even at p H=1.The excellent selective immobilization properties of BW for Pb(Ⅱ)are closely related to its smaller Ksp,electrostatic repulsion effect,organic-inorganic composite structure,acid resistance and the formation of Pb(Ⅱ)oxalate.This study provides beneficial information about the recycling of lead in acidic lead-containing wastewater and composite heavy metal contaminated water bodies.展开更多
The composition of biomass pyrolysis gas is complex,and the selective separation of its components is crucial for its further utilization.Metal-incorporated nitrogen-doped materials exhibit enormous potential,whereas ...The composition of biomass pyrolysis gas is complex,and the selective separation of its components is crucial for its further utilization.Metal-incorporated nitrogen-doped materials exhibit enormous potential,whereas the relevant adsorption mechanism is still unclear.Herein,16 metal-incorporated nitrogen-doped carbon materials were designed based on the density functional theory calculation,and the adsorption mechanism of pyrolysis gas components H2,CO,CO_(2),CH_(4),and C2H6 was explored.The results indicate that metal-incorporated nitrogen-doped carbon materials generally have better adsorption effects on CO and CO_(2)than on H_(2),CH_(4),and C_(2)H_(6).Transition metal Mo-and alkaline earth metal Mg-and Ca-incorporated nitrogen-doped carbon materials show the potential to separate CO and CO_(2).The mixed adsorption results of CO_(2)and CO further indicate that when the CO_(2)ratio is significantly higher than that of CO,the saturated adsorption of CO_(2)will precede that of CO.Overall,the three metal-incorporated nitrogen-doped carbon materials can selectively separate CO_(2),and the alkaline earth metal Mg-incorporated nitrogen-doped carbon material has the best performance.This study provides theoretical guidance for the design of carbon capture materials and lays the foundation for the efficient utilization of biomass pyrolysis gas.展开更多
A novel Ni(Ⅱ) ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid(AMPS) as a func...A novel Ni(Ⅱ) ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid(AMPS) as a functional monomer for the selective separation of Ni(Ⅱ) from aqueous solution. The sorbent showed good chemical and thermal stability. Kinetics studies indicated that the equilibrium adsorption was achieved within 10 min and the adsorption kinetics fitted well with the pseudo-second-order kinetic model. The maximum adsorption capacity of the ion-imprinted polymer towards Ni(Ⅱ) at the optimal p H of 7.0 was 66.22 mg·g^(-1). The relative selectivity coefficients of the sorbent were 9.23, 15.71, 14.72 and 20.15 for Ni(Ⅱ)/Co(Ⅱ), Ni(Ⅱ)/Cu(Ⅱ), Ni(Ⅱ)/Zn(Ⅱ) and Ni(Ⅱ)/Pb(Ⅱ), respectively. The adsorption isotherm fitted well with Langmuir isotherm model. The thermodynamic results indicated that the adsorption of Ni(Ⅱ) was a spontaneous and endothermic process. The sorbent showed good reusability evidenced by six cycles of adsorption/desorption experiments. The precision of this method is satisfactory. Thus, the prepared sorbent can be considered as a promising sorbent for selective separation of Ni(Ⅱ) in real water samples.展开更多
A multi-site functionalized microporous metal-organic framework(MOF),H[Zn2(BDP)0.5(ATZ)3]·0.5 H_(2)O·0.5DMF(1),was synthesized through mixed ligands strategy.The pore surface of complex 1 was modified by unc...A multi-site functionalized microporous metal-organic framework(MOF),H[Zn2(BDP)0.5(ATZ)3]·0.5 H_(2)O·0.5DMF(1),was synthesized through mixed ligands strategy.The pore surface of complex 1 was modified by uncoordinated carboxylate O atoms,phenyl and pyridyl rings as well as-NH_(2) groups,which strengthen interactions with C2H6,C_(2)H_(4) and CO_(2) molecules and lead to efficiently selective C2H6,C_(2)H_(4) and CO_(2) uptake over CH_(4).The selective adsorption mechanism was discussed deeply based on Grand Canonical Monte Carlo(GCMC)simulations.It is expected that this study will provide a new perspective for the rational design and synthesis of MOFs with efficient gas adsorption and separation performance.展开更多
The prediction of two-dimensional molecular self-assembly structures has always been a problem to be solved.The molecules with meta-dicarboxyl groups can self-assemble into a specific hexagonal cavity,which has an imp...The prediction of two-dimensional molecular self-assembly structures has always been a problem to be solved.The molecules with meta-dicarboxyl groups can self-assemble into a specific hexagonal cavity,which has an important influence on the prediction of molecular self-assembly structures and the application of functional molecules with meta-dicarboxyl groups.Two kinds of molecules with four pairs of meta-dicarboxyl groups,1,3,6,8-tet「akis(3,5-isophthalic acid)pyrene(H_(8)TIAPy)and 4′,4′",4′"",4""-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1′-biphenyl]-3,5-dicarboxylic acid))(H8ETTB)molecules were chosen to observe the self-assembly behavior at the heptanoic acid/highly oriented pyrolytic graphite(HA/HOPG)interface.H8TIAPy molecules self-assembled into well-ordered quadrilateral structures and could be regulated into kagome networks with hexagonal pores by coronene(COR)molecules.H8ETTB molecules self-assembled into lamellar structures and transformed into acid-COR-acid-COR co-assembled structures at low concentration of COR solution and acid-COR dimer-acid-COR dimer co-assembled structures at high concentration of COR solution.The reason that H8ETTB molecules could not be regulated into hexagonal porous architecture was attributed to the steric hindrance by the similar length and width of H8ETTB molecules.The H8ETTB templates had stronger adsorption for COR than that of hexaphenylbenzene(HPB),regardless of the order of molecular introduction.展开更多
基金supported by the National Key Research and Development Program of China(2022YFC3801101)National Natural Science Foundation of China(52170028)+1 种基金the State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology(2023DX11)National Engineering Research Center for Safe Sludge Disposal and Resource Recovery(2021A003).
文摘In this work,a novel composite material based on β-cyclodextrin-immobilized sodium alginate aerogel(β-CD/NaAlg) was developed utilizing cross-linker of epichlorohydrin and applied as an adsorbent to remove tetracycline antibiotics from reclaimed wastewater.A series of characterizations were utilized to confirm the successful synthesis of the adsorbent and this β-CD/NaAlg presented a three-dimensional network at the nanoscale or microscale.Under optimal conditions(pH=4,t=8 h,β-CD:NaAlg=9,adsorbent dosage = 1.5 g·L-1),the maximum removal rate of β-CD/NaAlg to tetracycline was 70%.The adsorption behavior of tetracycline on β-CD/NaAlg conformed to the Freundlich isotherm model(R2=0.9977) and the pseudo-second-order kinetic model(R^(2)=0.9993).Moreover,the adsorbent still removed 55.3% of tetracycline after five cycles.Specially,the adsorbent was integrated with ultrafiltration to adsorb tetracycline antibiotics from simulated reclaimed wastewater,and the removal rate of tetracycline reached 78.9% within 2 h.The existence of Cr(Ⅵ) had a negligible impact on tetracycline removal,while the presence of humic acid exhibited a promoting effect.The possible adsorption mechanisms were also elucidated through X-ray photoelectron spectroscopy and density functional theory analysis.In summary,β-CD/NaAlg represents an environmentally friendly,efficient,and sustainable adsorbent for removing tetracycline antibiotics from reclaimed water.
基金The work was supported by the Opening Fund of Key Laboratory of Environmental Engineering of Jiangsu Province,China(Grant No.KF0502)by the Opening Fund of Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection(Grant No.JLCBE05005).
文摘Both bottle-point and column-feeding experi-ments involving different solutes and sorbents were carried out to investigate the adsorption selectivity and separation performance of salicylic acid and 5-sulfosalicylic acid.Their adsorption isotherms onto such hypercrosslinked polymeric adsorbents as NDA-100 and NDA-99 could be well described by the Freundlich equations whose characteristics describe extrathermic and favorable adsorption processes.The adsorp-tion towards NDA-100 mainly depended on the p-p interac-tion,while that towards NDA-99 was extremely influenced by the static-electric interaction.Additionally,the adsorptive capacity of salicylic acid on NDA-99 decreased while it increased on NDA-100 with the presence of 5-sulfosalicylic acid in the adsorptive environment as the competitive component.Comparatively,the adsorption capacity of 5-sulfosalicylic acid decreased on both resins with salicylic acid as the competitive component.In fact,the difference in the interaction between adsorbent and adsorbate resulted in the straight antagonism on the effective adsorption sites on the adsorbent.In conclusion,the adsorption selectivity of salicylic acid onto NDA-100 was obviously larger than that onto NDA-99 with the existence of 5-sulfosalicylic acid in the adsorptive environment.A satisfactory separation and recovery of tested solutes in aqueous phase could be foresee-ably achieved by the sequencing adsorption technique involving NDA-100 as well as NDA-99.
基金Financially supported by the National Natural Science Foundation of China(21273033,21673039 and 21573042)
文摘A novel,porous and doubly interpenetrated MOF(FJU-29) was synthesized and characterized by FT-IR,TGA and X-ray single-crystal/powder diffraction.FJU-29 crystallizes in monoclinic,space group C2/c with a = 22.2890(7),b = 10.9175(2),c = 21.5601(7) ?,β = 112.908(4)o,V = 4832.7(3) ?~3,Z = 8,Mr = 450.26,D_c = 1.238 g/cm^3,F(000) = 1832,μ(CuKα) = 5.885 mm^(-1),R = 0.0585 and wR = 0.1544 for 4789 observed reflections(I 〉 2s(I)),and R = 0.0726 and wR = 0.1627 for all data.FJU-29 possesses paddle-wheel {Co_2(COO)_4} clusters bridged by bi-pyrazolate naphthalene diimide ligands(H_2NDI) and H_2BDC to from a 3D framework with a pcu-topology.The desolvated FJU-29a shows the BET surface area of 560.44 m^2·g^(-1) accompanies with discriminating uptakes in CO_2 and N_2.The adsorption selectivity determined by ideal adsorbed solution theory(IAST) indicated that FJU-29 a has high CO_2/N_2(18/85) selectivity(75.5) at 296 K and 100 kPa.The relatively high selectivity further implies that FJU-29 a is a potential material for practical flue gas purification.
基金This study was supported by National Natural Science Foundation (Grant No. 29974015)
文摘The adsorption of aniline, N-methylaniline and N,N-dimethylaniline onto carboxyl resin in Cu2+ form from water, ethanol and n-hexane have been studied. The results show that the adsorption affinities from n-hexane are higher than that from water, and nearly zero from ethanol. The separation factors for the adsorption of these three amines from mixed solution were also examined. The results of continuous column operations show that the breakthrough capacity of aniline from n-hexane reaches 90 mg/g dry resin in Cu2+ form, and the amines adsorbed can be stripped with anhydrous ethanol effectively. Adsorption onto carboxyl resin in Cu2+ form from non-aqueous medium and desorption with anhydrous eluant can overcome the run-off of Cu2+ from the resin, and would show potential advantages in the separation of some water-insoluble natural products.
基金supported by the National Natural Science Foundation of China(grant number:21701189).
文摘Five microporous MOFs were synthesized and their static adsorption properties for light hydrocarbons were experimentally investigated at 298 K and 150 kPa.Among the five MOFs,HKUST-1 and Ni(bdc)(ted)0.5 exhibited much higher uptakes of ethane and propane than PCN-250,UiO-66,and ZIF-8.Breakthrough experiments were carried out at 298 K and atmospheric pressure on HKUST-1 and two commercially used adsorbents.HKUST-1 exhibited a much lower dynamic than static adsorption capacity.Moreover,HKUST-1 and the two traditional adsorbents could effectively separate binary(ethane/propane)and ternary(ethane/propane/toluene)mixtures.
基金This work was supported by the National Science Fund for Excellent Young Scholars(21722606)the National Natural Science Foundation of China(21676138,21878149,21808110,and 21576137)+1 种基金the China Postdoctoral Science Foundation(2018M632295)the Six Talent Plan(2016XCL031).
文摘Achieving efficient adsorption and desorption processes by controllably tuning the properties of adsorbents at different technical stages is extremely attractive.However,it is difficult for traditional adsorbents to reach the target because of their fixed active sites.Herein,we report on the fabrication of a smart adsorbent,which was achieved by introducing photoresponsive azobenzene derivatives with cis/trans isomers to Ce-doped mesoporous silica.These photoresponsive groups serve as “molecular switches”by sheltering and exposing active sites,leading to efficient adsorption and desorption.Ce is also doped to provide additional active sites in order to enhance the adsorption performance.The results show that the cis isomers effectively shelter the active sites,leading to the selective adsorption of methylene blue(MB)over brilliant blue(BB),while the trans isomers completely expose the active sites,resulting in the convenient release of the adsorbates.Both selective adsorption and efficient desorption can be realized controllably by these smart adsorbents through photostimulation.Moreover,the performance of the obtained materials is well maintained after five cycles.
基金financially supported by the Natural Science Foundation of Shandong Province(ZR2019MEM015 and ZR2017QB003)Young Taishan Scholar Program of Shandong Province(No.tsqn201909139)the Introduction and Cultivation Plan of Young Innovative Talents in Colleges and Universities of Shandong Province。
文摘Surface modification offers an alternative strategy to improve both ageing resistance and electrochemical performance of cathode materials for lithium-ion batteries.From the viewpoint of real application,surface modification of the cathode materials should be designed with scientificity,effectiveness,low cost,less Li+leaching,and remained tap density.In this contribution,a selective adsorption-involved in-situ growth of polyaniline(PANI)nanoparticles on LiNi_(0.5)Mn_(0.3)Co_(0.2)O_(2)(NMC532)has been designed through a room-temperature-and-pressure chemical vapor deposition technique.The selective growth of PANTI on NMC532 is based on theoretical computation results that multivalent Ni,Mn,and Co are capable of specifically conjugating and activating aniline molecules and,hence,initiating in-situ oxidation polymerization.With only trace amount of aniline monomer,the resulting PANI nanoparticles-inlaid NMC532 microparticles can endure four-month ageing in ambient atmosphere and exhibit improved electrochemical performance at both room temperature and 55℃ compared with pristine NMC532.The improved electrochemical performance of NMC532/PANI is attributed to the enhanced structural stability of NMC532 and inhibited side reactions related to Li_(2)CO_(3) formation,PVDF degradation,electrolyte decomposition,and transition-metal dissolution,owing to PANI modification.
基金Funded by the National Natural Science Foundation of China (No.20803055)the Fundamental Research Funds for the Central Universities(Nos.2011-1a-39 and 2011-1a-16)
文摘The AgBr powder was prepared by a hydrothermal method via a reaction of AgNO3 with hexadecyltrimethy ammonium bromide(CTAB),namely,CTAB-assisted synthesis method.The selective-adsorption ability of the AgBr samples for the MO was evaluated in a MO and Rhodamine B mixed solution via ultraviolet-visible spectra.Compared with the AgBr sample prepared from NaBr solution,it was found that the AgBr powder synthesized by CTAB-assisted method exhibited high selective-adsorption performance for the MO in the MO-RhB mixed system.After aged for 60 min,the MO could be efficiently removed by CTAB-assisted AgBr powder.Considering the potential wide applications of the selective adsorption,the CTAB-assisted AgBr provides a new and efficient method for the removal of various dyes and is possible to be widely used in industries.
基金the National Natural Science Foundation of China(U1810205)Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi Province(2020L0022)Key Research and Development Program of Shanxi Province(201903D311006).
文摘Rare earth elements(REE)are strategic resources and the recycling of REE in alternative resources is urgent and gets increasingly attention.However,the separation of REE in these alternative resources is still a challenge due to the low concentration of REE and multi coexisted ions in acidic system.In this study,the species distribution of REE within the pH 0-8.0 was calculated.The SBA-15 originated from coal fly ash was modified by two steps with(3-aminopropyl)triethoxysilane(APTES)and diethylenetriaminepentaacetic dianhydride(DTPADA)to obtain DTPADA-SBA-15 adsorbent,which was applied to the selective adsorption of REE.The results showed that DTPADA-SBA-15 possessed excellent adsorption performance on the selective adsorption of REE,including Eu,Gd,Tb,Nd and Sm,in acidic solution(pH 2)with multi competing ions.The FT-IR and Zeta potential characterization verified that the chemical adsorption through the coordination of O in DTPADA-SBA-15 with REE was dominant at lower pH value.The study of adsorption kinetics indicated that the adsorption of rare earth metal ions followed pseudosecond-order kinetic,of which the adsorption process followed the Langmuir isotherm model.
基金This work was supported by the Natural Science Foundation of Education Department of Shaanxi Provincial Government(2013JK0873).
文摘A novel biosorbent was synthesized by grafting bisthiourea(BTU)on a silk sericin(SS)matrix.This biosorbent was denoted as BTU-SS and characterized by Fourier transform infrared spectroscopy(FTIR),zeta potential measurements,elemental analysis,and X-ray photoelectron spectroscopy(XPS).As revealed by the adsorption experiments,both BTU-SS and SS showed low affinity towards coexisting base metallic ions in Ag(I)-Cu(II)-Zn(II)-Ni(II)-Pb(II)electronic waste leachate mixtures,while their adsorption capacities towards Ag(I)reached 30.5 and 10.4 mg∙g-1 at a pH of 5.0,respectively.BTU-SS showed higher selectivity towards Ag(I)than SS,as revealed by the Ag(I)partition coefficients between the biosorbents and the leachate(16634.6 and 403.3,respectively).As further demonstrated by column experiments,BTU-SS allowed the separation of Ag(I)from an electronic waste leachate.Thermodynamic studies showed that the adsorption of Ag(I)was exothermic and spontaneous,while adsorption kinetic experiments revealed that chemisorption dominated the adsorption process with activation energies of 47.67 and 53.27 kJ∙mol-1 for BTU-SS and SS,respectively.FTIR and XPS analyses of fresh and Ag(I)-loaded BTU-SS further revealed an adsorption mechanism mainly involving electrostatic and coordination interactions.
基金supported by the National Science Fund for Distinguished Young Scholars(Grant No.52225301)the National Key R&D Program of China(Grant Nos.2020YFA0710400 and 2020YFA0710402)+5 种基金the National Natural Science Foundation of China(Grant Nos.21905166,2187513251903147)the 111 Project(Grant No.B14041)the Fundamental Research Funds for the Central Universities(Grant Nos.GK201801003,2020TS092,and GK202205013)the Innovation Capability Support Program of Shaanxi(Grant No.2020TD024)the Science and Technology Innovation Team of Shaanxi Province(Grant No.2022TD-35)。
文摘Rhenium separation from molybdenum in molybdenite minerals and waste leachate has become an emerging challenge.Addressing this challenge,we prepared a set of protein-based alkylamine/alkylammonium salts complexes as extractants for selective uptake of rhenium from molybdenum,where the protein component turned into the insoluble amyloid-like structure when its internal disulfide bonds were reduced,namely phase-transition process.Among them,the phase-transited lysozyme and methyletrioctyleammonium chloride complex(PTL-N263)exhibited the most efficient adsorption at the alkaline condition for the electrostatic interaction between negatively charged metal ions with positively charged center(R_(4)N^(+))in N263,where negatively charged protein residues hindered the ion exchange of Cl^(-)in N263 for larger size Mo species(Mo_(7)O_(24)^(6-))than smaller size Re species(ReO^(4-)).The adsorption follows the Freundlich model and pseudo-second-order kinetics,which exhibits toplevel adsorption performance with a maximum adsorption capacity of 124 mg/g and a separation factor(β_(Re/Mo))of 2.78×10^(3)for Re.The adsorption capacity per unit area(57.2 mg/(g m^(2)))is 1.6–41 times higher than previously reported adsorbents,and the cost for adsorbing 1 g of Re(VII)is$1.07,indicating its industrial capability.This adsorption strategy can be applied to separating Re from Mo in binary solutions and industrial wastewater with other competing ions.
基金We greatly appreciate the financial support from the National Key Research and Development Program of China(No.2022YFC3205300)the National Natural Science Foundation of China(No.22122604).
文摘Despite the development of various Lewis acidic nano-adsorbents for fluoride removal through innersphere coordination,strong competition for hydroxyl ions still hinders efficient water defluoridation.In addition,the critical issue of polysilicate scaling that results from the ubiquitous silicates must be addressed.To tackle these issues,an alternative approach to enhancing adsorption reactivity by modifying nano-adsorbents with dual Lewis and Bronsted acidity is proposed.The feasibility of this approach is demonstrated by growing zirconium phosphate(ZrP)inside a gel-type anion exchanger,N201,to produce nanocomposite ZrP@N201,in which the confined ZrP contained an otherwise metastable amorphous phase with Lewis acidic Zr^(4+) sites and Bronsted acidic monohydrogen phosphate groups(-O_(3)POH).Compared with the Lewis acidic nano-zirconium oxide analog(HZ0@N201),ZrP@N201 exhibited a greatly improved adsorption capacity(117.9 vs.52.3 mg/g-Zr)and mass transfer rate(3.56×10^(-6) vs.4.55×10^(-7) cm/s),while bulk ZrP produced a thermodynamically stableα-phase with Bronsted acidity that exhibited negligible adsorption capability toward fluoride.The enhanced defluoridation activity of ZrP@N201 is attributed to Bronsted acidity and the increased outer electron density of ZA+sites,as corroborated using XPS and solid-state NMR analysis.Moreover,Bronsted acidity strengthens the resistance of ZrP@N201 to silicate,allowing its full regeneration during cyclic defluoridation.Column tests demonstrated 3-10 times the amount of clean water from(waste)for ZrP@N201 as compared to both HZO@N201 and the widely used activated aluminum oxide.This study highlights the potential of developing nano-adsorbents with dual acidities for various environmental remediation applications.
基金This work was funded by the Qingdao Science and Technology Plan Application Foundation Research Project(19-6-2-28-cg).
文摘Adsorption process is considered to be the most promising alternative for the CO_(2) capture to the traditional energy-intensive amine absorption process,and the development of feasible and efficient CO_(2) adsorbents is still a challenge.In this work,the NiO@USY(ultrastable Y)composites with different NiO loadings were prepared for the CO_(2) adsorption using Ni(NO_(3))_(2) as the precursor.The composites were characterized by X-ray photoelectron spectroscopy,X-ray diffraction,nitrogen adsorption–desorption test,scanning electron microscopy analysis,and thermogravimetric analysis,and were evaluated for the CO_(2) adsorption capacity,CO_(2)/N2 adsorption selectivity and CO_(2) cycle adsorption capacity.The characterization results show that after the activation at 423 K,the Ni(NO_(3))_(2) species were well dispersed into the surface of zeolite USY,and after the further activation at 823 K,Ni(NO_(3))_(2) could be converted into highly dispersed NiO.The adsorption results show that the presence of the active component NiO plays an important role in improving the CO_(2) adsorption performance,and the NiO@USY composite with a NiO loading of 1.5 mmol·g^(-1) USY support displays a high adsorption capacity and adsorption selectivity for CO_(2),and shows a good cycle stability.In addition,the Clausius–Clapeyron equation was used to evaluate the isosteric heat of adsorption of CO_(2) on the NiO(1.5)@USY composite,and the heat of adsorption was 17.39–38.34 kJ·mol^(-1).
基金supported by the National Natural Science Foundation of China(No.20877036).
文摘The surface ion-imprinting concept and chitosan incorporated sol-gel process were applied to the synthesis of a new attapulgitesupported polymer for selective separation of Ce(III) from aqueous solution. The imprinting mechanism of prepared ion-imprinted polymer were discussed with the Characteristics of FT-IR and SEM. Results from the experiments of adsorption capacity and selectivity suggested that ion-imprinted polymer offered a fast kinetics for the adsorption of Ce(III) under the optimum conditions. Its maximum adsorption capacity was 38.02 mg/g, and the selective recognition towards Ce(III) was much higher than that of the non-imprinted polymer and attapulgite. The prepared functional polymer was shown to be promising for selective separation and enrichment of trace Ce(III) in environmental samples. ?2009 Yong Sheng Yan. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
基金This work was supported by the National Natural Science Foundation of China(Nos.42077114 and 41771346)the Local Innovation and Entrepreneurship Team Project of Guangdong Special Support Program(No.2019BT02L218)Zhaoqing University Innovation Research Team Funding Project.
文摘Surfactant enhanced elution is an effective method for removing hydrophobic organic pollutants from soils.The key to the development of leaching technology is selective removal of targeted pollutants in soil washing effluent and recycling of surfactant solutions.In this study,a molecular imprinting technique was applied to selectively sorb polybrominated diphenyl ethers(PBDEs)in soil washing effluent.The novel molecular imprinted polymers(MIPs)using different template molecules were synthesized by precipitation polymerization.Adsorption behaviors andmechanisms ofMIPs were studied through experiments and theoretical calculations.The results show that 4-bromo-4'-hydroxybiphenyl and toluene can be effective imprinting molecule for MIPs synthesis.The maximal adsorption capacity of selected dummy molecular imprinted polymer(D1-MIP)was 1032.36μmol/g,and that of part molecular imprinted polymer(P-MIP)was 981.13μmol/g.Their imprinting factors in 5 PBDEs adsorption ranged from 2.13 to 5.88,the recovery percentage of Triton X-100 can reach 99.09%,confirming the feasibility of reusing surfactant.Various PBDEs could be removed by MIPs,and Quantitative Structure Property Relationship analysis revealed that PBDEs’molecular volume,planarity,polarity,and hydrophobicity have major influences on their adsorption performance.DFT calculation revealed that Van derWaals force and hydrogen bonding played important roles during selective adsorption.These results can provide effective theoretical guidance for surfactant enhanced soil elution in practical engineering applications.
基金supported by the Interdisciplinary Project of the Nanjing Normal University (No.164320H1847)the National Natural Science Foundation of China (No.41772360)。
文摘The development of bio-adsorbents with highly selective immobilization properties for specific heavy metals is a great challenge,but has important application value.Biogenic whewellite(BW)with high selectivity for Pb(Ⅱ)was synthesized by mineral microbial transformation.The selective immobilization properties and mechanism of BW for Pb(Ⅱ)were analyzed by combining mineral characterization technology and batch adsorption research methods.The results indicated that BW can efficiently and selectively immobilize Pb(Ⅱ)in single or composite heavy metal adsorption solutions,and the immobilized Pb(Ⅱ)is difficult to desorb.BW undergoes monolayer adsorption on Pb(Ⅱ),Qmax≈1073.17 mg/g.The immobilization of Pb(Ⅱ)by BW is a physico-chemical adsorption process with spontaneous heat absorption and an accompanying increase in entropy.In addition,the sequestration of Pb(Ⅱ)by BW remains around 756.99 mg/g even at p H=1.The excellent selective immobilization properties of BW for Pb(Ⅱ)are closely related to its smaller Ksp,electrostatic repulsion effect,organic-inorganic composite structure,acid resistance and the formation of Pb(Ⅱ)oxalate.This study provides beneficial information about the recycling of lead in acidic lead-containing wastewater and composite heavy metal contaminated water bodies.
基金supported by the National Natural Science Foundation of China(Grant Nos.52106241,52276189 and 52006069)Fundamental Research Funds for the Central Universities(Grant Nos.2023JC009 and 2022YQ002).
文摘The composition of biomass pyrolysis gas is complex,and the selective separation of its components is crucial for its further utilization.Metal-incorporated nitrogen-doped materials exhibit enormous potential,whereas the relevant adsorption mechanism is still unclear.Herein,16 metal-incorporated nitrogen-doped carbon materials were designed based on the density functional theory calculation,and the adsorption mechanism of pyrolysis gas components H2,CO,CO_(2),CH_(4),and C2H6 was explored.The results indicate that metal-incorporated nitrogen-doped carbon materials generally have better adsorption effects on CO and CO_(2)than on H_(2),CH_(4),and C_(2)H_(6).Transition metal Mo-and alkaline earth metal Mg-and Ca-incorporated nitrogen-doped carbon materials show the potential to separate CO and CO_(2).The mixed adsorption results of CO_(2)and CO further indicate that when the CO_(2)ratio is significantly higher than that of CO,the saturated adsorption of CO_(2)will precede that of CO.Overall,the three metal-incorporated nitrogen-doped carbon materials can selectively separate CO_(2),and the alkaline earth metal Mg-incorporated nitrogen-doped carbon material has the best performance.This study provides theoretical guidance for the design of carbon capture materials and lays the foundation for the efficient utilization of biomass pyrolysis gas.
文摘A novel Ni(Ⅱ) ion-imprinted silica gel polymer was prepared via the surface imprinting technique combined with aqueous solution polymerization by using 2-acrylamido-2-methyl-1-propanesulfonic acid(AMPS) as a functional monomer for the selective separation of Ni(Ⅱ) from aqueous solution. The sorbent showed good chemical and thermal stability. Kinetics studies indicated that the equilibrium adsorption was achieved within 10 min and the adsorption kinetics fitted well with the pseudo-second-order kinetic model. The maximum adsorption capacity of the ion-imprinted polymer towards Ni(Ⅱ) at the optimal p H of 7.0 was 66.22 mg·g^(-1). The relative selectivity coefficients of the sorbent were 9.23, 15.71, 14.72 and 20.15 for Ni(Ⅱ)/Co(Ⅱ), Ni(Ⅱ)/Cu(Ⅱ), Ni(Ⅱ)/Zn(Ⅱ) and Ni(Ⅱ)/Pb(Ⅱ), respectively. The adsorption isotherm fitted well with Langmuir isotherm model. The thermodynamic results indicated that the adsorption of Ni(Ⅱ) was a spontaneous and endothermic process. The sorbent showed good reusability evidenced by six cycles of adsorption/desorption experiments. The precision of this method is satisfactory. Thus, the prepared sorbent can be considered as a promising sorbent for selective separation of Ni(Ⅱ) in real water samples.
基金supported by the National Natural Science Foundation of China(No.21971207)。
文摘A multi-site functionalized microporous metal-organic framework(MOF),H[Zn2(BDP)0.5(ATZ)3]·0.5 H_(2)O·0.5DMF(1),was synthesized through mixed ligands strategy.The pore surface of complex 1 was modified by uncoordinated carboxylate O atoms,phenyl and pyridyl rings as well as-NH_(2) groups,which strengthen interactions with C2H6,C_(2)H_(4) and CO_(2) molecules and lead to efficiently selective C2H6,C_(2)H_(4) and CO_(2) uptake over CH_(4).The selective adsorption mechanism was discussed deeply based on Grand Canonical Monte Carlo(GCMC)simulations.It is expected that this study will provide a new perspective for the rational design and synthesis of MOFs with efficient gas adsorption and separation performance.
基金supported by the National Natural Science Foundation of China(Nos.21773041,and 21972031)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB36000000)+1 种基金the Natural Science Foundation of Zhejiang Province(No.Y20B020032)China Scholarship Council(No.202007090155).
文摘The prediction of two-dimensional molecular self-assembly structures has always been a problem to be solved.The molecules with meta-dicarboxyl groups can self-assemble into a specific hexagonal cavity,which has an important influence on the prediction of molecular self-assembly structures and the application of functional molecules with meta-dicarboxyl groups.Two kinds of molecules with four pairs of meta-dicarboxyl groups,1,3,6,8-tet「akis(3,5-isophthalic acid)pyrene(H_(8)TIAPy)and 4′,4′",4′"",4""-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1′-biphenyl]-3,5-dicarboxylic acid))(H8ETTB)molecules were chosen to observe the self-assembly behavior at the heptanoic acid/highly oriented pyrolytic graphite(HA/HOPG)interface.H8TIAPy molecules self-assembled into well-ordered quadrilateral structures and could be regulated into kagome networks with hexagonal pores by coronene(COR)molecules.H8ETTB molecules self-assembled into lamellar structures and transformed into acid-COR-acid-COR co-assembled structures at low concentration of COR solution and acid-COR dimer-acid-COR dimer co-assembled structures at high concentration of COR solution.The reason that H8ETTB molecules could not be regulated into hexagonal porous architecture was attributed to the steric hindrance by the similar length and width of H8ETTB molecules.The H8ETTB templates had stronger adsorption for COR than that of hexaphenylbenzene(HPB),regardless of the order of molecular introduction.