Synthesis and Applications of Poly(Acrylphenylamidrazone-Phenyl-Hydrazide-Acylphenylhydrazine) Chelating Fiber for Preconcentration and Separation of Trae In(III), Zr(IV), Tl(I), V(V), Ga(III) and Ti(IV) from Solution Samples

 An ICP-OES method using a new poly (acrylphenylamidrazone-phenylhydrazide-acylphenylhydrazine) chelating fiber to preconcentrate and separate trace In(III), Zr(IV), Tl(I), V(V), Ga(III) and Ti(IV) ions from solution samples has been established. The new chelating fiber was synthesized using polyacrylonitrile fiber as a starting material and the structure of the chelating fiber was determined by FT infrared spectrometry. The acidity, adsorption rate, re-use, capacity and interference on the adsorption of ions on the chelating fiber as well as the conditions of desorption of these ions from the chelating fiber were investigated by means of inductively coupled plasma optical emission spectrometry (ICP-OES). The results show that the relative standard deviations for the determination of 10 ng/ml In, Tl, Ga and 1 ng/ml Zr, V, Ti were lower than 2.5%. The results obtained for these ions in real solution samples by this method were basically in agreement with the given values with average errors of less than 4%. Received November 29, 2000. Revision May 22, 2001.     

Efficiency and mechanism of new poly(acryl-phenylamidrazone phenylhydrazide) chelating fiber for adsorbing trace Ga, In, Bi, V and Ti from solution

A new po1y(acrylphenylamidrazone phenylhydrazide) chelating fiber is synthesized from polyacrylonitrile fiber and used for preconcentration and separation of trace Ga(III), In(III), Bi(III), V(V) and Ti(IV) from solution (5–50 ng ml⁻¹ Ti(IV) or V(V) and 50–500 ng ml⁻¹ Ga(III), In (III) or Bi(III) in 1000–100 ml of solution can be enriched quantitatively by 0.15 g of fiber at a 4 ml min⁻¹ flow rate in the pH range 5–7 with recoveries >95%). These ions can be desorbed quantitatively with 20 ml of 4 M hydrochloric acid at 2 ml min⁻¹ from the fiber column. When the fiber which had been treated with concentrated hydrochloric acid and washed with distilled water until neutral was reused eight times, the recoveries of the above ions by enrichment were still >95%. Two-hundred-fold to 10 000-fold excesses of Cu(II), Zn(II), Ca(II), Mn(II), Cr(III), Fe(III), Ba(II) and Al(III) caused little interference in the determination of these ions by inductively coupled plasma-atomic emission spectrometers (ICP-AES). The relative standard deviations for enrichment and determination of 50 ng ml⁻¹ Ga, In or Bi and 10 ng ml⁻¹ V or Ti are in the range 1.2–2.7%. The contents of these ions in real solution samples determined by this method were in agreement with the certified values of the samples with average errors <3.7%.     

Synthesis and Efficiency of an Epoxy-Urea Chelating Resin for Preconcentrating and Separating Trace Bi,In, Sn,Zr, V And Ti From Solution Samples

Abstract

A new epoxy-urea chelating resin was synthesized from epoxy resin and used for the preconcentration and separation of trace Bi(III), In(III), Sn(IV), Zr(IV), V(V) and Ti(IV) ions from solution samples. The analyzed ions can be enriched at pH 5 at a flow rate of 1–4 ml/min, and can be also desorbed with 10 mL of 2 M HCl +0.1g NH₄F solution from the resin column, with recoveries over 97%. The chelating resin reused 6 times can still adsorb quantitatively the Bi, In, Sn, Zr, V and Ti ions, and eighty to thousand-fold excesses of Ca(II), Mg(II), Cu(II), Zn(II), Al(III), Sb(III), Ni(II), Mn(II) and Fe(III) cause little interference with the enrichment and determination of these ions. The RSDs of the proposed method for the determination of 500–50 ng/ml Bi, In and Sn, 50–5.0 ng/ml Zr, V and Ti were in the range of 0.4 ～ 4.0%, the enrichment factor of the resin for the ions is in the range of 10–100. The recoveries of added standard in waste water are between 96% and 100%, and the concentration of each ion in alloy steel sample determined by the method is in good agreement with the reference value analyzed by a steel plant with average error <2.8%.     

Chemometrics-assisted spectrophotometric methods for simultaneous determination and complexation study of Fe(III), Al(III) and V(V) with morin in micellar media

Evolutionary factor analysis (EFA) and rank annihilation factor analysis (RAFA) were applied to resolve the two-way equilibrium spectrophotometric data belonging to the complexes of Fe(III), Al(III) and V(V) with morin (3,5,7,20,40-penta hydroxy flavone) as chelating agent in triton X-100 micellar media. Then, partial least square regression combined with genetic algorithm for wavelength selection (GA-PLS) was used for simultaneous determination of the metal ions. The parameters controlling behavior of the system were investigated and optimum conditions were selected. The predictive abilities of partial least squares regression (PLS) and genetic algorithm-partial least squares regression (GA-PLS) were examined in simultaneous determination of ternary mixtures of metal ions over the concentration range of 17.0-170.0ngml(-1), 25.0-180.0ngml(-1) and 40.0-325.0ngml(-1) for Fe(III), Al(III) and V(V), respectively. The relative standard errors for prediction of the ions in synthetic mixtures were lower than 5% and the mean recoveries in the tap water spiked samples were 104.2 and 101.7% for PLS and GA-PLS, respectively.     

Synthesis of spherical macroporous epoxy-dicyandiamide chelating resin and properties of concentration and separation of trace metal ions from samples

A novel spherical macroporous epoxy-dicyandiamide chelating resin is synthesized simply and rapidly from epoxy resin and use for the preconcentration and separation of trace Ga(III), In(III), Bi(III), Sn(IV), Pb(II), V(V) and Ti(IV) ions from solution samples. The analyzed ions can be quantitatively concentrated by the resin at flow rate of 3.0 ml min(-1) at pH 3, and can also be desorbed with 10 ml of 4 M HCl+0.2 g thiourea from the resin column with recoveries of 97-100%. The chelating resin is reused for eight times, the recoveries of these ions are still over 92%, and a 100-1000 times of excess of Fe(III), Al(III),Ca(II), Mg(III), Ni(II), Mn(II), Co(II), Cu(II), Zn(II), and Cd(II) cause no interference in the determination of these ions by inductively-coupled plasma atomic emission spectrometry. The capacities of the resin for the analytes are in the range of 0.66-4.20 mmol g(-1). The results show the relative standard deviation for the determination of 50.0 ng ml(-1) Ga(III), In(III), Bi(III), Sn(IV) and Pb(II), 5.0 ng ml(-1) V(V) and Ti(IV) are in the range of 1.2-4.0%. The recoveries of a standard added in real solution samples are between 96 and 100%, and the concentration of each ion in mineral sample detected by the method is in good agreement with the certified value.     

ICP-OES determination of traces of Ru, Au, V and Ti preconcentrated and separated by a new poly(epoxy-melamine) chelating resin from solutions

A new poly(epoxy-melamine) chelating resin is synthesized from epoxy resin and used for the preconcentration and separation of traces of Ru(III), Au(III), V(V) and Ti(IV) ions from sample solutions. The ions analyzed can be quantitatively enriched by the resin at a flow-rate of 2 mL/min at pH 4, and quantitatively desorbed with 10 mL of 1 mol/L HCl + 0.2 g CS(NH₂)₂ at a flow-rate of 1 mL/min with recoveries of over 97%. The chelating resin can be reused 7 times without obvious loss of efficiency. Thousand-fold excesses of coexistent ions caused little interference during the enrichment and determination steps. The RSDs for the determination of 50 ng/mL Ru(III) and Au(III), 5.0 ng/mL V(V) and Ti(IV) were in the range of 1.5–4.5%. The recoveries of added standards in a real sample solution are between 96% and 100%, and the results for the ions analyzed in a nickel alloy sample are in good agreement with their reported values.     

Properties and applications of polyacrylacylisothiourea chelating fiber for preconcentration and separation of trace titanium, vanadium and bismuth

An ICP-OES method using a new poly-acrylacylisothiourea chelating fiber to preconcentrate and separate trace Ti(IV), V(V) and Bi(III) ions from solution samples is established. The results show that 5–25 ng/ml of Ti or V and 50–250 ng/ml of Bi ions in 200–1000 ml of solution can be enriched quantitatively by 0.05 g of the fiber at pH 3 with recoveries over 97%. These ions can be desorbed quantitatively with 10 ml of 4M HC1O₄. 100- to 1000-fold excesses of Fe(III), Al(III), Ca(II), Mg(II), Cu(II), Ni(II) and Mn(II) ions cause little interference. The chelating fiber stored for about 2 years can still be used repeatedly for preconcentration and separation of trace Ti, V and Bi ions from solution with above 95% recovery. The RSDs for enrichment and determination of 5 ng/ml of Ti or V and 50 ng/ml of Bi are in the range 2.5–2.8%. The recoveries of added standard in real waste waters and mineral samples are between 96 and 100%, and the concentration found for each ion in the mineral sample was in good agreement with that measured by ETAAS.     

Synthesis and applications of poly(acryl<Emphasis Type="Italic">p</Emphasis>-aminobenzenesulfonamideamidine-<Emphasis Type="Italic">p</Emphasis>-aminobenzenesulfonylamide) chelating fiber for pre-concentrating and separating trace Bi(III), Hg(III), Au(III) and Pd(IV) from solution samples

Poly(acrylp-aminobenzenesulfonamideamidine-p-aminobenzenesulfonylamide) chelating fiber containing "S", "N", and "O" elements was synthesized from polyacrylonitrile fiber and p-aminobenzene sulfonamide and used to enrich and separate trace Bi(III), Hg(III), Au(III), and Pd(IV) ions from wastewater and ore sample solution. The enrichment acidity, flow rate, elution conditions, reuse, interference ions, saturated adsorption capacity, constant of adsorption rate, analytical accuracy, and actual samples on chelating fiber were investigated by means of inductively coupled plasma optical emission spectrometry (ICP-OES) with satisfactory results. Solutions of 100 ng mL^–1 of Bi(III), Hg(III), Au(III), and Pd(IV) ions can be enriched quantitatively by this chelating fiber at a rate of 1.0 mL min^–1 at pH 4 and desorbed quantitatively with 20 mL of 0.25 M HCl and 2% CS(NH₂)₂ solution at 50 °C (with recovery 97%). When the chelating fiber was reused for 20 times, the recoveries of the analyzed ions enriched by the fiber were still over 95% (except for Hg(III)). One thousand-fold excesses of Mn²⁺, Ca²⁺, Zn²⁺, Mg²⁺, Fe³⁺, Cu²⁺, Ni²⁺, Al³⁺, and Ba²⁺ ions and thousands-fold excesses of Na⁺ and K⁺ cause little interference in the pre-concentration and determination of the analyzed ions. The saturated adsorption capacity of Bi(III), Hg(III), Au(III), and Pd(IV) was 4.850×10^–4, 3.235×10^–4, 2.807×10^–4, and 3.386×10^–4 mol g^–1, respectively. The constants of adsorption rate were 0.409 min^–1 for Bi, 0.122 min^–1 for Hg, 0.039 min^–1 for Au, and 0.080 min^–1 for Pd. The relative standard deviations (RSDs) for the enrichment and determination of 10 ng mL^–1 Bi(III), Hg(III), Au(III), and Pd(IV) were lower than 2.3%. The results obtained for these ions in actual samples by this method were basically in agreement with the given values with average errors of less than 1.0%. FT-IR spectra shows that the existence of –SO₂–Ar, –H₂N–Ar, O=C–NH–, HN=C–NH–, and –HN–SO₂ functional groups are verified in the chelating fiber. From the FT-IR spectroscopy, we can see that Hg(III), Au(III), and Pd(IV) are mainly combined with nitrogen and sulfur (or oxygen), and Bi(III) is mainly combined with nitrogen (or oxygen) of the groups to form a chelating complex.     

ICP-OES determination of traces of Ru, Au, V and Ti preconcentrated and separated by a new poly(epoxy-melamine) chelating resin from solutions

A new poly(epoxy-melamine) chelating resin is synthesized from epoxy resin and used for the preconcentration and separation of traces of Ru(III), Au(III), V(V) and Ti(IV) ions from sample solutions. The ions analyzed can be quantitatively enriched by the resin at a flow-rate of 2 mL/min at pH 4, and quantitatively desorbed with 10 mL of 1 mol/L HCl + 0.2 g CS(NH₂)₂ at a flow-rate of 1 mL/min with recoveries of over 97%. The chelating resin can be reused 7 times without obvious loss of efficiency. Thousand-fold excesses of coexistent ions caused little interference during the enrichment and determination steps. The RSDs for the determination of 50 ng/mL Ru(III) and Au(III), 5.0 ng/mL V(V) and Ti(IV) were in the range of 1.5–4.5%. The recoveries of added standards in a real sample solution are between 96% and 100%, and the results for the ions analyzed in a nickel alloy sample are in good agreement with their reported values. Received: 12 May 1997 / Revised: 1 September 1997 / Accepted: 9 October 1997     

Application of an imidazoline group-containing chelating fiber for the determination of trace noble metals in superhigh-temperature alloys

An imidazoline group-containing chelating fiber was prepared by means of the reaction of nitrile groups with ethylenediamine in an hydrazine-modified polyacrylonitrile fiber. The adsorption properties of the chelating fiber for Au(III), Pd(II), Pt(IV), Ir(IV), Os(IV), Rh(III) and Ru(IV) ions, such as binding capacity, distribution coefficient, sorptive rate and quantitative elution of Au(III), Pd(II) and Pt(IV) ions were investigated. The imidazoline group-containing chelating fiber possessed high binding capacities and good adsorption kinetic properties, exhibited high affinity for noble metals in 0.1-1.0 mol/L HCl and could be efficiently re-used. After the separation of trace Au(III), Pd(II) and Pt(IV) ions from a matrix using the chelating fiber, these ions could be determined by ICP-AES with satisfactory results, and the relative standard deviation for Au(III), Pd(II) and Pt(IV) ions was less than 6%.     

Synthesis of polyacrylaminoimidazole chelating fiber and properties of concentration and separation of trace Au, Hg and Pd from samples

A novel polyacrylaminoimidazole chelating fiber is synthesized simply and rapidly from nitrilon (an acrylonitrile-based synthetic fiber) and used for the preconcentration and separation of trace Au(III), Hg(II) and Pd(IV) ions from solution samples. The analyzed ions can be quantitatively concentrated by the fiber up to a flow rate of 15.0 mlmin(-1) at pH 3 and can also be desorbed with 15 ml of 4 M HCl+3% thiourea from the fiber column, with recoveries of 96.5-100%. The chelating fiber is reused ten times; the recoveries of these ions are still over 92%, and 100-1000 times of excess of Fe(III), Al(III), Ca(II), Mg(II), Ni(II), Mn(II), Cu(II), Zn(II) and Cd(II) causes no interference in the determination of these ions by inductively coupled plasma atomic emission spectrometry. The capacities of the fiber for the analytes are in the range of 1.56-2.92 mmolg(-1). The results show that the relative standard deviations for the determination of 50.0 ngml(-1) each of Au(III), Hg(IV) and Pd(IV) are in the range of 0.7-2.1%. The recoveries of a standard added in real solution samples are between 97 and 99%, and the concentration of each ion in powder sample detected by the method is in good agreement with the certified value.     

Sulfonylcalix[4]arenetetrasulfonate as pre-column chelating reagent for selective determination of aluminum(III), iron(III), and titanium(IV) by ion-pair reversed-phase high-performance liquid chromatography with spectrophotometric detection

Sulfonylcalix[4]arenetetrasulfonate (SO₂CAS) has been examined as a pre-column chelating reagent for ultratrace determination of metal ions by ion-pair reversed-phase high-performance liquid chromatography with spectrophotometric detection. Metal ions were converted into the SO₂CAS chelates in an acetic buffer solution (pH 4.7). The chelates were injected onto a n-octadecylsilanized silica-type Chromolith™ Performance RP-18e column and were eluted using a methanol (50 wt.%)-water eluent (pH 5.6) containing tetra-n-butylammonium bromide (7.0 mmol kg⁻¹), acetate buffer (5.0 mmol kg⁻¹), and disodium ethylendiamine-N,N,N′,N′-tetraacetate (0.10 mmol kg⁻¹). Under the conditions used, Al(III), Fe(III), and Ti(IV) were selectively detected among 21 kinds of metal ions [Al(III), Ba(II), Be(II), Ca(II), Cd(II), Co(II), Cr(III), Cu(II), Fe(III), Ga(III), Hf(IV), In(III), Mg(II), Mn(II), Mo(VI), Ni(II), Pb(II), Ti(IV), V(V), Zn(II), and Zr(IV)]. The detection limits on a 3σ blank basis were 8.8 nmol dm⁻³ (0.24 ng cm⁻³) for Al(III), 7.6 nmol dm⁻³ (0.42 ng cm⁻³) for Fe(III), and 17 nmol dm⁻³ (0.80 ng cm⁻³) for Ti(IV). The practical applicability of the proposed method was checked using river and tap water samples.     

Application of an imidazoline group-containing chelating fiber for the determination of trace noble metals in superhigh-temperature alloys

An imidazoline group-containing chelating fiber was prepared by means of the reaction of nitrile groups with ethylenediamine in an hydrazine-modified polyacrylonitrile fiber. The adsorption properties of the chelating fiber for Au(III), Pd(II), Pt(IV), Ir(IV), Os(IV), Rh(III) and Ru(IV) ions, such as binding capacity, distribution coefficient, sorptive rate and quantitative elution of Au(III), Pd(II) and Pt(IV) ions were investigated. The imidazoline group-containing chelating fiber possessed high binding capacities and good adsorption kinetic properties, exhibited high affinity for noble metals in 0.1–1.0 mol/L HCl and could be efficiently re-used. After the separation of trace Au(III), Pd(II) and Pt(IV) ions from a matrix using the chelating fiber, these ions could be determined by ICP-AES with satisfactory results, and the relative standard deviation for Au(III), Pd(II) and Pt(IV) ions was less than 6%. Received: 5 July 1999 / Revised: 4 October 1999 / Accepted: 4 October 1999     

Ion flotation behaviour of thirty-one metal ions in mixed hydrochloric/nitric acid solutions

The ion flotation of 31 metal ions in hydrochloric/nitric acid solution with the cationic surfactant cetylpyridinium chloride was investigated. A 25-ml portion of 0.27-2.87 x 10(-4)M metal ion and 1.8-6.0 x 10(-4)M cetylpyridinium chloride solution in 0.17-3.4M acid mixture ([HCl]:[HNO(3)] = 2.4:1) was subjected to flotation in a cell, 22.5 cm high and 4.0 cm in diameter, for 5 min, with nitrogen bubbles. Ir(IV), Pt(IV), Ge(IV), Sn(IV), Bi(III), Au(III), Tl(III), Pd(II) and Sn(II) were floated from solution in 95-100% yield; Ru(III), Rh(III), Ir(III), Hg(II), Ag(I) and Tl(I) were partly floated, while Cr(VI), Ti(IV), Zr(IV), Ga(III), In(III), Fe(III), Sb(III), Al(III), Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), CD(II) and Pb(II) were floated with less than 20% yield. The flotation behaviour of these metal ions in the mixed acid system was compared with that in hydrochloric acid. The flotation is more efficient in the mixed acid system.     

Separation and determination of trace amounts of beryllium(II), aluminium(III) and chromium(III) with chromotrope 2C chelates by RP-HPLC

A reversed-phase high-performance liquid chromatographic separation and determination of beryllium(II), aluminium(III) and chromium(III) with chromotrope 2C chelates on a C18-bonded stationary phase is reported. Methanol-water (45:55 v/v) containing 6 x 10(-3)M tetra-n-butylammonium bromide (TBAB) and 2 x 10(-2)M acetate buffer solution (pH 6.0) as mobile phase and with spectrophotometric detection at 530 nm was applied. The method has high sensitivity, the detection limits being 0.2 ppb for beryllium(I), 1 ppb for aluminium(III) and 2 ppb for chromium(III). Under the optimum conditions, most other metal ions did not interfere, e.g. up to 2 mg of Hg(II), Sn(II, IV), Pb(II), Bi(III), Ag(I), Zn(II), Cd(II), Cu(II), 1.5 mg of Fe(II), Co(II), Ni(II), 1.2 mg of Ca(II), Mg(II), Sr(II), Ba(II), 1 mg of Ga(III), In(III), 0.5 mg of Fe(III), 1 mg of Ga(III), In(III), 0.5 mg of Fe(III), 0.4 mg of Th(IV), Zr(IV). The method can be applied to the simultaneous determination of trace amounts of beryllium(II), aluminium(III) and chromium(III), in water, rice, flour and human hair samples.     

Synthesis of poly(N-aminoethyl)acrylamide chelating fiber and properties of concentration and separation of noble metal ions from samples

A new kind of poly(N-aminoethyl)acrylamide chelating fiber was synthesized from nitrilon (an acrylonitrile-based synthetic fiber) and used for the concentration and separation of traces of noble metal ions from solution. The results showed that 16-80 ng ml (1) of Au(III), Pt(IV), Pd(IV), Ir(IV), Ru(III) and Rh(III) can be quantitatively concentrated by the fiber up to a flow rate of 20 ml min (-1) at pH 3, and can be desorbed quantitatively with an eluting agent from the fiber column with recoveries of 96-100%. For a fiber reused 10 times, the recoveries of these ions were still over 94%, and a 100-1000 times excess of Fe(III), Al(III), Ca(II), Mg(II), Ni(II), Co(II), Cu(II) and Zn(II) caused no interference in the determination of these ions by inductively-coupled plasma atomic emission spectrometry. The capacities of the fiber for the analytes were in the range 0.80-2.62 mol g(-1), The relative standard deviation of the method was between 0.02% and 2.6%. Recoveries of a standard added to a real sample were 96.8-99.2%. The average error for the analysis by this method for a powder sample was 3.5%. The IR spectra of the analyte-bearing fiber showed that these ions coordinated to nitrogen sites in the fiber.     

Sorption behaviour of lanthanum(III), neodymium(III), terbium(III), thorium(IV) and uranium(VI) on Amberlite XAD-4 resin functionalized with bicine ligands

The complexing properties (capacity, pH effect, breakthrough curve) of a chelating resin, containing bicine ligands, were investigated for La(III), Nd(III), Tb(III), Th(IV) and U(VI). Trace amounts of these metal ions were quantitatively retained on the resin and recovered by eluting with 1 M hydrochloric acid. The capacity of the resin for La(III), Nd(III), Tb(III), Th(IV) and U(VI) was found to be 0.35, 0.40, 0.42, 0.25 and 0.38 mmol g(-1), respectively. Separation of U(VI) and Th(IV) from Ni(II), Zn(II), Co(II) and Cu(II) in a synthetic solution was carried out.     

Consecutive thin-layer chromatographic separation of Zr(IV), Hf(IV) and many other ions on silica gel in nitric acid-hydrogen peroxide media

The thin-layer chromatographic (TLC) behaviour of 64 ions including Zr(IV) and Hf(IV) has been surveyed on systems composed of silica gel and of nitric acid and nitric acid-hydrogen peroxide media. In the 0.5 mol 1(-1) HNO(3)-3% (w/v) H(2)O(2) solution, only Hf(IV) adsorbed very strongly, whereas Zr(IV) and many other ions showed no or weak adsorption. Stepwise development with diluted nitric acid and subsequently with nitric acid-hydrogen peroxide solution allowed the consecutive separation of three-component mixtures consisting of Zr(IV), Hf(IV) and one of many other accompanying elements, such as Mo(VI), Nb(V), Th(IV), Ti(IV), U(VI) and rare earths(III), to be conducted simply and effectively.     

Zwitterion-functionalized polymer microspheres as a sorbent for solid phase extraction of trace levels of V(V), Cr(III), As(III), Sn(IV), Sb(III) and Hg(II) prior to their determination by ICP-MS

This paper describes the preparation of zwitterion-functionalized polymer microspheres (ZPMs) and their application to simultaneous enrichment of V(V), Cr(III), As(III), Sn(IV), Sb(III) and Hg(II) from environmental water samples. The ZPMs were prepared by emulsion copolymerization of ethyl methacrylate, 2-diethylaminoethyl methacrylate and triethylene glycol dimethyl acrylate followed by modification with 1,3-propanesultone. The components were analyzed by elemental analyses as well as Fourier transform infrared spectroscopy, and the structures were characterized by scanning electron microscopy and transmission electron microscopy. The ZPMs were packed into a mini-column for on-line solid-phase extraction (SPE) of the above metal ions. Following extraction with 40 mM NH₄NO₃ and 0.5 M HNO₃ solution, the ions were quantified by ICP-MS. Under the optimized conditions, the enrichment factors (from a 40 mL sample) are up to 60 for the ions V(V), As(III), Sb(III) and Hg(II), and 55 for Cr(III) and Sn(IV). The detection limits are 1.2, 3.4, 1.0, 3.7, 2.1 and 1.6 ng L^?1 for V(V), Cr(III), As(III), Sn(IV), Sb(III) and Hg(II), respectively, and the relative standard deviations (RSDs) are below 5.2%. The feasibility and accuracy of the method were validated by successfully analyzing six certified reference materials as well as lake, well and river waters.

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Graphical abstract Zwitterion-functionalized polymer microspheres (ZPMs) were prepared and packed into a mini-column for on-line solid-phase extraction (SPE) via pump 1. Then V(V), Cr(III), As(III), Sn(IV), Sb(III) and Hg(II) ions in environmental waters were eluted and submitted to ICP-MS via pump 2.

     

Selective and quantitative separation of zinc and lead from other elements by cation-exchange chromatography in hydrohalic acid-acetone solutions

Zinc and lead can be separated from Cd, Bi(III), In and V(V) by eluting these elements with 0.2M hydrochloric acid in 60% acetone from a column of AG50W-X8 cation-exchange resin, zinc and lead being retained. Mercury(II), Tl(III), As(III), Au(III), Sn(IV), Mo(VI), W(VI) and the platinum metals have not been investigated quantitatively, but from their distribution coefficients, should also be eluted. Vanadium(V), Mo(VI) and W(VI) require the presence of hydrogen peroxide. Zinc and lead can be eluted with 0.5M hydrochloric acid in 60% acetone or 0.5M hydrobromic acid in 65% acetone and determined by AAS; the alkali and alkaline-earth metal ions, Mn(II), Co, Ni, Cu(II), Fe(III), Al, Ga, Cr(III), Ti(IV), Zr, Hf, Th, Sc, Y, La and the lanthanides are retained on the column, except for a small fraction of copper eluted with zinc and lead. Separations are sharp and quantitative. The method has successfully been applied to determination of zinc and lead in three silicate rocks and a sediment.