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1.
A new chelating polymer has been developed using Amberlite XAD-16 anchored with Quercetin. The modified polymer was characterised by Fourier Transform Infra Red (FTIR) spectroscopy, thermogravimetric analysis, surface area analysis and elemental analysis. The Quercetin anchored polymer showed superior binding affinity for Cr(III), Mn(II), Fe(III), Co(II), Ni(II) and Cu(II) with greater than 95% adsorption under optimum conditions. The optimum pH conditions for the quantitative sorption of metal ions were studied. The developed method showed superior extraction qualities with high metal loading capacities of 387, 313, 195, 473, 210 and 320 µmol g?1 for Cu(II), Co(II), Cr(III), Fe(III), Mn(II) and Ni(II), respectively. The rate of metal ion uptake i.e. kinetics studies performed under optimum levels, showed t 1/2 for Co(II), Cu(II), Cr(III), Fe(III), Mn(II) and Ni(II) is 20, 15, 25, 10, 30 and 15 min, respectively. Desorption of metal ions was effective with 10 mL of 2 M HCl prior to analysis using flame atomic absorption spectrophotometer. The chelating polymer was highly ion selective in nature even in the presence of interferent ions, with a high preconcentrating ability for the metal ions of interest. The developed chelating polymer was tested on its utility with synthetic and real samples like river, tap water samples and also with multivitamin tablets. It showed relative standard deviation (R.S.D.) values of/less than 3.0% reflecting on the accuracy and reproducibility of data using the newly developed chelating polymer.  相似文献   

2.
Two aromatic polyaminocarboxylate ligands, ethylenediaminedi(o-hydroxyphenylacetic acid) (EDDHA) and N,N′-bis(hydroxybenzyl)ethylenediamine-N,N′-diacetic acid (HBED), were applied for the separation of transition and heavy metal ions by the ion-exchange variant of electrokinetic chromatography. EDDHA structure contains two chiral carbon centers. It makes it impossible to use the commercially available ligand. All the studied metal ions showed two peaks, which correspond to meso and rac forms of the ligand. The separation of metal–HBED chelates was performed using poly(diallyldimethylammonium) polycations in mixed acetate–hydroxide form. Simultaneous separation of nine single- and nine double-charged HBED chelates, including In(III), Ga(III), Co(II)–(III) and Mn(II)–(III) pairs demonstrated the efficiency of 40 000–400 000 theoretical plates. The separation of Co(III), Fe(III) complexes with different arrangements of donor groups and oxidation of Co(II), Mn(II), Fe(II) ions in reaction with HBED have been discussed.  相似文献   

3.
Pathak R  Rao GN 《Talanta》1997,44(8):1447-1453
A poly[styrene-co-(divinylbenzene)] resin (XAD-4) functionalized with 1-hydrazinophthalazine ligand has been prepared and its analytical properties investigated. The pH dependence of sorption of metal ion on the resin has been determined for Cu(II), Ni(II), Co(II), Zn(II), Cd(II), Pb(II), Fe(III) and Cr(III). Trace amounts of these metal ions were quantitatively retained on the resin and recovered by eluting with 1 mol l(-1) hydrochloric acid. The resin was found to be selective for Fe(III) and its separation from other metal ions was carried out effectively. Metal ions concentrations were determined using AAS.  相似文献   

4.
Luminol-K2S2O8体系中金属离子化学发光行为的研究   总被引:1,自引:0,他引:1  
张新荣  章竹君 《化学学报》1987,45(2):195-197
报导了在自行设计的流动注射式化学发光分析仪上,对Luminal-K2S2O8体系中32种金属离子的化学发光行为的系统研究.确定了对金属离子的最优测定条件以及大多数金属离子的检出极限和线性范围.  相似文献   

5.
A new method that utilizes ethylenediamine-modified activated carbon (AC-EDA) as a solid-phase extractant has been developed for simultaneous preconcentration of trace Cr(III), Fe(III), Hg(II) and Pb(II) prior to the measurement by inductively coupled plasma optical emission spectrometry (ICP-OES). The new sorbent was prepared by oxidative surface modification. Experimental conditions for effective adsorption of trace levels of Cr(III), Fe(III), Hg(II) and Pb(II) were optimized with respect to different experimental parameters using batch and column procedures in detail. The optimum pH value for the separation of metal ions simultaneously on the new sorbent was 4.0. Complete elution of absorbed metal ions from the sorbent surface was carried out using 3.0 mL of 2% (%w/w) thiourea and 0.5 mol L−1 HCl solution. Common coexisting ions did not interfere with the separation and determination of target metal ions. The maximum static adsorption capacity of the sorbent at optimum conditions was found to be 39.4, 28.9, 60.5 and 49.9 mg g−1 for Cr(III), Fe(III), Hg(II) and Pb(II), respectively. The time for 94% adsorption of target metal ions was less than 2 min. The detection limits of the method was found to be 0.28, 0.22, 0.09 and 0.17 ng mL−1 for Cr(III), Fe(III), Hg(II) and Pb(II), respectively. The precision (R.S.D.) of the method was lower 4.0% (n = 8). The prepared sorbent as solid-phase extractant was successfully applied for the preconcentration of trace Cr(III), Fe(III), Hg(II) and Pb(II) in natural and certified samples with satisfactory results.  相似文献   

6.
A novel method that utilizes 1-(2-formamidoethyl)-3-phenylurea-modified activated carbon (AC-1-(2-formamidoethyl)-3-phenylurea) as a solid-phase extractant has been developed for simultaneous preconcentration of trace Cr(III), Cu(II), Fe(III) and Pb(II) prior to the measurement by inductively coupled plasma atomic emission spectrometry (ICP-AES). Experimental conditions for effective adsorption of trace levels of Cr(III), Cu(II), Fe(III) and Pb(II) were optimized using batch and column procedures in detail. The optimum pH value for the separation of metal ions simultaneously on the new sorbent was 4. And the adsorbed metal ions could be completely eluted by using 2.0 mL 2.0 mol L−1 HCl solution. Common coexisting ions did not interfere with the separation and determination of target metal ions. The maximum static adsorption capacity of the sorbent at optimum conditions was found to be 39.8, 39.9, 77.8 and 17.3 mg g−1 for Cr(III), Cu(II), Fe(III) and Pb(II), respectively. The detection limits of the method were found to be 0.15, 0.41, 0.27 and 0.36 ng mL−1 for Cr(III), Cu(II), Fe(III) and Pb(II), respectively. The relative standard deviation (RSD) of the method was lower than 4.0% (n = 8). The method was successfully applied for the preconcentration of trace Cr(III), Cu(II), Fe(III) and Pb(II) in natural and certified samples with satisfactory results.  相似文献   

7.
Silica gel was firstly functionalized with aminopropyltrimethoxysilane obtaining the aminopropylsilica gel (APSG). The APSG was reacted subsequently with curcumin yielding curcumin-bonded silica gel (curcumin-APSG). This new bonded silica gel was used for separation, pre-concentration and determination of Cu(II), Fe(III), Zn(II) in biological and natural water samples by inductively coupled plasma optical emission spectrometry (ICP-OES). Experimental conditions for effective adsorption of trace levels of metal ions were optimized with respect to different experimental parameters using batch and column procedures in detail. The optimum pH value for the separation of metal ions simultaneously on the newly sorbent was 4.0. Complete elution of the adsorbed metal ions from the sorbent surface was carried out using 2.0 mL of 0.1 mol L− 1 of HCl. Common coexisting ions did not interfere with the separation and determination at pH 4.0. The maximum static adsorption capacity of the sorbent at optimum conditions was found to be 0.63, 0.46 and 0.37 mmol g− 1 for Cu(II), Fe(III) and Zn(II) respectively. The time for 95% sorption for Cu(II) Fe(III) and Zn(II) was less than 2 min. The detection limits of the method defined by IUPAC was found to be 0.12, 0.15 and 0.40 ng mL− 1 for Cu(II), Fe(III) and Zn(II), respectively. The relative standard deviation (RSD) of the method under optimum conditions was lower 3.0% (n = 5). The procedure was validated by analyzing the certified reference river sediment material (GBW 08301, China), the results obtained were in good agreement with standard values. This sorbent was successfully employed in the separation and pre-concentration of trace Cu(II), Fe(III) and Zn(II) from the biological and natural water samples yielding 75-fold concentration factor.  相似文献   

8.
A 5-formyl-3-(1′-carboxyphenylazo) salicylic acid-bonded silica gel (FCPASASG) chelating adsorbent was synthesized according to a very simple and rapid one step reaction between aminopropyl silica gel (APSG) and 5-formyl-3-(1′-carboxyphenylazo) salicylic acid (FCPASA) and its adsorption characteristics were studied in details. Nine trace metals viz.: Cd(II), Zn(II), Fe(III), Cu(II), Pb(II), Mn(II), Cr(III), Co(II) and Ni(II) can be quantitatively adsorbed by the adsorbent from natural aqueous systems at pH 7.0–8.0. The adsorbed metal ions can be readily desorbed with 1 M HNO3 or 0.05 M Na2EDTA. The distribution coefficient, Kd and the percentage concentration of the investigated metal ions on the adsorbent at equilibrium, CM,eqm % (Recovery, R%) were studied as a function of experimental parameters. The logarithmic values of the distribution coefficient, logKd, are 3.7–6.4. Some foreign ions caused little interference in the preconcentration and determination of the investigated nine metals by flame atomic absorption spectrometry (AAS).The adsorption capacity of FCPASASG was 0.32–0.43 meq g−1. C and N elemental analyses of the adsorbent (FCPASASG) allowed us to calculate a surface converge of 0.82 mmol g−1. This value compares well with the best values reported for the azo compounds. The adsorbent and its formed metal chelates were characterized by IR (absorbance and/or reflectance) and UV spectrometry, potentiometric titrations and thermogravimetric analysis (TGA and DTG). The mode of chelation between the FCPASASG adsorbent and the investigated metal ions is proposed to be due to reaction of those metal ions with the salicylic and/or the carboxyphenylazo chelation centers of the FCPASASG adsorbent. Nanogram concentrations (0.07–0.14 ng ml−1) of Cd(II), Zn(II), Fe(III), Pb(II), Cr(III), Mn(II), Cu(II), Co(II) and Ni(II) can be determined reliably with a preconcentration factor of 100.  相似文献   

9.
A new solid-phase extraction method utilising polyacrylonitrile activated carbon fibres (PAN-ACFs) as adsorbent was developed for the preconcentration of trace metal ions prior to their determination by inductively coupled plasma optical emission spectrometry (ICP-OES). The PAN-ACFs oxidised with nitric acid were characterised by FT-IR, XRD, SEM and BET analysis. Then the resulting PAN-ACFs were used as solid-phase adsorbent for simultaneously determination of trace Al(III), Be(II), Bi(III), Cr(III), Cu(II), Fe(III) and Pb(II) ions in aqueous solutions. The influences of the analytical parameters on the recoveries of the studied ions were investigated. The optimum experimental conditions of the proposed method were pH: 6.0; eluent concentration and volume: 3.0 mL of 1.5 mol L?1 nitric acid; flow rates of sample and eluent solution: 1.5 mL min?1. The preconcentration factors were found to be 67 for Al(III), Bi(III); 83 for Cr(III), Cu(II), Fe(III) and 50 for Be(II), Pb(II). The precision of this method was in range of 1.5%~3.5% and the detection limit of this metal ions was between 0.06~1.50 μg L?1. The developed method was validated by the analysis of a certified reference sample and successfully applied to the determination of trace metal ions in water samples with satisfactory results.  相似文献   

10.
Summary A method is described for functionalizing acetoacetamide chelating groups onto microcrystalline cellulose (Cell-AcAc). This material shows a significant affinity for Fe(III), Cu(II) and U(VI) and no or very less affinity for the M(I) ions (M=Na, K), M(II) ions (M= Mg, Ca; Fe, Co, Ni, Zn), La(III) and Y(III) including Th(IV). The obtained K d values offer a column separation method for U(VI) ions from the rest of above-mentioned metal ions except Fe(III). Cell-AcAc and its Cu(II) complexes are characterized by means of FT-IR spectra.
Darstellung, Charakterisierung und Anwendung von Ionenaustauschmaterial aus Cellulose mit chemisch gebundener Acetoacetamid-Gruppe
Zusammenfassung Die Darstellung von immobilisiertem Acetoacetamid auf mikrokristallinem Cellulosepulver (Cell-AcAc) wird beschrieben. Der Ionenaustauscher Cell-AcAc hat eine ausgeprägte Affinität für Fe(III), Cu(II) and U(VI), aber nahezu keine für die M(I)-Ionen (M=Na, K) M(II)-Ionen (M=Mg, Ca; Fe, Co, Ni, Zn), La(III), Y(III) sowie Th(IV). Die erhaltenen K d-Werte ermöglichen für U(VI)-Ionen eine quantitative säulen-chromatographische Trennung von den anderen genannten Kationen mit Ausnahme von Fe(III). Das Ionenaustauschmaterial Cell-AcAc und sein Cu(II)-Komplex wurden durch FT-IR-Spektren charakterisiert.
  相似文献   

11.
New series of nano‐sized bi‐homonuclear Ce (III), ZrO (II), Sn (II), Pb (II), Cr (III), Fe (III) and Cu (II) complexes with 4‐[(2,4‐dihydroxybenzylidene)amino]‐N‐(1,3‐thiazol‐2‐yl) benzenesulfonamide (H3L) were synthesized via green solid‐state method. The structural and molecular formulae of all synthesized complexes were established based on variable spectral, analytical and theoretical implementations. FT‐IR study confirms the coordination of H3L with metal ions through the Schiff base and sulfonamide centers in di‐basic tetra‐dentate mode. Thermal analysis, magnetic moment and electronic spectra are attributing to octahedral configuration around Ce (III), Cr (III) and Fe (III) centers, while with ZrO (II), Sn (II), Pb (II) and Cu (II) centers, acquired tetrahedral arrangement. TEM and XRD studies, represent the nanometer characters of most metal ion complexes. TGA curves are utilized to compute the activation thermo‐kinetic parameters over different decomposition stages applying Coats‐Redfern method. Theoretical implementation executed by Gaussian09 program exerted the structures for the best atomic orientation over whole molecules. QSAR data were achieved over Hyper Chem 8.1 program through molecular mechanics process. Docking complexes between free ligand and different protein receptors were obtained through AutoDock Tools 4.2. Antimicrobial, antifungal and antitumor activities of the metal complexes were studied in comparing with free ligand to assert their potential therapeutic uses. H3L, Ce (III), Fe (III) and Cu (II) complexes displayed high antibacterial activity near that of standard Gentamycin. Moreover, Cr (III) complex displayed highest cytotoxicity against human liver Carcinoma cell line (HEPG2).  相似文献   

12.
Crosslinked acrylonitrile/acrylamidoxime/2-acrylamido-2-methylpropane sulfonic acid (AN/AAx/AMPS) based hydrogels was prepared by radical solution polymerization technique. The structures of hydrogels were characterized by FTIR analysis and the results were consistent with the expected structures. These hydrogels were used for the separation of Cd(II), Cu(II), and Fe(III) ions from their aqueous solutions. The influence of the uptake conditions such as pH, time, and initial feed concentration on the metal ion binding capacity of hydrogel was also tested. The selectivity of the hydrogel toward the different metal ions tested was Cd(II)>Fe(III)>Cu(II). The recovery of metal ions was also investigated in acid media.  相似文献   

13.
Differentiation between two isomers of hydroxypyridine N-oxide according to the metal cation adducts generated by electrospray ionization (ESI) was investigated for different metal cations, namely Mg (II), Al (III), Ca (II), Sc (III), Fe (III), Co (II), Ni (II), Cu (II), Zn (II), Ga (III), besides the diatomic cation VO(IV). Protonated molecules of the isomeric hydroxypyridine N-oxides as well as the singly/doubly charged adducts formed from neutral or deprotonated ligands and a doubly/triply charged cation were produced in the gas phase using ESI, recording mass spectra with different metal ions for each isomer. While complex formation was successful for 2-hydroxypyridine N-oxide with trivalent ions, in the case of 3-hydroxypyridine N-oxide, only peaks related to the protonated molecule were present. On the other hand, divalent cations formed specific species for each isomer, giving characteristic spectra in every case. Hence, differentiation was possible irrespective of the metal cation utilized. In addition, quantum chemical calculations at the B3LYP/6-31 + G(d,p) level of theory were performed in order to gain insight into the different complexation of calcium(II) with the isomers of hydroxypyridine N-oxide. The relative stability in the gas phase of the neutral complexes of calcium made up of two ligands, as well as the singly charged and doubly charged complexes, was investigated. The results of these calculations improved the understanding of the differences observed in the mass spectra obtained for each isomer.  相似文献   

14.
The complexation tendencies of N,N-di-(-hydroxyethyl)-dithiocarbamic acid [DEADTCH, (CH2CH2OH)2NCSSH] towards a large number of metal ions have been examined. The complexes formed with transition and post-transition metal ions in slightly acidic and neutral solutions have the general formulaM(DEADTC) x, wherex is the valence state of the metal,M=Cr(III), Fe(III), Co(III), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II), Tl(I), and Tl(III). In addition the interesting mixed ligand complex ClHg(DEADTC) was prepared. These complexes have been characterised through X-ray, magnetic, conductance and spectral (UV and IR) measurements.  相似文献   

15.
Yun J  Choi H 《Talanta》2000,52(5):893-902
1-Nitroso-2-naphthol, an excellent color-forming chelating agent, combines to Fe(III), Co(II), Ni(II), Cu(II) and so on to form slightly soluble complexes in aqueous solution. To determine these metal ions, a tedious and time consuming separation technique, such as liquid-liquid extraction, has often been performed. However, these metal-1-nitroso-2-naphthol complexes could be determined conveniently by ultraviolet-visible (UV-Vis) spectrophotometry in Tween 80 micellar medium that has polyoxyethylene groups. After conditions such as pH, the amount of 1-nitroso-2-naphthol and the stability were adjusted to their optimum values, the sensitivities of the metal ions in Tween 80 medium and in chloroform were compared. It was shown that the sensitivities of Fe(III) and Co(II) in Tween 80 medium were higher than in chloroform, but that of Cu(II) was lower. The interfering effects among analytes ions, Fe(III), Co(II), Ni(II) and Cu(II) were more serious than by other ions, but the interfering effects could be removed by adjusting pH or adding the masking agents such as NH(3) or oxalate. Detection limits of Fe(III), Co(II), Ni(II), and Cu(II) were 0.024, 0.016, 0.039 and 0.023 mug ml(-1), respectively, and the correlation coefficients of these calibration curves were above 0.996. Recovery yields of the metal ions in the mixed standard solution ranged from 96 to 103%, and their coefficients of variation were low ranging between 0.94 and 1.75%. Cu(II) in brass sample and the amount of Fe(III) in steel sample were also determined. This proposed technique is simple, convenient and speedy.  相似文献   

16.
In a search for environmentally friendly metal chelating ligands for industrial applications, the protonation and complex formation equilibria of [S,S,S]- and [R,S,R]-isomers of N-bis[2-(1,2-dicarboxyethoxy)ethyl] aspartic acid (BCA6) with Mg(II), Ca(II), Mn(II), Fe(III), Cu(II) and Zn(II) ions in aqueous 0.1 M NaCl solution were studied at 25°C by potentiometric titration. The model for complexation and the stability constants of the different complexes were determined for each metal ion using the computer program SUPERQUAD. With all metal ions (M n+), stable ML n?6 complexes dominated complex formation for both isomers. Differences in complexation models were found for binuclear species.  相似文献   

17.
Co(II), Cu(II), Zn(II), and Fe(III) complexes of phenylthiourea have been synthesized and characterized by elemental analyses, molar conductivity, magnetic susceptibility, FT-IR, and electronic spectroscopy. The spectroscopic data of the complexes are consistent with four-coordinate geometry for the metal(II) complexes and six-coordinate octahedral for the Fe(III) complex. Single crystal X-ray analysis of the Zn(II) complex revealed distorted tetrahedral geometry around the metal ion with two molecules of phenylthiourea and two acetate ions. The in vitro antibacterial activity of the complexes was studied against six bacterial strains using disc diffusion and broth microdilution methods. The complexes showed selective antibacterial activity against Staphylococcus aureus and Bacillus pumilus when compared to standard antibiotic ampicillin. The minimum inhibitory concentrations of the sensitive compounds are between 0.625 and 5.0 mg mL?1.  相似文献   

18.
The radical copolymerization of acrylic acid with acrylamide was carried out at different monomer ratios in solution (DMF) at 60°C. The corresponding homopolymers were also synthesized to compare their metal ion binding abilities. All the copolymers were characterized by elemental analysis. The metal ion binding properties of these water-soluble polymers with Cu(II), Co(II), Ni(II), Cd(II), Zn(II), Pb(II), Hg(II), Fe(III), and Cr(III) ions were investigated in aqueous solution using the Liquid-Phase Polymer-Based Retention (LPR) technique. Poly(acrylic acid-co-acrylamide) showed a higher retention compared to the homopolymers for all the metal ions except of Hg(II), which was not retained. Besides, the retention of Cd(II) is higher than that an addition of the retention of both homopolymers. It may be attributed to a synergic effect. Maximum capacity for Cu(II) at pH 5.0 was determined to be 1 mmol g−1 (63.5 mg g−1). © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2461–2467, 1997  相似文献   

19.
Two aromatic polyaminocarboxylate ligands, ethylenediaminedi(o-hydroxyphenylacetic acid) (EDDHA) and N,N′-bis(hydroxybenzyl)ethylenediamine-N,N′-diacetic acid (HBED), were applied for the separation of transition and heavy metal ions by the ion-exchange variant of electrokinetic chromatography. EDDHA structure contains two chiral carbon centers. It makes it impossible to use the commercially available ligand. All the studied metal ions showed two peaks, which correspond to meso and rac forms of the ligand. The separation of metal–HBED chelates was performed using poly(diallyldimethylammonium) polycations in mixed acetate–hydroxide form. Simultaneous separation of nine single- and nine double-charged HBED chelates, including In(III), Ga(III), Co(II)–(III) and Mn(II)–(III) pairs demonstrated the efficiency of 40 000–400 000 theoretical plates. The separation of Co(III), Fe(III) complexes with different arrangements of donor groups and oxidation of Co(II), Mn(II), Fe(II) ions in reaction with HBED have been discussed.  相似文献   

20.
Fluorescence probes NA1 and NA2 derived from 1-naphthylamine (NA) as fluorophore have been synthesized and characterized by different spectroscopic studies. Identification behaviour of these probes towards various metal ions has been investigated. Both the fluorescent probes are selective as well as sensitive towards Fe(III) ion. Novel fluorescence probe NA2 afforded turn-on fluorescence behaviour for Fe(III) ion over other metal ions such as Ca(II), Mg(II), Mn(II), Fe(II), Co(II), Fe(III), Ni(II), Cu(II), Zn(II) and Hg(II).  相似文献   

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