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1.
研发了一种自动固相萃取系统,用于分离地质样品中铁同位素。系统有4个并行通道,可以一次处理4个样品。对于这4个样品,一次处理过程仅需24 min。选用AG1-X8阴离子交换树脂对花岗岩样品(GBW07103)中的铁进行萃取。在萃取过程中,当盐酸浓度大于6 mol/L时,铁形成络阴离子并被吸附在AG1-X8阴离子交换树脂上,其余阳离子被洗脱出来。用浓度为8 mol/L的HNO 3和H 2O洗脱铁,铁的洗脱体积为4 mL,铁可以被定量回收,回收率达到96.0%~107%。消除了测试过程中的基体影响,提高了样品处理效率,减少了人为污染风险,是一个多元化样品处理工具。  相似文献   

2.
A procedure for recovery of 65Zn from acidic Ga-rich solutions generated in 68Ge production process was developed and implemented in a “hot cell” environment. A one step simple separation was carried out on anion exchange column filled with Biorad AG1-X8 resin. With 65Zn recovery yields of more than 95% this procedure is currently routinely used at Brookhaven Linac Isotope Producer.  相似文献   

3.
Literature data on distribution ratios (Dw) of Np(V) and Pa(V) for the AG1-X8 resin are scarce whereas those related on resin capacity factors (k′) values for TEVA, TRU and U/TEVA resins are absent. Therefore, batch extraction experiments for Pa(V) and Np(V) from HCl and HNO3 media were realized, at tracer scale, with AG1-X8 and EIChroM resins (TEVA, TRU and U/TEVA). Based on the new Dw and k′ values obtained in this study, a new protocol for Pa/Np separation has been developed leading to a better separation factor of 105 and a chemical yield of 97 ± 3% and 99 ± 1% for Pa and Np, respectively. A separation of 231Pa from uranium matrix was successfully tested.  相似文献   

4.
Miyazaki Y  Nakai M 《Talanta》2011,85(4):1798-1804
Protonation and ion exchange equilibria of weak base anion-exchange resins, in which tertiary amine moieties were introduced as a functional group, were investigated by applying NMR spectroscopy to species adsorbed into the resins. 31P NMR signals of the phosphinate ion in the resin phases shifted to a lower field due to the influence of protonation of the tertiary amine groups of the resins in the pH range of 4-10. Protonation constants of the tertiary amine groups in styrene-divinylbenzene (DVB)-based resins were estimated to be KH = 106.4 for Amberlite IRA96 and 106.5 for DIAION WA30 by the 31P NMR method using the phosphinate ion as a probe species. In addition to the low field shift caused by the protonation of the tertiary amine moieties, another low field shift was observed for the phosphinate ion in acrylic acid-DVB-based resins at a rather high pH. This shift should be due to an unexpected deprotonation in the acrylic resin: a tautomerism accompanying the proton release from the amide form to the imide one in the functional group, thus, the resin could exhibit a cation exchange property at the high pH. Protonation constants of the tertiary amine moieties in the acrylic resins were estimated to be 108.8 for DIAION WA10, 109.0 for Amberlite IRA67 and 109.3 for Bio-Rad AG 4-X4 on the basis of the Henderson-Hasselbalch equation using the resin phase pH estimated by the 133Cs and 1H NMR signal intensities.  相似文献   

5.
Systematic information of exchange behavior of Ge(IV) and Ga(III) in varying oxalic acid (0.05M and 0.25M) and sulphuric acid (0.005M-2M range) mixtures is presented. These findings were used to develop a separation involving 68Ge from a Ga2O target material. A method based on acid dissolution of the target and chromatography on an anion exchange resin (Bio-RadÒ AG1-X8) was developed. The separated 68Ge has high radionuclidic purity and an acceptable chemical purity.  相似文献   

6.
Summary The dependence of the chloride distribution coefficient on the co-ion of solutions of different alkali fluorides, MF, up to 11M is tested on the strongly basic anion-exchange resin AG1-X10. Under the same experimental conditions the distribution coefficient decreases in the following order for M+: Na+>K+>Rb+>Cs+. This can be explained by the different co-ion-chloride interactions. The consequence of this interaction for a chromatographic separation of chloride is shown with 5M KF and CsF solutions, used as eluants. Depending on the fluoride concentration, the distribution coefficient passes through a minimum value to increase again at higher electrolyte concentration. The non-exchange electrolyte in the resin phase is responsible for this effect. In addition, the bromide and the iodide distribution coefficients up to 10M KF solutions are determined. One results is that the selectivity coefficient between halide ions increases at higher electrolyte concentrations.  相似文献   

7.
The 109Cd radionuclide was produced in the cyclotron via natAg(p,n)109Cd reaction. The radiochemical separation of 109Cd from silver and non-isotopic impurities comprised of two stages. The optimum conditions of the 109Cd separation methods were: Ag precipitation with 0.015 M HCl and Cu and 65Zn by use of 0.015 M HCl on AG1-X8 strong anion-exchange resin. Chemical and radionuclidic purity of 109Cd were measured by ICP-AES and gamma-ray spectrometry respectively. Recovery yield and radionuclidic purity were obtained 99.7% and 99%, respectively.  相似文献   

8.
A radiochemical purification procedure was developed for the separation of enriched cadmium (111Cd and 112Cd) from natural copper that used as backing; and was based upon the chromatographic adsorption. The separation of copper from cadmium was studied in this work. The ions were selectively separated from aqueous solution. Ion-exchange chromatography was employed as a column (1.5 cm i.d. and 15 cm length) with AG1-X8 resin (chloride form, 100–200 mesh) and a flow rate of 1–2 ml/min throughout the separation. 6 M HCl media was used for the adsorption of Cd and Cu on the resin. Then, Cu was eluted by 2 M HCl and Cd by 100 ml 0.5 M HNO3. The amount of Cu and Cd ions in the final solution (0.5 M HNO3) were measured by pulse polarographic method and the concentration of Cu was found to be <0.1 ppm. The Cd was quantitatively recovered and the recovery yield from ion-exchange chromatography was greater than 96 %.  相似文献   

9.
Production cross sections of residues with mass near to that of the target were measured in 12C and 16O induced reactions on Rh at an incident energy of 400 MeV. An ion-exchange method has been developed for the separation of Rh, Pd and Ag nuclides from all other produced activities. Rh and Ag nuclides were separated from elements such as Pd, Ru, and Tc, amongst others, on an AG1-X8 anion exchange resin in 6M HCl. The Ag nuclides were then removed from the effluent using a precipitation technique so that only Rh remained in the final solution. The Pd was afterwards separated from Ru and Tc by eluting it from the resin with 5% ammonia solution. This procedure made it possible to accurately measure production cross sections for 103mRh and 103Pd. Cross sections for the production of various other observed residues are also presented. The results are consistent with an enhanced isobaric yield in the near-target mass region. The radiochemical separation technique is also suitable for the routine production of Pd and Rh nuclides, e.g., 103Pd and 101mRh, in proton-induced reactions on Rh targets  相似文献   

10.
Many biological samples (urines and faeces) have been analyzed by means of chromatographic extraction columns, utilizing two different resins (AG 1-X2 resin chloride and TRU), in order to detect the possible internal contamination of 239+240Pu and 241Am for some workers of a reprocessing nuclear plant in the decommissioning phase. The results obtained show on one hand the great suitability of the first resin for the determination of plutonium, and on the other, the great selectivity of the second one for the determination of americium.  相似文献   

11.
A new procedure for the preconcentration of p.p.b. concentrations of chromate from aqueous solutions has been developed. Water samples containing chromate are acidified to pH 5 and passed through an anion-exchange resin bed (AG1-X4, 100–200 mesh. Cl? form) in ascending flow, so that the chromate is adsorbed in a narrow zone at the lower end of the resin bed. The chromate is eluted rapidly with small volumes of an acidic reductant solution which reacts with chromate on the column to form chromium(III) during the actual elution step, thus producing very high concentration factors.  相似文献   

12.
A radiochemical separation method was developed for the separation of 109Cd from a nat.Ag target (6.6 g, pressed into a 19 mm disc). The method comprised of two stages. In the first stage, after dissolution of the target in nitric acid, silver was separated from Cd by precipitation into the metallic form using 20 g of Cu turnings for the reduction of Ag+ ions. In the second stage, 109Cd in the filtrate, that contained trace amount of silver and substantial quantity of Cu(I), was purified by use of a Bio-Rad AG1-X10 anion-exchange resin. The ion-exchange chromatography employed a column with (1.6 cm i.d. and 4 cm length) with a flow rate of 2 ml/min throughout the separation. 109Cd was quantitatively recovered from the first stage and the recovery yield from the ion-exchange chromatography was greater than 96%. 2M HCl containing H2O2 was used for the adsorption of 109Cd and elution of Cu. 109Cd was eluted by 50 ml 1M HNO3. The concentrations of stable isotopes of Ag and Cu in the final solution (5 ml 0.05M HCl) were measured by an ICP-OES method and found to be <1 ppm.  相似文献   

13.
The sorption of 1,8-dihydroxy-2-(pyrazol-5-ylazo)-naphthalene-3,6-disulfonic acid onto the anion exchange resins Dowex 1-X8 and Dowex 2-X8 from aqueous solutions of between pH 1 and 10 was studied spectrophotometrically. Conditions for obtaining modified sorbents with a given capacity for the azo compound were investigated. The absorption and reflectance spectra of the sorbed dye were traced. The immobilized reagent retained chromic characteristics similar to those it had in solution. The mechanism of sorption was investigated under static conditions in the temperature range of 0 to 25°C by following the amount of sorbed dye as a function of contact time. The sorption was a first-order process in all cases. Pore diffusion was found to be the rate-limiting step in the sorption process. Diffusion coefficient values of from 6.0 × 10–7 to 7.4 × 10–7 cm2/s were calculated from the experimental results. The values of the activation energy of PACA sorption were found to be –8.56 and –8.05 kJ/mol for Dowex 1-X8 and Dowex 2-X8, respectively.  相似文献   

14.
The behaviour of Mo and some other elements on Ag MP-1 in alkaline medium was investigated. Equilibrium distribution coefficients, Kd, are presented for Mo on the anion exchangers AG 1-X2, AG 1-X4, AG 1-X8 and AG MP-1, and for some elements on AG MP-1 in alkaline medium. An anion exchange chromatographic separation of Mo from some of these elements is described and some results obtained with this method are reported.  相似文献   

15.
The retention of gallium(III) on Dowex 50-X8 resin in 0.6 M HCl-dioxan media was studied as a function of the dioxan content. The ion-exchange in complexing medium (HC1) and in non-complexing medium (H2SO4) was studied; the determination of the distribution coefficients indicated the reactions occurring in the different media. Solvent uptake by Dowex 50-X8 (H+ and Ga(III) forms) from 0.6 M HCl-dioxan mixtures and the solvent composition in the resin were determined. The influence of the weak dielectric constant of dioxan proved to be most important; however, specific solvation phenomena were evident.  相似文献   

16.
In spite of the development of new measurement techniques in recent years, the rapid and accurate speciation of thallium in environmental aqueous samples remains a challenge. In this context, a novel method of solid phase extraction (SPE), involving the anion exchange resin AG1-X8, is proposed to separate Tl(I) and Tl(III). In the presence of diethylene triamine pentacetate acid (DTPA), Tl(III) and Tl(I) can be separated by selective adsorption of Tl(III)-DTPA onto the resin, Tl(III) is then eluted by a solution of HCl with SO2. The validity of this method was confirmed by assays of standard solutions of Tl(I) and Tl(III). The proposed method is shown to have an outstanding performance even in solutions with a high ratio of Tl(I)/Tl(III), and can be applied to aqueous samples with a high concentration of other electrolytes, which could interfere with the measurement. Portable equipment and reagents make it possible to use the proposed method routinely in the field.  相似文献   

17.
A method is presented for improved separation of 109Cd from silver cyclotron targets. After dissolution of the target material in nitric acid and removal of silver by precipitation with copper metal, at pH 5, the cadmium is separated from zinc, copper and other elements by anion exchange chromatography. The solution in 0.5 M nitric acid plus 0.1 M hydrobromic acid is percolated through a column containing 4 ml of AG1-X8 anion-exchange resin (100–200 mesh), equilibrated with the same acid mixture. Zinc, copper(II) and other elements are eluted with 50 ml of this mixture. Cadmium is retained and finally eluted with 50 ml of 3 M nitric acid. The cadmium is retained much more strongly from the hydrobromic acid mixture than from the 0.02 M hydrochloric acid used for such separations previously; the presence of the strongly absorbed nitrate anion in fairly high concentration completely eliminates the tailing of zinc observed in 0.02 M hydrochloric acid. A typical elution curve and results of quantitative separations are presented.  相似文献   

18.
《Analytical letters》2012,45(7):1193-1199
Abstract

A method to determine phytic acid within urine in the range 0.15–2 mg/l is reported. The method is based on the ICP atomic emission spectrometric determination of phosphorus, after previous separation and concentration of phytic acid using the anionic resin AG1-X8. The method has been applied successfully to determine phytic acid in synthetic urine and human urine.  相似文献   

19.
Abstract

The use of hydroxyl exchange resins (Dowex AG 1-X8 and AG 501-X8) as a component in the preparative clean up of biological samples for HPLC sugar and polyhydric alcohol analysis is inappropriate. On a weight specific basis, these resins bind 95–100% of monosaccharides (fructose and glucose), 45–85% of disaccharides (sucrose and trehalose) and 15–50% of polyhydric alcohols (glycerol and adonitol) present in sample solutions.  相似文献   

20.
This paper describes a new method for the production of 103Pd and 109Cd using the 66 MeV proton beam of iThemba LABS on a tandem natural silver target (Ag/Ag). The radiochemical separation of the Pd radionuclides (103Pd, 100Pd) from the bulk natAg was done using a Chelex-100 chelating resin column. The recovery of 103Pd from the irradiated natAg target was found to be >98 % without any Ag or Rh impurities detected. The radiochemical separation of 109Cd from the bulk natAg target was done by the precipitation of Ag ions by Cu followed by the separation of 109Cd, traces of Ag, Cu2+ and Rh using a AG1-X10 anion exchange resin column. The recovery yield of 109Cd was >99 % without any Ag or Rh impurities detected.  相似文献   

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