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1.
3-Carboxy-4-hydroxyacetophenone (CHAP) was polycondensed with various proportions of formaldehyde using alcoholic alkali as catalyst. The resin samples, designated as CHAP-F, have been characterized by elemental analyses and IR spectroscopy, by estimation of their number average molecular weights (M?n), by measurement of intrinsic viscosity, and by TGA. Polymeric metal chelates of one CHAP-F sample with Cu2+, Fe3+, Co2+, Ni2+, and UO22+ ions have been prepared and characterized. Ion-exchanging properties of one CHAP-F resin sample for Fe3+, Cu2+, and Ni2+ metal ions are studied by the application of the batch-equilibration method.  相似文献   

2.
N‐heterocyclic acrylamide monomers were prepared and then transferred to the corresponding polymers to be used as an efficient chelating agent. Polymers reacted with metal nitrate salts (Cu2+, Pb2+, Mg2+, Cd2+, Ni2+, Co2+, Fe2+) at 150°C to give metal‐polymer complexes. The selectivity of the metal ions using prepared polymers from an aqueous mixture containing different metal ion sreflected that the polymer having thiazolyl moiety more selective than that containing imidazolyl or pyridinyl moieties. Ion selectivity of poly[N‐(benzo[d]thiazol‐2‐yl)acrylamide] showed higher selectivity to many ions e.g. Fe3+, Pb2+, Cd2+, Ni2+, and Cu2+. While, that of poly[N‐(pyridin‐4‐yl)acrylamide] is found to be high selective to Fe3+ and Cu2+ only. Energy dispersive spectroscopy measurements, morphology of the polymers and their metallopolymer complexes, thermal analysis and antimicrobial activity were studied. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42712.  相似文献   

3.
A sandwich-like 2D infinite framework of {[Cd(pbbm)2(SO3FcSO3)]·(CH3OH)2·(H2O)6} n (1) with nanosized porous structure [Fc(SO3)2Na2 = ferrocene-1,1′-disulphonate, pbbm = 1,1′-(1,3-propylene)-bis-1H-benzimidazole] was prepared by combining d 10 Cd2+ ions with highly conjugated pbbm and disodium ferrocene-1,1′-disulfonate. Experimental results show that 1 could serve as a new fluorescent probe for the detection of many divalent metal ions in water, such as Mn2+, Fe2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Ag+, Cd2+, Hg2+ and Pb2+, and trace organic solvents, including acetone, toluene, methylene chloride, ether, tetrahydrofuran, and methanol. The main product was very different from previous chemosensory materials that only identify one or two metal ions. The powdery multipurpose chemosensory materials proposed here could also sequester dangerous heavy metal ions, especially Pb2+. A computational study of ferrocene-1,1′-disulfonate and 1 gave insight into the process of ion exchange and sorption. This study introduces a promising new field of fluorescent chemosensors based on nanoporous coordination polymers with free functional groups.  相似文献   

4.
《分离科学与技术》2012,47(8):1629-1640
Abstract

A selective transport system for alkali and alkaline earth metallic ions with a perchlorate ion as a pairing ion species through a supported liquid membrane (SLM) containing tripentyl phosphate (TPP) as a carrier is described. The SLM used is a porous polypropylene membrane impregnated with TPP solution in o-nitrophenyloctylether. The effects of the pairing ion species, the initial perchlorate concentration, and the TPP concentration on metallic ion transportability are examined under various experimental conditions. The permeation velocities of the metallic ions in the transport system followed the sequence Li+?Na+>K+>Mg2+; that is, a highly selective transport for Li+ ion was observed. Compared with the transport rates of alkali metallic ions, those of transition metallic ions such as Cu2+ and Fe3+ ions are very low. The permeation velocities of alkali and alkaline earth metallic ions through an SLM are dependent on the concentrations of perchlorate and TPP. Equations for the permeation velocities of Li+, Na+, K+, and Mg2+ ions through an SLM, based on two concentrations of perchlorate and TPP, are proposed.  相似文献   

5.
A new single molecule multianalyte sensor, vanillic aldehyde rhodamine 6G hydrazone has been designed for the selective detection of Cu2+ and Hg2+ ions. UV/Vis spectroscopy indicates that the sensor is a good chromogenic chemosensor for Cu2+ in 1:99 (v/v) ethanol-water media. Whereas, other ions, such as Li+, Na+, Mg2+, K+, Ca2+, Cr3+, Mn2+, Fe3+, Co2+, Ni2+, Zn2+, Ag+, Cd2+, Ba2+, Hg2+ and Pb2+ failed to generate a distinct response. Fluorescence spectral data reveals that the sensor is an excellent fluorescent chemosensor for Hg2+ in aqueous ethanol solution and with no fluorescent response toward other ions. The spectroscopic behavior of the sensor in living cells indicated that it can be used for the detection of Cu2+ and Hg2+ in environmental and biological systems. Mechanisms for the high selectivity of the sensor to Cu2+ and Hg2+ are discussed.  相似文献   

6.
《分离科学与技术》2012,47(5):1277-1284
Abstract

A new heteropolyacid salt ion-exchanger, zirconium tungstoarsenate, has been used for preparing impregnated ion-exchange papers. Twenty-nine metal ions have been chromatographed and RF values determined in seven different mixed solvent systems containing 1-propanol and HNO3 or HCl. On the basis of the difference in selectivities for different metal ions on impregnated papers, a large number of binary and ternary separations has been obtained. Some of the important separations achieved are Ag+–Tl+, Ag+–Pt(IV), Zn2+–Hg2+, Sb3+–Bi3+, Zn2+–UO2 2+, Fe2+–Fe3+, Sb3+–Bi3+–Hg2+, Ag+–Ba2+–UO2 2+, and Ag+–Zn2+–Cu2+–Sn2+. The results are compared with those obtained on plain papers.  相似文献   

7.
《分离科学与技术》2012,47(12-13):1325-1344
Abstract

The aqueous-insoluble thia macrocycles tetrathia-14-crown-4 (TT14C4) and tetrathia-16-crown-4 (TT16C4) strongly and selectively synergize the extraction of Cu2+ and Ag+ ions from aqueous sulfuric acid solutions by the organophilic cation exchanger didodecylnaphthalene sulfonlc acid (HDDNS) in toluene diluent. Over a range of sulfuric acid concentrations, the selectivity is given by the order Ag2 > Cu2+ > Mn2+, Fe2+, Fe3+, Co2+, Ni2+, and Zn2+, where synergism occurs only for Ag+ and Cu2+. Selectivity factors greater than 300 have been achieved for Cu2+ over ubiquitous Fe3+. The synergistic extraction of Cu2+ and Ag+ was explored as a function of sulfuric acid concentration, relative concentration of macrocycle vs. HDDNS, and loading.  相似文献   

8.
《Ceramics International》2022,48(10):13833-13841
The current work describes the synthesis, structure, magnetic and optical properties of Cu1+ based delafossite oxides, Cu3(MFeSb)O6 (M = Na, Li) synthesized by the topotactic ion-exchange reactions (around 400 °C) of CuCl with Na4FeSbO6 and Na3LiFeSbO6 in an inert argon atmosphere. The synthetic procedure is significant as the oxides could not be synthesized by the solid state methods. Chemical analysis coupled with energy dispersive spectral analysis confirmed the extent of replacement of Na+ ions by Cu+ ions. A complete exchange of alkali metal ion, Na+ by Cu1+ in the interlayers of these honeycomb oxides has been achieved using a ratio of 1:3 between Na4FeSbO6 and CuCl. An additional exchange of approximately 70 % Na+ ions from the honeycomb arrays is possible by varying the ratio to 1:4. Rietveld refinements (space group C2/c) of the powder X-ray diffraction data have been carried out to ascertain the phase purity and to verify the structure formed by edge shared honeycomb arrays separated by Cu1+ in dumbbell configuration (O–Cu1+-O). X-ray photoelectron spectroscopy analysis confirmed the oxidation states of the constituent ions, specifically copper as Cu1+. A similar method is adopted to synthesize Cu3(LiFeSb)O6 by reacting Na3(LiFeSb)O6 and CuCl in the ratio 1:3 at 400 °C. These new delafossite oxides, Cu3(MFeSb)O6 (M = Na, Li) and Cu3((Cu0.7Na0.3)FeSb)O6, exhibit interesting magnetic properties which are significantly different from the rock salt based parent sodium analogs. Dominant antiferromagnetic interactions with a specific ordering temperature have been observed for these samples containing Fe3+ (d5) ions in the honeycomb. UV–visible diffuse reflectance measurements indicated the decrease in the band gap of Cu1+ based oxides. This study highlights the importance of low temperature ion-exchange reactions as an effective route to stabilize multifunctional materials of potential importance for various applications.  相似文献   

9.
A poly(vinyl alcohol) membrane (PVA) was modified by radiation graft copolymerization of acrylic acid/styrene (AAc/Sty) comonomers. The Cu and Fe ion‐transport properties of these membranes were investigated using a diaphragm dialysis cell. In the feed solution containing CuCl2 or a mixture of CuCl2 and FeCl3, the PVA‐g‐P(AAc/Sty) membranes showed high degrees of permselectivity toward Cu2+ rather than toward Fe3+. The permeation of Cu2+ ions through the membranes was found to increase with decrease in the grafting yield. However, as the content of Cu2+ ions in the Cu/Fe binary mixture feed solutions decreased, the rate and the amount of transported Cu2+ through the grafted membrane decreased, with no appreciable permselectivity toward Fe3+. When Fe2+ ions were used instead of Fe3+ ions in the feed solution containing Cu2+, the transport of both Cu2+ and Fe2+ through the membrane was observed. The rate of transport of Fe2+ was higher than that of Cu2+. In addition, it was found that the selective transport of ions was significantly influenced by the pH difference between both sides of the membranes. As the pH of the feed or the received solution decreased, both Cu2+ and Fe3+ passed through the membrane and were transported to the received solution. The role of carboxylic acid and the hydroxyl groups of the grafted membranes in the transportation process of ions is discussed. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 125–132, 2000  相似文献   

10.
《分离科学与技术》2012,47(16):2197-2201
Abstract

Copper has been selectively extracted from aqueous solutions containing metal ions (Cu2+, Co2+, Ni2+, Fe2+, Fe3+, Mg2+, and Zn2+) by a liquid membrane technique. Experiments were carried out in a beaker equipped with a baffle, and the system was stirred by a variable-speed mixer equipped with a turbine impeller; the mixing speed was 300 rpm. A typical membrane formulation was 2.0% Span 80, 4.0% LIX 860, and 94.0% of commercial kerosene, all values being by weight. Copper was selectively separated and concentrated from both synthetic and natural aqueous mine solutions containing various metal ions.  相似文献   

11.
《分离科学与技术》2012,47(10):2303-2314
Abstract

Potassium‐dicyclohexyl‐18‐crown‐6 was used as a selective and efficient carrier for the uphill transport of thallium (III) ion as [TlCl4]? complex ion through a chloroform bulk liquid membrane. By using oxalate anion as a metal ion acceptor in the receiving phase, the amount of thallium (III) transported across the liquid membrane after 120 min was 96±2%. The selectivity and efficiencies of thallium transport from aqueous solutions containing Cu2+, Zn2+, Ni2+, Cd2+, Pb2+, Co3+, Mn2+ , Cr3+, Mg2+, Ca2+, K+, Na+, and Fe3+ ions were investigated. In the presence of Na3PO4 (0.01 M) at pH=3 as a suitable precipitation agent in the source phase, the interfering effect of Pb2+ ion were diminished drastically.  相似文献   

12.
《分离科学与技术》2012,47(15):2423-2429
ABSTRACT

The effect of H+ ion concentration on the ion-exchange selectivity of Nafion 117 cation-exchange membrane toward Zn2+, Pb2+, Cu2+, Al3+, and Fe3+ have been studied. A selective transport of any particular metal ion was not possible by controlling the pH alone. However, selective permeation of Zn2+ across the membrane could be accomplished by selectively masking the metal ion as the cationic 1,10-phenanthroline complex while the permeation of other interfering ions could be suppressed by masking them as their anionic EDTA complex. About 20% of Zn2+ selectively permeated from the mixture in 6 hours and the quantity increased to 67% after 60 hours of permeation.  相似文献   

13.
The redox interactions of iron, manganese, and copper ion pairs including absorption characteristics in a multicomponent soda-lime-silica glass, were investigated. Glasses containing 11–19 mol % Na2O were melted under an air atmosphere in an electric furnace at 1450°C for 8 h. The results of chemical analysis indicated that the redox pairs of Fe2+/Fe3+, Mn2+/Mn3+, and Cu+/Cu2+ shift to more oxidized states as a function of increasing glass basicity. The redox interactions of individual pairs, e.g., Fe2+/Fe3+-Mn2+/Mn3+, Fe2+/Fe3+-Cu+/Cu2+, and Mn2+/Mn3+-Cu+/Cu2+, were not strong but changed with glass basicity. For the three redox pairs, Fe2+/Fe3+-Mn2+/Mn3+-Cu+/Cu2+, both Mn3+ and Cu2+ ions simultaneously and proportionally oxidized Fe2+ to Fe3+ and did not affect one another. The reaction constants log Q 2 of Fe2+/Fe3+-Mn2+/Mn3+ and Mn2+/Mn3+-Cu+/Cu2+ redox pairs decreased while the Fe2+/Fe3+-Cu+/Cu2+ and three redox pairs systems changed markedly with increasing the glass basicity. The oxidizing and reducing powers of each ion changed only slightly in the present of one another, and the absorption spectra of all the single polyvalent elements confirmed to the Lambert-Beer law. The spectra depended directly on the concentrations of each absorbing ion. While the spectra of glass doped with more than one element confirmed the direction of the equilibrium shift, they were used only to predict the degree of interaction. These investigations gave consistent results. The text was submitted by the authors in English.  相似文献   

14.
A new diblock copolymer, 1-methylpyrene isobutyrate–poly(methyl methacrylate–block-N-acryloyl-S-trityl-cysteine)-Br (Py–PMMA–b-ATCys-Br), was synthesized by atom transfer radical polymerization (ATRP) of N-acryloyl-S-trityl-L-cysteine monomer (ATCys) with 1-methylpyrene isobutyrate–poly(methyl methacrylate)–Br as a macroinitiator. The diblock copolymer and its precursor were characterized by 1H and 13C NMR spectroscopy, fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), gel permeation chromatography (GPC), and glass transition temperatures (Tg) measurements. Fluorescence properties of the diblock copolymer were investigated using various quenching (Cu2+, Hg2+, Fe2+, Fe3+, Co2+, Ni2+ and Pb2+) in dimethylformamide solutions, the more efficient quenchers being the Cu2+, Hg2+, Fe2+, and Fe3+ ions. In addition, the effect of in situ photogenerated silver nanoparticles on the copolymer fluorescence was also investigated.  相似文献   

15.
For the safe and trouble‐free operation of a manufacturing plant and the safe storage of acrylic, as well as methacrylic monomers, it is important to know the polymerization stability as a function of the process parameters (temperature, oxygen concentration, and impurities, e.g., metal ions). Contamination with metal ions can be caused by the corrosion of steel units. Therefore, the influence of the metal ions Cr3+, Fe3+, Ni2+ and Cu2+ in the concentration range of 0–10 ppm (g g–1) on the polymerization behavior and the oxygen consumption of acrylic and methacrylic acid were examined in this work. It was shown that Cr3+, Ni2+, and Cu2+ ions extend the inhibition period of acrylic acid (AA) and methacrylic acid (MAA) and reduce the O2 consumption. Fe3+ ions, however, cause a decrease of the inhibition period and in the case of AA an increase of the O2 consumption, which leads, in the end, to a faster unintentional polymerization. Therefore, alloys which contain iron should be avoided as far as possible in the construction of AA plants. Fe3+‐ions show the opposite influence towards MAA, here the presence of Fe3+ shows a stabilizing effect.  相似文献   

16.
Amberlite XAD‐2 has been functionalized by coupling through –SO2‐with ethylenediamine, propylenediamine, and diethylenetriamine to give the corresponding polyamine chelating resins I–III. The solid metallopolymer complexes of the synthesized chelating resins with Cu2+, Zn2+, Cd2+, and Pb2+ were synthesized. The polyamine derivatives and their metal complexes were characterized by elemental analysis, spectral (IR, UV/V, and ESR), and magnetic studies. The batch equilibrium method was utilized for using the chelating polyamines for the removal of Cu+2, Zn+2, Cd+2, and Pb+2 ions from aqueous solutions at different pH values and different shaking times at room temperature. The selective extraction of Cu+2 from a mixture of the four metal ions and the metal capacities of the chelating resins were evaluated using atomic absorption spectroscopy. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1839–1846, 2005  相似文献   

17.
A new adsorbent was developed by synthesizing 1,8‐diaminonaphthalene formaldehyde resin (DANFR) and coating it over the surface of silica gels. The silica composite was then treated with HCl for the activation of binding sites (?NH3+Cl?) on its surface. The structure of DANFR and its coating over the silanols were thoroughly characterized. Further, the adsorbent was applied to remove tungsten (W) from printed circuit board recycling unit wastewater that contained various co‐metal ions such as Na+, K+, Ca2+, Mg2+, Pb2+, NH4+, Zn2+, Cu2+ and Mn2+. The selective removal was achieved due to the anion exchange mechanism of Cl? with W(VI) while other cations get repelled from the surface (?NH3+) of the DANFR‐silica composite. X‐ray photoelectron spectroscopy studies, Raman spectra and overlay chromatograms of ion chromatography demonstrated selective separation of WO42? species from the wastewater. A removal capacity of 55.32 mg g?1 for W(VI) was achieved from the wastewater within 45 min of reaction (pH ca 6.0). Simultaneous treatment with neat aqueous solution of W brings out 63.27 mg g?1 of W(VI) removal. Finally, recovery of WO42? ions and regeneration of the adsorbent were carried out by using alkaline solution which demonstrated successful desorption, as investigated by using ion chromatography. © 2016 Society of Chemical Industry  相似文献   

18.
《分离科学与技术》2012,47(7):1223-1232
Abstract

A chloroform membrane system containing a given mixture of aza-18-crown-6 and palmitic acid was applied for the uphill transport of Pb2+ ions. In the presence of P2O7 4? ion as a suitable metal ion acceptor in the receiving phase, the amount of lead ion transported across the liquid membrane after 100 minutes is 89.1 ± 1.3%. The selectivity and efficiency of lead transport from aqueous solutions containing other cations such as Zn2+, Cu2+, Ni2+, Co2+, Fe2+, Pd2+, and Ag+ ions were investigated. In the presence of S2O3 2? ion as a proper masking agent in the source phase, the interfering effects of Cu2+ ion were diminished drastically.  相似文献   

19.
A novel organic–inorganic hybrid nanomaterial (SBA-15-CA) was prepared by covalent immobilization of chromotropic acid onto the surface of mesoporous silica material SBA-15. Different techniques such as XRD, TEM, FT-IR, N2 adsorption–desorption and TGA analyses were employed to characterize the grafting process. The data showed that the organic moiety (0.41 mmol g?1) was successfully grafted to the SBA-15 and the primary hexagonally ordered mesoporous structure of SBA-15 was preserved after the grafting procedure. SBA-15-CA has been realized as a highly sensitive and selective fluorescent probe towards Fe3+ and I? ions in aqueous media. SBA-15-CA exhibited a remarkable fluorescent quenching in the presence of Fe3+ ion over other competitive cations including Na+, Mg2+, Al3+, K+, Ca2+, Cr3+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, and Pb2+ as well as I? ion among a series of anions including F?, Cl?, Br?, CO32?, HCO3?, CN?, NO3?, NO2?, SCN?, SO42?, H2PO4?, HPO42?, and CH3COO?. A good linear response was observed between the concentration of the quenchers (Fe3+ and I? ions) and fluorescence intensity of SBA-15-CA with detection limits of 1.5?×?10?7 M for Fe3+ and 0.2?×?10?7 M for I?. Moreover, the effects of various pH values on the sensing ability of SBA-15-CA were investigated. Finally, the proposed method was successfully utilized for the determination of Fe3+ and I? ions in river water, well water and tap water samples.  相似文献   

20.
《分离科学与技术》2012,47(7):1002-1009
The synthesis of novel metal-free and magnesium porphyrazines, peripherally substituted with dithia-dioxa (S2O2) and tetrathia (S4) 14-membered macrocycles were performed by cyclotetramerization of (6Z)-1,3,4,9,10,12-hexahydro-2,5,8,11-benzo-dioxadithiacyclotetradecine-6,7-dicarbodinitrile (3) or (6Z)-1,3,4,9,10,12-hexahydro 2,5,8,11-benzotetrathiacyclotetradecine-6,7-dicarbodinitrile (5). The metal-free porphyrazines have been obtained by known route. The structure of compounds were characterized by elemental analysis and 1H, 13C NMR, IR, UV-vis, and MS spectral data. The solvent extraction properties of the synthesized compounds towards some metal cations, such as Ag(I), Hg(II), Cu(II), Mn(II), Cr(III), Ni(II), Pb(II), and Zn(II) have been investigated. The effect of Cu2+, Mn2+, Ni2+, Pb2+, Sr2+, Al3+, Zn2+, Ba2+, Cd2+, Co2+, Hg2+, and Ag+ ions on the absorption spectra of the compounds were investigated by means of spectrophotometric method. Magnesium porphyrazine with S2O2 (6) interacted within Hg2+ ion specifically of all the tested metal ions.  相似文献   

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