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1.
Summary. A new polymeric resin with sulfonamide pendant functions has been prepared for the selective extraction of mercuric ions.
This polystyrene sulfonamide urea resin with a 3.5 mmol/g total nitrogen content is able to selectively sorb mercury from
aqueous solutions. The mercury sorption capacity of the resin is around 1.60 mmol/g under non-buffered conditions. The experiments
performed under identical conditions with some metal ions reveal that Cd(II), Pb(II), Zn(II), and Fe(III) ions are also extractable
in low quantity (0.05–0.1 mmol/g). The sorbed mercury can be eluted by repeated treatment with hot acetic acid without hydrolysis
of the amide groups. 相似文献
2.
Naracham Veedu Sreekumar Ronald Aquin Nazareth Badiadka Narayana Prashant Hegde Busnur Rachotappa Manjunatha 《Mikrochimica acta》2002,140(1-2):63-67
A complexometric method for the determination of mercury in presence of other metal ions based on the selective masking ability
of potassium bromide towards mercury is described. Mercury(II) present in a given sample solution is first complexed with
a known excess of EDTA and the surplus EDTA is titrated against zinc sulfate solution at pH 5–6 using xylenol orange as the
indicator. A known excess of 10% solution of potassium bromide is then added and the EDTA released from Hg-EDTA complex is
titrated against standard zinc sulfate solution. Reproducible and accurate results are obtained for 8 mg to 250 mg of mercury(II)
with a relative error ± 0.28% and standard deviations ≤0.5 mg. The interference of various ions is studied. This method was
applied to the determination of mercury(II) in its alloys.
Received April 18, 2001 Revision October 10, 2001 相似文献
3.
A new chelating resin incorporating imidazolyl azo groups into a matrix of polystyrene divinylbenzene has been prepared.
The exchange capacity of the resin for the ions mercury(II), silver(I) and lead(II) as a function of pH has been determined.
The resin exhibits no affinity to alkali, or alkaline earth metals. It is highly selective for only mercury(II) and silver(I).
In column operation it has been observed that mercury(II) in trace quantities is very effectively removed from river water
spiked with mercury(II) at the usual pH of natural waters.
Received: 2 January 1996/Revised: 11 April 1996/Accepted: 16 April 1996 相似文献
4.
An “off–on” rhodamine-based fluorescence probe for the selective signaling of Cr(III) has been designed by exploiting the
guest-induced structure transform mechanism. This system shows a sharp Cr(III)-selective fluorescence enhancement response
in 100% aqueous system under physiological pH value and possesses high selectivity against the background of environmentally
and biologically relevant metal ions including Cr(VI), Al(III), Fe(III), Cd(II), Co(II), Cu(II), Ni(II), Zn(II), Mg(II), Ba(II),
Pb(II), Na(I), and K(I). Under optimum conditions, the fluorescence intensity enhancement of this system is linearly proportional
to Cr(III) concentration from 5.0 × 10−8 to 7.0 × 10−6 mol L−1 with a detection limit of 1.6 × 10−8 mol L−1. 相似文献
5.
Vibha Saxena Vinay Shirodkar Rajiv Prakash 《Journal of Solid State Electrochemistry》2000,4(4):234-236
A device has been developed for the measurement of copper(II) ions (Cu2+) in aqueous medium. The device reported here is an electrochemical transistor which consists of two platinum electrodes separated
by 100 μm spacing and bridged with an anodically grown film of polycarbazole. Polycarbazole film (undoped form) is observed
to be highly selective for the Cu(II) ions. In a completed device, the conductivity of the polycarbazole film changes on addition
of Cu(II) ions. The change in conductivity is attributed to the conformational changes in the polymer phase on occupation
of the Cu(II) ions, without affecting electron/proton transfer. The device turns on by adding 2.5 × 10−6 M Cu(II) ions and reaches a saturation region beyond 10−4 M Cu(II) ion concentrations. In the above concentration range, the device response [I
D vs. log Cu(II) ion concentration] is linear. The selectivity of the device for other metal ions such as Cu(I), Ni(II), Co(II),
Fe(II), Fe(III), Zn(II) and Pb(II) is also studied.
Received: 6 April 1999 / Accepted: 20 August 1999 相似文献
6.
H. Bulbul Sonmez B. F. Senkal N. Bicak 《Journal of polymer science. Part A, Polymer chemistry》2002,40(17):3068-3078
Poly(acrylamide) grafted from solid polymer particles provides a simple solution for extremely selective removal of mercuric ions from aqueous solutions. The grafting of polyacrylamide has been performed, in high yields (164%), by redox initiation from iminoacetic acid groups created on crosslinked spherical beads (210–420 μm) of glycidyl methacrylate/methyl methacrylate/ethylene glycol dimethacrylate terpolymer. In the grafting, homopolymer formation has been reduced greatly (22%) by the treatment of the bead polymer with ceric ammonium nitrate before the addition of acrylamide monomer. The mobility of the graft chains provides nearly homogeneous reaction conditions and rapid mercury binding ability, as for low molecular weight amides [mercury sorption by a 0.105‐g polymer sample from 105 mL of a 7.74 × 10?4 mol L?1 (~155 ppm) Hg(II) solution shows first‐order kinetics with respect to the Hg(II) concentration, k = 1.1 × 10?3 s?1]. The mercury sorption capacity under nonbuffered conditions is around 3.6 mmol g?1 (i.e., 720 g of mercury/kg) and mostly occurs with the formation of diamido–mercury linkages, which result in the crosslinking of polyacrylamide brushes outside the spherical beads. The crosslinks can be destroyed by treatment with hot acetic acid, without hydrolysis of the amide groups. This process allows a complete elution of the mercury as mercury acetate, and the overall result is reversible crosslinking of the outer shell by mercuric ions. The material presented is efficient in the removal of mercury at concentrations measured in parts per million, and the mercury sorption is extremely selective over some foreign ions, such as Fe(III), Cd(II), Zn(II), and Pb(II). © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3068–3078, 2002 相似文献
7.
Akhmad Sabarudin Osamu Noguchi Mitsuko Oshima Keiro Higuchi Shoji Motomizu 《Mikrochimica acta》2007,159(3-4):341-348
Chitosan resin functionalized with 3,4-dihydroxy benzoic acid (CCTS-DHBA resin) was used as a packing material for flow injection
(FI) on-line mini-column preconcentration in combination with inductively coupled plasma-atomic emission spectrometry (ICP-AES)
for the determination of trace elements such as silver, bismuth, copper, gallium, indium, molybdenum, nickel, uranium, and
vanadium in environmental waters. A 5-mL aliquot of sample (pH 5.5) was introduced to the minicolumn for the adsorption/preconcentration
of the metal ions, and the collected analytes on the mini-column were eluted with 2 M HNO3, and the eluates was subsequently transported via direct injection to the nebulizer of ICP-AES for quantification. The parameters
affecting on the sensitivity, such as sample pH, sample flow rate, eluent concentration, and eluent flow rate, were carefully
examined. Alkali and alkaline earth metal ions commonly existing in river water and seawater did not affect the analysis of
metals. Under the optimum conditions, the method allowed the determination of metal ions with detection limits of 0.08 ng mL−1 (Ag), 0.9 ng mL−1 (Bi), 0.07 ng mL−1 (Cu), 0.9 ng mL−1 (Ga), 0.9 ng mL−1 (In), 0.08 ng mL−1 (Mo), 0.09 ng mL−1 (Ni), 0.9 ng mL−1 (U), and 0.08 ng mL−1 (V). By using 5 mL of sample solution, the enrichment factor and collection efficiency were 8–12 fold and 96–102%, respectively,
whereas the sample throughput was 7 samples/hour. The method was validated by determining metal ions in certified reference
material of river water (SLRS-4) and nearshore seawater (CASS-4), and its applicability was further demonstrated to river
water and seawater samples. 相似文献
8.
A selective complexometric method for the determination of mercury(II) in the presence of associated metal ions is reported,
based on the selective masking ability of 2-mercaptopropionylglycine (MPGH2) towards mercury. Mercury, along with other associated metal ions, is first complexed with excess of EDTA and the surplus
EDTA is back titrated at pH 5–6 (hexamine buffer) with standard zinc sulfate solution using xylenol orange as indicator. An
aqueous 1% solution of MPGH2 is then added to displace EDTA selectively from the Hg-EDTA complex and the released EDTA is titrated with the same standard
zinc sulfate solution. Reproducible and accurate results are obtained for 4–85 mg of mercury with a relative error of ≤ 0.26%
and coefficient of variation not exceeding 0.42%. The interferences of various cations and anions are studied. The method
is used for the analysis of mercury in its complexes and alloy samples.
Received August 30, 2000. Revision January 15, 2001. 相似文献
9.
The integration of an urease reactor into a gas diffusion flow injection system was investigated for the determination of
urease inhibitors. The enzyme was immobilized by entrapping in polyacrylamide gel. Besides copper and silver ions mercury
ions inhibit the conversion of urea to carbon dioxide and ammonia catalysed by urease. The pH change of the carrier solution
caused by the ammonia released was measured potentiometrically with a pH electrode. The inhibition behaviour of Hg(II) ions
was investigated. A linear range from 2 to 20 μg L-1 Hg(II) was obtained after a 90 s inhibition, with a correlation coefficient of r=0.9997. The relative standard deviation
was 1.4% for five measurements of 2 μg L-1Hg(II). A sample frequency of 7 h-1 was achieved. The inhibited enzyme can be reactivated. The method was applied to the determination of Hg(II) in two drinking
water samples.
Received: 16 April 1996/Revised: 3 June 1996/Accepted: 11 June 1996 相似文献
10.
The functional group capacity and the percentage of functional group conversion of crosslinked polystyrene resin bearing N-methyl-2-thioimidazole (MTIR) synthesized under optimum conditions are as high as 4.08 mmol/g resin and 96.0%, respectively. The apparent activation energies of sorption of MTIR for Au(III) and Pt(IV) are 13.1 and 13.4 kJ/mol, respectively. The sorption behavior of MTIR for Au(III), Pt(IV), and Pd(II) obeys the Freundlich and Langmuir isotherms. The sorption capacities of MTIR for Au(III), Pt(IV), and Pd(II) are as high as 4.33, 2.12, and 2.33 mmol/g resin, respectively. Au(III), Pt(IV), and Pd(II) adsorbed on MTIR can be eluted quantitatively by the eluant. The resin can be regenerated easily and reused without an obvious decrease in the sorption capacity for Au(III) and Pd(II). The resin has high sorption selectivity for noble metal ions. Au(III) can be separated quantitatively in the presence of high concentrations of Cu2+, Fe3+, Ni2+, and Mn2+. The recovery of platinum from the spent industrial catalysts is 98.6% by MTIR. The preconcentration and separation of palladium and platinum from the anode deposits of electrolysis of crude copper have been investigated. The resin may have potential industrial uses. 相似文献
11.
5,10,15,20-tetrakis(phenoxy acetic acid) porphyrin (PAAP) was covalently linked to Merrifield chloromethylated resin. Characterization
of PAAP and the modified polymeric matrix were performed by 1H NMR, FTIR and elemental analysis. The sorbent was used for the separation and enrichment of the d-electron metals (Mn(II), Co(II), Ni(II), Cu(II) and Zn(II)) at pH 6–8 and of the f-electron metals U(VI) and Th(IV) at pH 4–5. The metals ions were preconcentrated with a concentration factor range of 115–215
and then determined by flame atomic absorption spectrometry or visible spectrophotometry using Arsenazo(III). The retained
metals were eluted with 2.0 mol L−1 HNO3 in the case of the d-electron metals and 0.1/0.25 mol L−1 HCl in the case of the f-electron metals. The procedure was validated by analyzing the NIST standard reference material 2709 (San Joaquin Soil).
Correspondence: Melek Merdivan, Chemistry Department, Faculty of Arts and Sciences, Dokuz Eylul University, 35160 Buca, Izmir,
Turkey 相似文献
12.
A new chelating resin, 1-(2-pyridylazo)-2-naphthol (PAN) coated Amberlite XAD-1180 (AXAD-1180), was prepared and used for
the preconcentration of Cd(II), Mn(II), Ni(II), Pb(II) and Zn(II) ions prior to their determination by flame atomic absorption
spectrometry (FAAS). The optimum pH for simultaneous retention of the elements and the best elution means for their simultaneous
elution were pH 9.5 and 3 M HNO3, respectively. The sorption capacity of the resin was found to be 5.3 mg/g for Cd and 3.7 mg/g for Ni. The detection limits
for Cd(II), Mn(II), Ni(II), Pb(II) and Zn(II) were 0.7, 10, 3.1, 29 and 0.8 μg/L, respectively. The effects of interfering
ions for quantitative sorption of the metal ions were investigated. The preconcentration factors of the method were in the
range of 10–30. The recoveries obtained were quantitative (≥95%). The standard reference material (GBW07605 Tea sample) was
analysed for accuracy of the described method. The proposed method was successfully applied to the analysis of various water,
urea fertilizer and tea samples.
The article is published in the original. 相似文献
13.
Alain Walcarius Jérôme Devoy Jacques Bessiere 《Journal of Solid State Electrochemistry》2000,4(6):330-336
Pure silica particles were dispersed within carbon paste and the resulting modified electrode was applied to the selective
voltammetric detection of mercury(II) species after their accumulation at open circuit. The remarkable selectivity observed
between pH 4 and 7 was attributed to the intrinsic adsorption mechanism which involves a condensation reaction between mercury(II)
hydroxide and hydroxyl groups on the silica surface, leading to the formation of an inner-sphere-type surface complex. After
optimization with respect to the electrode composition, the detection medium, and the voltammetric scan mode, a linear response
was obtained in the concentration range between 2 × 10−7 M to 1 × 10−5 M, by applying anodic stripping square wave voltammetry. Various silica samples were used and their sorption behavior was
discussed in relation to their specific surface area and porosity. The effect of chloride and pH on the accumulation of mercury(II)
on silica was also investigated.
Received: 4 September 1999 / Accepted: 5 January 2000 相似文献
14.
M. A. Kabil S. E. Ghazy A. A. El-Asmy Y. E. Sherif 《Analytical and bioanalytical chemistry》1997,357(4):401-404
A sensitive and selective flotation procedure for the separation of microamounts of Co(II), Ni(II) and Cu(II) separately
or in admixture is described. The maximum separation rate (∼1) for 0.1 mmol/L of each analyte is achieved using 1 mmol/L of
both oleic acid (HOL) surfactant and 4-phenylthiosemicarbazide (HPTS) as a collector in the pH range 6–7. A method for the
simultaneous separation and microdetermination of the analytes is elaborated, based on adding excess HPTS and floating the
species with HOL at pH ∼6. The filtrate (which is clear brownish-yellow) obtained from the scum is used for the spectrophotometric
determination of Co(II) at 350 nm. The formation constants of 1:1 and 1:2 [Co(II):HPTS] species are 6.9×105 and 1.22×1010 L mol-1, respectively. Beer’s law is obeyed up to 9 μg/mL of Co(II) with a molar absorptivity of 1.15×104 L mol-1 cm-1. The precipitate in the scum layer is quantitatively collected, dissolved in aqua regia and aspirated directly into the flame
for the (AAS) determination of Ni and Cu. The procedure is successfully applied to some natural water samples. A mechanism
for the separation of the analytes is proposed.
Received: 23 January 1996/Revised: 1 April 1996/Accepted: 9 April 1996 相似文献
15.
Jadwiga Opydo 《Mikrochimica acta》2001,137(3-4):157-162
Necessary conditions were established for simultaneous nickel and cobalt determination in environmental samples, such as
oak wood and soil, based on cathodic adsorptive stripping voltammetry. Ni(II) and Co(II), complexed with dimethylglyoxime,
were determined using a hanging mercury drop electrode. Optimum conditions were found to be: accumulation time 90 s, accumulation
potential −0.80 V vs. SCE, supporting electrolyte 0.2 mol dm−3 ammonia-ammonium chloride buffer (pH = 9.4) + 0.05 mol dm−3 NaNO2 and dimethylglyoxime 2 × 10−4 mol dm−3. A linear current-concentration relationship was observed up to 7.51×10 −7 mol dm−3 for Ni(II) and 7.0 × 10−7 mol dm−3 for Co(II). Excess amounts of zinc(II) interfering with cobalt peaks were masked by complexation with EDTA. Wood and soils
were mineralized by applying a microwave digestion system, using the mixtures H2O2 + HNO3 or HNO3 + HF, respectively. The developed procedure was tested by analysing international reference materials (BCR 62 Olive Leaves
and GBW 08302 Tibet Soil). The developed procedure was used to determine pollution of oak stand with nickel and cobalt in
different regions of Poland.
Received August 10, 2000. Revision May 22, 2001. 相似文献
16.
The competitive sorption of Cu(II) and Eu(III) ions from aqueous solutions by olive-cake carbon, has been investigated by
potentiometry at pH 6, I=0.1 M NaClO4, 25°C and under normal atmospheric conditions. Evaluation of the experimental data supports the formation of inner-sphere
surface complexes and results in the calculation of the formation constant of the surface complexes ((=S–O)2Cu), which is found to amount log β
Cu=5.3±0.3. Addition of competing Eu(III) ions in the aqueous system leads to replacement of the Cu(II) by the competitor metal
ion. Evaluation of the potentiometric data obtained from competition experiments indicates an ion-exchange mechanism. The
formation constant of the Eu(III) species sorbed on olive cake carbon is found to be log β
Eu=5.1±0.5. Comparison of the complex formation constants of the olive-cake carbon with the corresponding complex formation
constants for of olive cake and humic acid with the two metal ions, indicates that the same type of active sites is responsible
for the metal ion complexation on the surface of the different types natural organic matter (e.g. olive-cake carbon, olive-cake
and humic acid). 相似文献
17.
A macroreticular poly(acrylic acid)-based resin with triazolethiol as the functional group has been synthesized. The stability of the resin in acidic media and the behaviour in sorption and desorption of various metal ions have been investigated and compared with those of the acylthiosemicarbazide resin which is an intermediate in synthesis of the triazolethiol resin. Both resins show high affinity for copper(II) silver, cadmium and mercury(II), and high selectivity for silver and mercury(II) at low pH (1–2), and even at pH 7 if EDTA is present. The triazolethiol resin sorbs metal ions faster than the acylthiosemicarbazide resin does and sorbs mercury(II) from high concentrations of acids and neutral salt solutions. This resin has been applied to the concentration of silver and mercury(II) from sea-water samples by column operation. 相似文献
18.
M. M. Antonijević R. P. Mihajlović B. V. Vukanović 《Journal of Solid State Electrochemistry》2001,5(1):29-35
The results obtained in potentiometric titrations of copper(II), mercury(II) and iron(III) with standard EDTA solutions are
presented. The titration of copper(II) at pH values in the range from 8.11 to 10.99 (ammonia buffer) and the titration of
mercury(II) and iron(III) at pH values from 3.59 to 5.65 (acetate buffer) were performed. The titration end-point (TEP) was
detected with an indicator electrode made from natural crystalline pyrite as an electrochemical sensor. The results obtained
in potentiometric titration with the pyrite electrode were compared with those obtained using a platinum electrode (Fe3+), a Cu ion selective electrode (Cu2+) and a Hg electrode (Hg2+). Accurate and reproducible results with good agreement were obtained, but higher potential changes at the TEP were obtained
using the pyrite electrode. In the course of the titration the potential was established within less than 1 min, whereas at
the TEP it was within about 2–3 min. The potential changes at the TEP were in the range from 60 to 200 mV per 0.1 ml EDTA,
according to the stability constant of the complex formed. The highest potential changes, ranging from 160 to 200 mV, were
obtained in the titration of iron(III) at pH 3.59. Reverse titration was also performed and accurate and reproducible results
were obtained. Moreover, titration of halogenide and thiocyanate with standard mercury(II) solutions, as well as cyanide with
silver(I) solution, were performed and accurate and reproducible results were again obtained.
Received: 20 February 1998 / Accepted: 19 November 1999 相似文献
19.
The electrochemical behavior of the ofloxacin–copper complex, Cu(II)L2, at a mercury electrode, and the interaction of DNA with the complex have been investigated. The experiments indicate that
the electrode reaction of Cu(II)L2 is an irreversible surface electrochemical reaction and that the reactant is of adsorbed character. In the presence of DNA,
the formation of the electrochemically non-active complexes Cu(II)L2-DNA, results in the decrease of the peak current of Cu(II)L2. Based on the electrochemical behavior of the Cu(II)L2 with DNA, binding by electrostatic interaction is suggested and a new method for determining nucleic acid is proposed. Under
the optimum conditions, the decrease of the peak current is in proportional to the concentration of nucleic acids in the range
from 3 × 10−8 to 3 × 10−6 g · mL−1 for calf thymus DNA, from 1.6 × 10−8 to 9.0 × 10−7 g · mL−1 for fish sperm DNA, and from 3.3 × 10−8 to 5.5 × 10−7 g · mL−1 for yeast RNA. The detection limits are 3.3 × 10−9, 6.7 × 10−9 and 8.0 × 10−9 g · mL−1, respectively. The method exhibits good recovery and high sensitivity in synthetic samples and in real samples. 相似文献
20.
Jadwiga Urbańska 《Journal of solution chemistry》2011,40(2):247-260
The dc polarographic method has been applied to study coordination equilibria between Mn(II) and oxalate ions in perchlorate
and sulfate solutions. The stoichiometries of complexes formed in solution and those reduced at a dropping mercury electrode
were established. The stability constants of the Mn(II) oxalate and sulfate complexes, as well as their diffusion coefficients,
were determined at a constant ionic strength 0.5 mol⋅L−1 and 25 °C. The stabilities of these Mn(II) complexes were compared with the corresponding complexes of other divalent metal
ions. The polarographic method was able to identify complexes that have not been established by other methods and to determine
their stability constants with high accuracy. 相似文献