Ionic liquids as green solvents have shown important application in the extraction and separation of nonferrous metals.The new application perspective,the important fundamental and the applied studies of the extractio...Ionic liquids as green solvents have shown important application in the extraction and separation of nonferrous metals.The new application perspective,the important fundamental and the applied studies of the extraction and separation of nonferrous metals in ionic liquids,including the dissolution and corrosion of metal and metal oxide,hydrometallurgy of chalcopyrite and metallic oxidized ore,and extraction and separation of metal ions,are introduced.展开更多
Nano-assisted inclusion separation of alkali metals from basic solutions was reported by inclu sion-facilitated emulsion liquid membrane process. The novelty of this study is application of nano-baskets of calixcrown ...Nano-assisted inclusion separation of alkali metals from basic solutions was reported by inclu sion-facilitated emulsion liquid membrane process. The novelty of this study is application of nano-baskets of calixcrown in the selective and efficient separation of alkali metals as both the carrier and the surfactant. For this aim, four derivatives of diacid calix[4]-1,3-crowns-4,5 were synthesized, and their inclusion-extraction parameters were optimized including the calixcrown scaffold (4.4%, by mass) as the carrier/demulsifier, the commercial kero sene as diluent in membrane, sulphonic acid (0.2 mol.L-1) and ammonium carbonate (0.4 mol.L-1) as the strip and the feed phases, the phase and the treat ratios of 0.8 and 0.3, mixing speed (300 r.min-1), and initial solute concentration (100 mg.L-1). The selectivity of membrane over more than ten interfering cations was examined and the re sults reveled that under the optimized operating condition, the degree of inclusion-extraction of alkali metals was as high as 98%-99%.展开更多
1-butyl-3-methylimidazolium perchlorate([BMIM]ClO4) was synthesized by two steps with N-methylimidazolium.Some physico-chemical properties,such as density,surface tension,viscosity,electrical conductivity as well as e...1-butyl-3-methylimidazolium perchlorate([BMIM]ClO4) was synthesized by two steps with N-methylimidazolium.Some physico-chemical properties,such as density,surface tension,viscosity,electrical conductivity as well as electrochemical window,were investigated and solvent performance was also studied.The results show that this kind of ionic liquid is an excellent electrolyte with low viscosity,high electrical conductivity and wide electrochemical window.In addition,[BMIM]ClO4 is soluble in most conventional solvents and some metal oxides have high solubility in it,which lays the foundation of direct electrolysis of metal oxides in this ionic liquid.展开更多
To investigate effect of metallic ion activation on different particle sizes of quartz in butyl xanthate solution,six common ions(Pb^(2+),Cu^(2+),Fe^(3+),Fe^(2+),Mg^(2+) and Ca^(2+)) were introduced as activators.The ...To investigate effect of metallic ion activation on different particle sizes of quartz in butyl xanthate solution,six common ions(Pb^(2+),Cu^(2+),Fe^(3+),Fe^(2+),Mg^(2+) and Ca^(2+)) were introduced as activators.The approaches of micro-flotation,adsorption test and zeta potential measurement were adopted to reveal the mechanism of ion activation.The results show that Pb^(2+),Cu^(2+) and Fe^(3+) are effective activators for the flotation of quartz in butyl xanthate solution because of their absorption on activated quartz surface.Average recoveries of fine particles(<37 μm) are greater than those of coarser particles(37-74 μm),suggesting that the former is easier to be activated and more likely to be floated and thus entrained in sulphide concentrate.From another perspective,addition of metallic ions(Pb^(2+),Cu^(2+) and Fe^(3+)) renders zeta potentials move positively,and addition of the same metallic ions and butyl xanthate makes zeta potential drop apparently,which support a mechanism where they adsorb onto quartz surface,resulting in an expected increase in butyl xanthate collector adsorption with a concomitant increase in the flotation recoveries.展开更多
The effects of components and their ratio of grouts on anti-seepage capability of clay-solidified grouting curtain and its permeability of heavy metal cations were investigated by permeating experiments, using reactiv...The effects of components and their ratio of grouts on anti-seepage capability of clay-solidified grouting curtain and its permeability of heavy metal cations were investigated by permeating experiments, using reactive solute transport model to study the permeation of heavy metals (Cd2+, Pb2+ and Hg2+). The study of permeating for different mixture ratios of cement and clay indicates that hydraulic conductivity of clay-solidified grouting curtain with different ratios of solid to liquid or with the same ratio of solid to liquid but with different ratios of cement to clay is changed. The laboratory simulation test results also show that precipitates produced in heavy metal cation migration process in curtain block up water flowing passage which makes the hydraulic conductivity of the solution-permeated curtain decrease with the leakage time. The permeation velocities for different heavy metal cations vary with ionic concentration, exchange capacity and ion radius etc. The test results indicate that the permeation rapidity order of heavy metals cations in clay-solidified grouting curtain is Hg2+>Pb2+ in the same experimental circumstance. In addition, permeability for different mixture ratios and antisepsis capabilities of clay-solidified grouting curtain were studied in tests.展开更多
The industrial silica fume pretreated by nitric acid at 80 °C was re-used in this work. Then, the obtained silica nanoparticles were surface functionalized by silane coupling agents, such as(3-Mercaptopropyl) tri...The industrial silica fume pretreated by nitric acid at 80 °C was re-used in this work. Then, the obtained silica nanoparticles were surface functionalized by silane coupling agents, such as(3-Mercaptopropyl) triethoxysilane(MPTES) and(3-Amincpropyl) trithoxysilane(APTES). Some further modifications were studied by chloroaceetyl choride and 1,8-Diaminoaphalene for amino modified silica. The surface functionalized silica nanoparticles were characterized by Fourier transform infrared(FI-IR) and X-ray photoelectron spectroscopy(XPS). The prepared adsorbent of surface functionalized silica nanoparticles with differential function groups were investigated in the selective adsorption about Pb2+, Cu2+, Hg2+, Cd2+ and Zn2+ions in aqueous solutions. The results show that the(3-Mercaptopropyl) triethoxysilane functionalized silica nanoparticles(SiO2-MPTES) play an important role in the selective adsorption of Cu2+ and Hg2+, the(3-Amincpropyl) trithoxysilane(APTES) functionalized silica nanoparticles(SiO2-APTES) exhibited maximum removal efficiency towards Pb2+ and Hg2+, the 1,8-Diaminoaphalene functionalized silica nanoparticles was excellent for removal of Hg2+ at room temperature, respectively.展开更多
The electrochemical reduction of CO_(2) towards hydrocarbons is a promising technology that can utilize CO_(2) and prevent its atmospheric accumulation while simultaneously storing renewable en‐ergy.However,current C...The electrochemical reduction of CO_(2) towards hydrocarbons is a promising technology that can utilize CO_(2) and prevent its atmospheric accumulation while simultaneously storing renewable en‐ergy.However,current CO_(2) electrolyzers remain impractical on a large scale due to the low current densities and faradaic efficiencies(FE)on various electrocatalysts.In this study,hybrid HKUST‐1 metal‐organic framework‒fluorinated imidazolium‐based room temperature ionic liquid(RTIL)electrocatalysts are designed to selectively reduce CO_(2) to CH_(4).An impressive FE of 65.5%towards CH_(4) at-1.13 V is achieved for the HKUST‐1/[BMIM][PF_(6)]hybrid,with a stable FE greater than 50%maintained for at least 9 h in an H‐cell.The observed improvements are attributed to the increased local CO_(2) concentration and the improved CO_(2)‐to‐CH_(4) thermodynamics in the presence of the RTIL molecules adsorbed on the HKUST‐1‐derived Cu clusters.These findings offer a novel approach of immobilizing RTIL co‐catalysts within porous frameworks for CO_(2) electroreduction applications.展开更多
In this paper, we report on the comprehensive alcohol-/ion-responsive properties of a smart copolymer poly(N- isopropylacry]amide-co-benzo-18-crown-6-acrylamide) (P(NIPAM-co-BCAm)). The orthogonal design method ...In this paper, we report on the comprehensive alcohol-/ion-responsive properties of a smart copolymer poly(N- isopropylacry]amide-co-benzo-18-crown-6-acrylamide) (P(NIPAM-co-BCAm)). The orthogonal design method is adopted for experimental design. The experimental results show that alcohol can trigger the shrinking and Ba2t can induce the swelling of the P(NIPAM-co-BCAm) copolymer. According to the phase transition tempera- ture (LCST) change results of the copolymer, the influence of variables on the LCST changes weakens in the following order: alcohol concentration 〉 alcohol species 〉 metal ion species 〉 BCAm concentration 〉 ion concentration. The larger the alcohol concentration and the larger the molecular size of alcohols, the lower the LCST value; on the contrary, the more the BCAm content in the copolymer or the larger the BCAm/ion complex stability constant (IgK) or the larger the ion concentration is, the higher the LCST value. For a P(NIPAM-co-BCAm ) copolymer with a fixed BCAm content, a binary function of ion concentration and IgK of BCAm/ion is developed to precisely predict the LCST values of the copolymer in different metal ion solutions. The results provide valuable information for fabricating artificial biomimetic G-protein-gated inwardly rectifying potassium (GIRK) channels that are activated by alcohol and inhibited by Ba2+.展开更多
In this study, the feasibility of using chitosan, a multifunctional environmentally friendly biopolymer, at different molecular weights to simultaneously adsorb various metal ions from aqueous solutions was evaluated....In this study, the feasibility of using chitosan, a multifunctional environmentally friendly biopolymer, at different molecular weights to simultaneously adsorb various metal ions from aqueous solutions was evaluated. The experiments were carried out to estimate adsorptivity and selectivity of three molecular weights chitosan, 3.60 × 105 (Chl), 5.97 × 105 (Ch2) and 9.47 × 105 (Ch3) g/mol, towards Cu(II), Ni(II), and Pb(II) ions in aqueous solutions. Experimental results indicated that chitosan of high molecular weight (Ch3) was the best at adsorption capacity than the others. On chitosan solutions followed by Ni(II) and then Cu(II). the other hand, Pb(lI) had the highest adsorption ability in the three展开更多
Add the masking agent and biscyclohexanoneoxalyldihydraone into the diluted clarificd liquid of the landfill leachate which was treatmented by digestion and centrifugal filtration to complexate all heavy metal ion in ...Add the masking agent and biscyclohexanoneoxalyldihydraone into the diluted clarificd liquid of the landfill leachate which was treatmented by digestion and centrifugal filtration to complexate all heavy metal ion in the trcatmented liquid, and extracted using CHCl3 many time, then it were demasking and decomposing respectively, and adjusted different pH and formed Me^n+-PAN coordination compound when these metal ion reaction with PAN. The Fluoresence quenching of Rh6G (λex/λem=543mn/558nm) when the metal ion coordination compound was add into the Rh6G solution step by step, the quenching intensity was directly proportional to the concentration of the metal ion in the certain range. So a new method of fast and simple for determination of trace metal ion in landfill lcachate was established to determine metal ion in sample of different landfill leachate in Three Gorge Water Reservoir, and comparison the classic assay method with satisfactory results.展开更多
Tin dioxide (SnO2) has attracted broad interest due to its particular gas-sensor property. Nano- or atom-scale SnO2 material has always been the aim in order to ultimately improve the sensitivity. However, until now, ...Tin dioxide (SnO2) has attracted broad interest due to its particular gas-sensor property. Nano- or atom-scale SnO2 material has always been the aim in order to ultimately improve the sensitivity. However, until now, it remains difficult to synthesize SnO2 nanoclusters by using traditional methods. In the present work, we have achieved the preparation of SnO2 nanoclusters by using the cluster beam deposition technique. The obtained nanoclusters were well characterized by high resolution transmission electron microscope HR-TEM. Results indicated the formation of the well-dispersed SnO2 nanoclusters with uniform size distribution (5-7 nm). Furthermore, an obvious metal insulator transition was observed by gating with ionic liquid. Combined with theory calculation, the corresponding mechanism was systematically analyzed from oxygen vacancy induced electron doping.展开更多
The uniform surface ion-imprinted resins for Zn2+ as the imprinting guest were prepared by emulsifier-free emulsion polymerization utilizing ally phenyl hydrogenphosphate as a functional comonomer. The Zn2+-imprinted ...The uniform surface ion-imprinted resins for Zn2+ as the imprinting guest were prepared by emulsifier-free emulsion polymerization utilizing ally phenyl hydrogenphosphate as a functional comonomer. The Zn2+-imprinted resin adsorbed Zn2+ much more effectively than did the unimprinted one. The selective feature of the surface imprinted resins to the template ions was demonstrated.展开更多
This paper studies the reaction between alkaline metal ions Li+, Na+ and K+ and ASR (alkali-silica reaction) reactive aggregates to determine whether Li+ can substitute Na+ and K+ that are unified in cement pa...This paper studies the reaction between alkaline metal ions Li+, Na+ and K+ and ASR (alkali-silica reaction) reactive aggregates to determine whether Li+ can substitute Na+ and K+ that are unified in cement paste. Reactive aggregates use meta-sandstone from eastern Taiwan and Pyrex glass. Non-reactive aggregates use siliceous sand. The results show that the dissolved amount of SiO2 is lower when the reactive aggregates are immersed in an 80 ℃1 N LiOH'H20 solution than in NaOH and KOH solutions. The reduced amounts of OH and Li+ in the solution are also higher than those in the NaOH and KOH solutions. These results reveal that reactive SiO2 can react with LiOH to form a reactant with low water solubility. When the powder of the cement paste is immersed in an 80 ℃ 1 N LiOH-H2O solution, the amounts of free Na+ and K+ in the solution are higher than those in water. The increased amount increases with the duration of immersion. The amount of Li+ in the solution also decreases with the duration of immersion. These results reveal that Li+ can substitute Na+ and K+ that are unified in cement paste, which indicates that ASR can be prevented with the existence of Li+.展开更多
Toxic Zn(II) ion imprinted interpenetrating polymer networks were synthesized for the selective sorption of Zn(ll) from aqueous solutions using a biopolymer alginic acid. The polymeric biosorbant was prepared usin...Toxic Zn(II) ion imprinted interpenetrating polymer networks were synthesized for the selective sorption of Zn(ll) from aqueous solutions using a biopolymer alginic acid. The polymeric biosorbant was prepared using Zn(II) ion as template, acrylamide as functional monomer, cross linker NNMBA (N,N' Methylene-bis-acrylamide) and potassium persulphate as an initiator. The non-imprinted polymer networks were also prepared without use of the Zn(II) ion. The synthesized interpenetrating networks were characterized by various spectral techniques. Metal ion binding studies were carried out and the factors affecting binding were also optimized. Competitive sorption studies were investigated to determine the selectivity of Zn(II) ion imprinted interpenetrating polymer network. Zinc ion imprinted polymer networks showed good selectivity for the target ion.展开更多
The electrochemical behavior of Al(Ⅲ)in urea-1-butyl-3-methylimidazolium chloride-aluminum chloride(urea-BMIC-AlCl_(3))ionic liquids,and the effect of potential and temperature on the characterization of cathode prod...The electrochemical behavior of Al(Ⅲ)in urea-1-butyl-3-methylimidazolium chloride-aluminum chloride(urea-BMIC-AlCl_(3))ionic liquids,and the effect of potential and temperature on the characterization of cathode products,current efficiency and energy consumption of aluminum electrorefining have been investigated.Cyclic voltammetry showed that the electrochemical reduction of Al(Ⅲ)was a one-step three-electron-transfer irreversible reaction,and the electrochemical reaction was controlled by diffusion.The diffusion coefficient of Al(Ⅲ)in urea-BMIC-AlCl_(3)ionic liquids at 313 K was 1.94×10^(−7)cm^(2)/s.The 7075 aluminum alloy was used as an anode for electrorefining,and the cathode products were analyzed by XRD,SEM and EDS.The results from XRD analysis indicated that the main phase of the cathode products was aluminum.The results from SEM and EDS characterization revealed that the cathode product obtained by electrorefining−1.2 V(vs.Al)was dense and uniform,and the mass fraction of aluminum decreased from 99.61%to 99.10%as the experimental temperature increased from 313 K to 333 K.In this work,the optimum experimental conditions were−1.2 V(vs.Al)and 313 K.At this time,the cathode current efficiency was 97.80%,while the energy consumption was 3.72 kW·h/kg.展开更多
Cerium-doped zirconium-based NH_(2)-UiO-66 nanoparticles were synthesized in ionic liquid 1-butyl-3-methylimidazolium acetate at room temperature.The crystal structure and morphology were studied using X-ray diffracti...Cerium-doped zirconium-based NH_(2)-UiO-66 nanoparticles were synthesized in ionic liquid 1-butyl-3-methylimidazolium acetate at room temperature.The crystal structure and morphology were studied using X-ray diffraction,infrared spectroscopy,scanning electron microscopy and transmission electron microscopy.The valence state and distribution of elements in the obtained materials were examined using X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy.Catalytic performance studies show that the cerium-doped NH_(2)-UiO-66 exhibits improved catalytic efficiency in the cycloaddition reaction of 1,2-butylene oxide and carbon dioxide than pure NH_(2)-UiO-66.Studies on the photoelectric properties indicate that the cerium-doped NH_(2)-UiO-66 catalyst possesses strong photocurrent response,low interfacial charge transfer resistance,narrow band gap,and low flat band potential.This work provides a new approach of synthesizing high-performance catalyst for photocatalytic CO_(2) cycloaddition.展开更多
This review summarizes the preparation methods of support ionic liquids (SILs) and their applications in rare metals separation The rare metals separation includes the recovery of high value metal ions and the remov...This review summarizes the preparation methods of support ionic liquids (SILs) and their applications in rare metals separation The rare metals separation includes the recovery of high value metal ions and the removal of heavy metal ions from wastewater. SILs can be used as a kind of highly efficient multifunctional separation materials. The preparation methods of SILs include chemical immobilization technique in which ILs moieties are supported on solid supports via covalent bonds and physical immobilization techniques in which ILs are immobilized on solid supports via physical method such as simple im- pregnation, sol-gel method. According to the difference of solid supports, this review summarizes the application of polymer supported ionic liquids (P-SILs), silica based material supported ionic liquids (SM-SILs) and membrane supported ionic liq- uids (M-SILs) in rare metals separation, P-SILs and SM-SILs prepared by chemical method with N-methylimidazolium group can be used as highly efficient anion exchangers with high thermal stability and good chemical stability for adsorption of Cr(Ⅵ), Re(Ⅶ), Ce(Ⅳ). P-SILs prepared via simple impregnation afforded IL functionalized solvent impregnated resins (SIRs) which showed high separation efficiency and selectivity in the separation of rare earths(Ⅲ) (REs(Ⅲ)). SM-SILs prepared via sol-gel method with IL doped in the support as porogens or extractant show high removal efficiencies and excellent stability for the separation of RE(Ⅲ), Cr(Ⅲ) and Cr(Ⅵ). M-SILs with IL as plasticizer or carrier show improved stability, high perme- ability coefficient and good selectivity for Cr(VI) transport. Different supports and different supporting methods were suffi- ciently compared. Based on the different practical application, different forms of SILs can be prepared for separation of rare metals with high separation efficiency and selectivity.展开更多
Polyoxometalates(POMs) are a class of molecular metal oxides, showing numerous applications in various chemical processes due to their unique acid/base and redox features. By adjusting the tunable molecular structures...Polyoxometalates(POMs) are a class of molecular metal oxides, showing numerous applications in various chemical processes due to their unique acid/base and redox features. By adjusting the tunable molecular structures of the anions and counter cations, plenty of POM-based ionic liquids(POM-based ILs) have been fabricated to be used in various fields, such as catalysis, structural chemistry and material science. As a class of excellent catalysts, POM-based ILs have shown advantages in the emerging field of CO_2 utilization such as CO_2 capture, cycloaddition of CO_2 to epoxides, and reduction of CO_2, owing to the efficient activation of CO_2 by POM anions. This review summarizes recent advances in the catalysis of POM-based ILs, and particularly highlights the areas that are related to CO_2 conversion.展开更多
基金Project(50904031) supported by the National Natural Science Foundation of ChinaProject(2008E0049M) supported by the Natural Science Foundation of Yunnan Province,China+1 种基金Project(07Z40082) supported by the Science Foundation of the Education Department of Yunnan Province,ChinaProject(2007-16) supported by the Science Foundation of Kunming University of Science and Technology,China
文摘Ionic liquids as green solvents have shown important application in the extraction and separation of nonferrous metals.The new application perspective,the important fundamental and the applied studies of the extraction and separation of nonferrous metals in ionic liquids,including the dissolution and corrosion of metal and metal oxide,hydrometallurgy of chalcopyrite and metallic oxidized ore,and extraction and separation of metal ions,are introduced.
基金supported by Islamic Azad University (Shahreza Branch)Iran Nanotechnology Initiative Council
文摘Nano-assisted inclusion separation of alkali metals from basic solutions was reported by inclu sion-facilitated emulsion liquid membrane process. The novelty of this study is application of nano-baskets of calixcrown in the selective and efficient separation of alkali metals as both the carrier and the surfactant. For this aim, four derivatives of diacid calix[4]-1,3-crowns-4,5 were synthesized, and their inclusion-extraction parameters were optimized including the calixcrown scaffold (4.4%, by mass) as the carrier/demulsifier, the commercial kero sene as diluent in membrane, sulphonic acid (0.2 mol.L-1) and ammonium carbonate (0.4 mol.L-1) as the strip and the feed phases, the phase and the treat ratios of 0.8 and 0.3, mixing speed (300 r.min-1), and initial solute concentration (100 mg.L-1). The selectivity of membrane over more than ten interfering cations was examined and the re sults reveled that under the optimized operating condition, the degree of inclusion-extraction of alkali metals was as high as 98%-99%.
基金Project(50574031) supported by the National Natural Science Foundation of China
文摘1-butyl-3-methylimidazolium perchlorate([BMIM]ClO4) was synthesized by two steps with N-methylimidazolium.Some physico-chemical properties,such as density,surface tension,viscosity,electrical conductivity as well as electrochemical window,were investigated and solvent performance was also studied.The results show that this kind of ionic liquid is an excellent electrolyte with low viscosity,high electrical conductivity and wide electrochemical window.In addition,[BMIM]ClO4 is soluble in most conventional solvents and some metal oxides have high solubility in it,which lays the foundation of direct electrolysis of metal oxides in this ionic liquid.
基金Project(51274255)supported by the National Natural Science Foundation of ChinaProject(2015CX005)supported by Innovation Driven Plan of Central South University,China+1 种基金Project(2016RS2016)supported by Hunan Provincial Science and Technology Leader(Innovation Team of Interface Chemistry of Efficient and Clean Utilization of Complex Mineral Resources),ChinaProject supported by the Postdoctoral Research Station of Central South University,China
文摘To investigate effect of metallic ion activation on different particle sizes of quartz in butyl xanthate solution,six common ions(Pb^(2+),Cu^(2+),Fe^(3+),Fe^(2+),Mg^(2+) and Ca^(2+)) were introduced as activators.The approaches of micro-flotation,adsorption test and zeta potential measurement were adopted to reveal the mechanism of ion activation.The results show that Pb^(2+),Cu^(2+) and Fe^(3+) are effective activators for the flotation of quartz in butyl xanthate solution because of their absorption on activated quartz surface.Average recoveries of fine particles(<37 μm) are greater than those of coarser particles(37-74 μm),suggesting that the former is easier to be activated and more likely to be floated and thus entrained in sulphide concentrate.From another perspective,addition of metallic ions(Pb^(2+),Cu^(2+) and Fe^(3+)) renders zeta potentials move positively,and addition of the same metallic ions and butyl xanthate makes zeta potential drop apparently,which support a mechanism where they adsorb onto quartz surface,resulting in an expected increase in butyl xanthate collector adsorption with a concomitant increase in the flotation recoveries.
文摘The effects of components and their ratio of grouts on anti-seepage capability of clay-solidified grouting curtain and its permeability of heavy metal cations were investigated by permeating experiments, using reactive solute transport model to study the permeation of heavy metals (Cd2+, Pb2+ and Hg2+). The study of permeating for different mixture ratios of cement and clay indicates that hydraulic conductivity of clay-solidified grouting curtain with different ratios of solid to liquid or with the same ratio of solid to liquid but with different ratios of cement to clay is changed. The laboratory simulation test results also show that precipitates produced in heavy metal cation migration process in curtain block up water flowing passage which makes the hydraulic conductivity of the solution-permeated curtain decrease with the leakage time. The permeation velocities for different heavy metal cations vary with ionic concentration, exchange capacity and ion radius etc. The test results indicate that the permeation rapidity order of heavy metals cations in clay-solidified grouting curtain is Hg2+>Pb2+ in the same experimental circumstance. In addition, permeability for different mixture ratios and antisepsis capabilities of clay-solidified grouting curtain were studied in tests.
基金Project(2012CB722803)supported by the Key Project of National Basic Research and Development Program of ChinaProject(U1202271)supported by the National Natural Science Foundation of ChinaProject(IRT1250)supported by the Program for Innovative Research Team in University of Ministry of Education of China
文摘The industrial silica fume pretreated by nitric acid at 80 °C was re-used in this work. Then, the obtained silica nanoparticles were surface functionalized by silane coupling agents, such as(3-Mercaptopropyl) triethoxysilane(MPTES) and(3-Amincpropyl) trithoxysilane(APTES). Some further modifications were studied by chloroaceetyl choride and 1,8-Diaminoaphalene for amino modified silica. The surface functionalized silica nanoparticles were characterized by Fourier transform infrared(FI-IR) and X-ray photoelectron spectroscopy(XPS). The prepared adsorbent of surface functionalized silica nanoparticles with differential function groups were investigated in the selective adsorption about Pb2+, Cu2+, Hg2+, Cd2+ and Zn2+ions in aqueous solutions. The results show that the(3-Mercaptopropyl) triethoxysilane functionalized silica nanoparticles(SiO2-MPTES) play an important role in the selective adsorption of Cu2+ and Hg2+, the(3-Amincpropyl) trithoxysilane(APTES) functionalized silica nanoparticles(SiO2-APTES) exhibited maximum removal efficiency towards Pb2+ and Hg2+, the 1,8-Diaminoaphalene functionalized silica nanoparticles was excellent for removal of Hg2+ at room temperature, respectively.
文摘The electrochemical reduction of CO_(2) towards hydrocarbons is a promising technology that can utilize CO_(2) and prevent its atmospheric accumulation while simultaneously storing renewable en‐ergy.However,current CO_(2) electrolyzers remain impractical on a large scale due to the low current densities and faradaic efficiencies(FE)on various electrocatalysts.In this study,hybrid HKUST‐1 metal‐organic framework‒fluorinated imidazolium‐based room temperature ionic liquid(RTIL)electrocatalysts are designed to selectively reduce CO_(2) to CH_(4).An impressive FE of 65.5%towards CH_(4) at-1.13 V is achieved for the HKUST‐1/[BMIM][PF_(6)]hybrid,with a stable FE greater than 50%maintained for at least 9 h in an H‐cell.The observed improvements are attributed to the increased local CO_(2) concentration and the improved CO_(2)‐to‐CH_(4) thermodynamics in the presence of the RTIL molecules adsorbed on the HKUST‐1‐derived Cu clusters.These findings offer a novel approach of immobilizing RTIL co‐catalysts within porous frameworks for CO_(2) electroreduction applications.
基金Supported by the National Natural Science Foundation of China(21136006)the Foundation for the Author of National Excellent Doctoral Dissertation of PR China(201163)the National High Technology Research and Development Program(2012AA021403)
文摘In this paper, we report on the comprehensive alcohol-/ion-responsive properties of a smart copolymer poly(N- isopropylacry]amide-co-benzo-18-crown-6-acrylamide) (P(NIPAM-co-BCAm)). The orthogonal design method is adopted for experimental design. The experimental results show that alcohol can trigger the shrinking and Ba2t can induce the swelling of the P(NIPAM-co-BCAm) copolymer. According to the phase transition tempera- ture (LCST) change results of the copolymer, the influence of variables on the LCST changes weakens in the following order: alcohol concentration 〉 alcohol species 〉 metal ion species 〉 BCAm concentration 〉 ion concentration. The larger the alcohol concentration and the larger the molecular size of alcohols, the lower the LCST value; on the contrary, the more the BCAm content in the copolymer or the larger the BCAm/ion complex stability constant (IgK) or the larger the ion concentration is, the higher the LCST value. For a P(NIPAM-co-BCAm ) copolymer with a fixed BCAm content, a binary function of ion concentration and IgK of BCAm/ion is developed to precisely predict the LCST values of the copolymer in different metal ion solutions. The results provide valuable information for fabricating artificial biomimetic G-protein-gated inwardly rectifying potassium (GIRK) channels that are activated by alcohol and inhibited by Ba2+.
文摘In this study, the feasibility of using chitosan, a multifunctional environmentally friendly biopolymer, at different molecular weights to simultaneously adsorb various metal ions from aqueous solutions was evaluated. The experiments were carried out to estimate adsorptivity and selectivity of three molecular weights chitosan, 3.60 × 105 (Chl), 5.97 × 105 (Ch2) and 9.47 × 105 (Ch3) g/mol, towards Cu(II), Ni(II), and Pb(II) ions in aqueous solutions. Experimental results indicated that chitosan of high molecular weight (Ch3) was the best at adsorption capacity than the others. On chitosan solutions followed by Ni(II) and then Cu(II). the other hand, Pb(lI) had the highest adsorption ability in the three
文摘Add the masking agent and biscyclohexanoneoxalyldihydraone into the diluted clarificd liquid of the landfill leachate which was treatmented by digestion and centrifugal filtration to complexate all heavy metal ion in the trcatmented liquid, and extracted using CHCl3 many time, then it were demasking and decomposing respectively, and adjusted different pH and formed Me^n+-PAN coordination compound when these metal ion reaction with PAN. The Fluoresence quenching of Rh6G (λex/λem=543mn/558nm) when the metal ion coordination compound was add into the Rh6G solution step by step, the quenching intensity was directly proportional to the concentration of the metal ion in the certain range. So a new method of fast and simple for determination of trace metal ion in landfill lcachate was established to determine metal ion in sample of different landfill leachate in Three Gorge Water Reservoir, and comparison the classic assay method with satisfactory results.
基金supported by the National Natural Science Foundation of China(No.11704325,No.11604288,and No.11774178)the Natural Science Foundation of Jiangsu Province(BK20170473,BK20160061)the Joint Open Fund of Jiangsu Collaborative Innovation Center for Ecological Building Material and Environmental Protection Equipment and Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province(JH201843)
文摘Tin dioxide (SnO2) has attracted broad interest due to its particular gas-sensor property. Nano- or atom-scale SnO2 material has always been the aim in order to ultimately improve the sensitivity. However, until now, it remains difficult to synthesize SnO2 nanoclusters by using traditional methods. In the present work, we have achieved the preparation of SnO2 nanoclusters by using the cluster beam deposition technique. The obtained nanoclusters were well characterized by high resolution transmission electron microscope HR-TEM. Results indicated the formation of the well-dispersed SnO2 nanoclusters with uniform size distribution (5-7 nm). Furthermore, an obvious metal insulator transition was observed by gating with ionic liquid. Combined with theory calculation, the corresponding mechanism was systematically analyzed from oxygen vacancy induced electron doping.
基金Financial supported by the Natural Science Foundation of China (No: 50003006)
文摘The uniform surface ion-imprinted resins for Zn2+ as the imprinting guest were prepared by emulsifier-free emulsion polymerization utilizing ally phenyl hydrogenphosphate as a functional comonomer. The Zn2+-imprinted resin adsorbed Zn2+ much more effectively than did the unimprinted one. The selective feature of the surface imprinted resins to the template ions was demonstrated.
文摘This paper studies the reaction between alkaline metal ions Li+, Na+ and K+ and ASR (alkali-silica reaction) reactive aggregates to determine whether Li+ can substitute Na+ and K+ that are unified in cement paste. Reactive aggregates use meta-sandstone from eastern Taiwan and Pyrex glass. Non-reactive aggregates use siliceous sand. The results show that the dissolved amount of SiO2 is lower when the reactive aggregates are immersed in an 80 ℃1 N LiOH'H20 solution than in NaOH and KOH solutions. The reduced amounts of OH and Li+ in the solution are also higher than those in the NaOH and KOH solutions. These results reveal that reactive SiO2 can react with LiOH to form a reactant with low water solubility. When the powder of the cement paste is immersed in an 80 ℃ 1 N LiOH-H2O solution, the amounts of free Na+ and K+ in the solution are higher than those in water. The increased amount increases with the duration of immersion. The amount of Li+ in the solution also decreases with the duration of immersion. These results reveal that Li+ can substitute Na+ and K+ that are unified in cement paste, which indicates that ASR can be prevented with the existence of Li+.
文摘Toxic Zn(II) ion imprinted interpenetrating polymer networks were synthesized for the selective sorption of Zn(ll) from aqueous solutions using a biopolymer alginic acid. The polymeric biosorbant was prepared using Zn(II) ion as template, acrylamide as functional monomer, cross linker NNMBA (N,N' Methylene-bis-acrylamide) and potassium persulphate as an initiator. The non-imprinted polymer networks were also prepared without use of the Zn(II) ion. The synthesized interpenetrating networks were characterized by various spectral techniques. Metal ion binding studies were carried out and the factors affecting binding were also optimized. Competitive sorption studies were investigated to determine the selectivity of Zn(II) ion imprinted interpenetrating polymer network. Zinc ion imprinted polymer networks showed good selectivity for the target ion.
基金Project(52004062)supported by the National Natural Science Foundation of ChinaProject(2020-MS-084)supported by the Natural Science Foundation of Liaoning Province,ChinaProject(N2125014)supported by the Fundamental Research Funds for the Central Universities,China。
文摘The electrochemical behavior of Al(Ⅲ)in urea-1-butyl-3-methylimidazolium chloride-aluminum chloride(urea-BMIC-AlCl_(3))ionic liquids,and the effect of potential and temperature on the characterization of cathode products,current efficiency and energy consumption of aluminum electrorefining have been investigated.Cyclic voltammetry showed that the electrochemical reduction of Al(Ⅲ)was a one-step three-electron-transfer irreversible reaction,and the electrochemical reaction was controlled by diffusion.The diffusion coefficient of Al(Ⅲ)in urea-BMIC-AlCl_(3)ionic liquids at 313 K was 1.94×10^(−7)cm^(2)/s.The 7075 aluminum alloy was used as an anode for electrorefining,and the cathode products were analyzed by XRD,SEM and EDS.The results from XRD analysis indicated that the main phase of the cathode products was aluminum.The results from SEM and EDS characterization revealed that the cathode product obtained by electrorefining−1.2 V(vs.Al)was dense and uniform,and the mass fraction of aluminum decreased from 99.61%to 99.10%as the experimental temperature increased from 313 K to 333 K.In this work,the optimum experimental conditions were−1.2 V(vs.Al)and 313 K.At this time,the cathode current efficiency was 97.80%,while the energy consumption was 3.72 kW·h/kg.
文摘Cerium-doped zirconium-based NH_(2)-UiO-66 nanoparticles were synthesized in ionic liquid 1-butyl-3-methylimidazolium acetate at room temperature.The crystal structure and morphology were studied using X-ray diffraction,infrared spectroscopy,scanning electron microscopy and transmission electron microscopy.The valence state and distribution of elements in the obtained materials were examined using X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy.Catalytic performance studies show that the cerium-doped NH_(2)-UiO-66 exhibits improved catalytic efficiency in the cycloaddition reaction of 1,2-butylene oxide and carbon dioxide than pure NH_(2)-UiO-66.Studies on the photoelectric properties indicate that the cerium-doped NH_(2)-UiO-66 catalyst possesses strong photocurrent response,low interfacial charge transfer resistance,narrow band gap,and low flat band potential.This work provides a new approach of synthesizing high-performance catalyst for photocatalytic CO_(2) cycloaddition.
基金supported by the National Natural Science Foundation of China (51174184)National Basic Research Program of China(2012CBA01202)SRF for ROCS, Ministry of Education of China
文摘This review summarizes the preparation methods of support ionic liquids (SILs) and their applications in rare metals separation The rare metals separation includes the recovery of high value metal ions and the removal of heavy metal ions from wastewater. SILs can be used as a kind of highly efficient multifunctional separation materials. The preparation methods of SILs include chemical immobilization technique in which ILs moieties are supported on solid supports via covalent bonds and physical immobilization techniques in which ILs are immobilized on solid supports via physical method such as simple im- pregnation, sol-gel method. According to the difference of solid supports, this review summarizes the application of polymer supported ionic liquids (P-SILs), silica based material supported ionic liquids (SM-SILs) and membrane supported ionic liq- uids (M-SILs) in rare metals separation, P-SILs and SM-SILs prepared by chemical method with N-methylimidazolium group can be used as highly efficient anion exchangers with high thermal stability and good chemical stability for adsorption of Cr(Ⅵ), Re(Ⅶ), Ce(Ⅳ). P-SILs prepared via simple impregnation afforded IL functionalized solvent impregnated resins (SIRs) which showed high separation efficiency and selectivity in the separation of rare earths(Ⅲ) (REs(Ⅲ)). SM-SILs prepared via sol-gel method with IL doped in the support as porogens or extractant show high removal efficiencies and excellent stability for the separation of RE(Ⅲ), Cr(Ⅲ) and Cr(Ⅵ). M-SILs with IL as plasticizer or carrier show improved stability, high perme- ability coefficient and good selectivity for Cr(VI) transport. Different supports and different supporting methods were suffi- ciently compared. Based on the different practical application, different forms of SILs can be prepared for separation of rare metals with high separation efficiency and selectivity.
基金supported by the National Natural Science Foundation of China (21472103)the Specialized Research Fund for the Doctoral Program of Higher Education (20130031110013)+1 种基金the Ministry of Education Innovation Team (IRT13022) of Chinathe "111" Project of Ministry of Education of China (B06005)
文摘Polyoxometalates(POMs) are a class of molecular metal oxides, showing numerous applications in various chemical processes due to their unique acid/base and redox features. By adjusting the tunable molecular structures of the anions and counter cations, plenty of POM-based ionic liquids(POM-based ILs) have been fabricated to be used in various fields, such as catalysis, structural chemistry and material science. As a class of excellent catalysts, POM-based ILs have shown advantages in the emerging field of CO_2 utilization such as CO_2 capture, cycloaddition of CO_2 to epoxides, and reduction of CO_2, owing to the efficient activation of CO_2 by POM anions. This review summarizes recent advances in the catalysis of POM-based ILs, and particularly highlights the areas that are related to CO_2 conversion.