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1.
Separation of adsorbed radionuclides on diethylene glycol succinate (DGS) by diethylenetriaminepentaacetic acid (DTPA) was quantitatively performed. Adsorption between the radionuclides studied and DGS was attained at pH 5±0.5. Individual separations of60cobalt (II),90strontium (II),144cerium (III),233uranium (VI) and239plutonium (IV) were done by 25 ml of 10−4M of DTPA, as eluting agent, at different pH values.  相似文献   

2.
The formation property of Mo precipitate was investigated and improved the existing process was using H2O2 that acts as an interfering compound in a subsequent alumina adsorption process. The property of the Mo precipitate was investigated by using SEM, FTIR, TG-DTA, and XRD. The simulated solution consisted of 1M nitric acid containing seven elements (Mo, I, Ru, Zr, Ce, Nd, Sr) and their radioactive tracers. As a result, the precipitate was composed of the Mo precipitate and re-precipitated a-benzoinoxime which was added excessively for increasing the precipitation efficiency. It was confirmed that the Mo precipitate was formed by the reaction of two a-benzoinoxime molecules and one MoO2 2+. Molybdenum precipitate was dissolved in 0.4M NaOH solution within 5 minutes without H2O2. Hydrogen peroxide induced only the rapid dissolution of the a-benzoinoxime re-precipitate. Also, the dissolution method without H2O2 was favorable in the purification aspect because Zr and Ru were contained as a small fraction of 1.3% and 7.7%, respectively, in the dissolving solution.  相似文献   

3.
A method developed for the preparation of silver-coated alumina, a new material for retention of iodine from alkaline solution is described. Experiments were carried out, oriented to the purification step of 99Mo produced by uranium fission, based on the retention of radioiodine in this material. Iodine retention, as well as molybdenum non-retention, were found, both with excellent results. Further tests showed that the incorporation of this material has no influence on the subsequent 99Mo retention in ion exchange resins. The elution of the radioiodines retained was tested with satisfactory results. This new material can be used not only for improving the 99Mo purification and working conditions, but also as the basis of a method for recovering the fission produced 131I.  相似文献   

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5.
Factors affecting the Chromatographic separation of hydroxy acids by means of anion exchange resins in the borate form have been studied. With the acids studied the separation factor increases for a decreased borate concentration in the eluant. With complicated mixtures it is recommended to employ stepwise elution with solutions of increasing concentration.  相似文献   

6.
An ion exchange method has been worked out for the séparation of calcium and aluminum from iron. In the first step iron and aluminum are taken up in a column filled with an anion exchanger in the citrate form, whereas calcium passes into the effluent. Subsequently, aluminum is cluted by means of concentrated hydrochloric acid. The method has been adapted to the analysis of lime.  相似文献   

7.
The possibility has been investigated of separating rare-earth fission fragment elements from106Ru and137Cs by high-temperature sublimation (950°C) of chlorides, with their subsequent gas adsorption separation in a quartz tube under a temperature gradient in a flow of the carrier-gas Ar+SOCl2. The temperature corresponding to the maxima of the element precipitation zones are: 630–660°C (144Ce), 770–780°C (0.7–6 μg140La+La), 920°C (1.5 mg Ce or La), 420–450°C (106Ru), 280–300°C (137Cs). The coefficients of element separation have been calculated. For the separation of indicator amounts of rare-earth elements and106Ru and137Cs, fractional sublimation of the chlorides of the latter at 650°C has been used. Rate constants and effective activation energies of the overall processes of chlorination-sublimation of the elements have been determined.  相似文献   

8.
The effects of the Chernobyl disaster on lichens and pines, which are widely distributed in northern and western Turkey, have been examined within the four years between 1986–1990. Analyses of the plants studied by -spectrometry and spectrophotometric techniques have shown that the highest radioactive pollution was observed in the Pseudevernia furfuracea. The effects of Chernobyl on the ecosystem have been examined by comparing different plant species from the point of view of their reception and accumulation of fallout radionuclides.  相似文献   

9.
The detection limit of99Tc in (,) radio-activation analysis was determined in the presence of molybdenum and compared with that of99Tc in pure materials in the previous paper. The isotopic ratio of molybdenum in a99Mo–99mTc generator column could be simultaneously determined by photon activation analysis.  相似文献   

10.
A method of137Cs isolation from strongly, acidic solutions of fission products is described, in which vanadyl ferrocyanide is used as a selective ion exchanger for cesium. The effects of the acidity of medium and the carrier concentration on the quantitative yield of separation have been studied and convenient conditions have been found for137Cs isolation from the solution of fission products formed after irradiating uranium with neutrons.  相似文献   

11.
The possibilities of radioanalytical separation by isotopic exchange with metal chelate complexes and metal sulphide precipitates fixed in paper have been examined on the model system203Hg2++58Co2++65Zn2++24Na+.  相似文献   

12.
A study is presented on the use of isotopic and non-isotopic ion exchange in a heterogeneous liquid-liquid system for the separation of131I from water. The method is based on the reaction between radioiodide in the aqueous phase and trioctylmethylammonium iodide or chloride in the organic phase. The effect of some important experimental parameters on the separation efficiency is discussed. It has been found that under optimum conditions the method of isotopic ion exchange can be used for the radiochemical determination of iodine in water.  相似文献   

13.
This paper deals with a rapid method to determine radionuclides in reactor coolant by anion, cation, and anion-cation exchange membranes. A high pressure filtration device was established to simulate the THOR cooling water sampling system by means of several membranes mentioned above. The experimental results indicate that the adsorption efficiency of each membrane for several radionuclides is /1/ >95% with cation exchange membrane for Zn, Co, Na, Mn, Cu, Cs, Ba, La, W etc., /2/ >98% with anion exchange membrane for I, and /3/ <98% with anion-cation exchange membranes for Fe and Cr. The results are obtained using cooling water of Tsing Hua Open-Pool Reactor and the following radionuclides were identified:99mTc,140Ba,140La,51Cr,131I,58Co,60Co,54Mn,46Sc,59Fe,24Na, etc.  相似文献   

14.
The removal of phenol from aqueous solution was evaluated by using a nonfunctionalized hyper-cross-linked polymer Macronet MN200 and two ion exchange resins, Dowex XZ (strong anion exchange resin) and AuRIX 100 (weak anion exchange). Equilibrium experimental data were fitted to the Langmuir and Freundlich isotherms at different pHs. The Langmuir model describes successfully the phenol removal onto the three resins. The extent of the phenol adsorption was affected by the pH of the solution; thus, the nonfunctionalized resin reported the maximum loading adsorption under acidic conditions, where the molecular phenol form predominates. In contrast both ion exchange resins reported the maximum removal under alkaline conditions where the phenolate may be removed by a combined effect of both adsorption and ion exchange mechanisms. A theoretical model proposed in the literature was used to fit the experimental data and a double contribution was observed from the parameters obtained by the model. Kinetic experiments under different initial phenol concentrations and under the best pH conditions observed in the equilibrium experiments were performed. Two different models were used to define the controlling mechanism of the overall adsorption process: the homogeneous particle diffusion model and the shell progressive model fit the kinetic experimental data and determined the resin phase mechanism as the rate-limiting diffusion for the phenol removal. Resins charged after the kinetic experiments were further eluted by different methods. Desorption of nonfunctionalized resin was achieved by using the solution (50% v/v) of methanol/water with a recovery close to 90%. In the case of the ion exchange resins the desorption process was performed at different pHs and considering the effect of the competitive ion Cl. The desorption processes were controlled by the ion exchange mechanism for Dowex XZ and AuRIX 100 resins; thus, no significant effect for the addition of Cl under acidic conditions was observed, while under alkaline conditions the total recovery increased, specially for Dowex XZ resin.  相似文献   

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16.
Uranium determination in environmental samples is faced with problems due to presence of iron and other major elements. Iron is also used many a times for pre-concentration of uranium and actinides. Separation of milligram quantity of Fe from microgram quantity of uranium becomes essential during the estimation step. A simple two step procedure has been standardized for separating uranium and iron using anion exchange in 0.025 M H2SO4. Quantitative recovery of uranium was obtained as well as good separation from iron. This method was applied for estimation of uranium in water samples.  相似文献   

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18.
A method for the determination of aluminium(III) ions based on separation by cation exchange column chromatography and detection by conductivity detector has been developed. It is fast and reliable, and can be used for the separation and analysis of aluminium(III) ions from other metal ions like Mg(II), Mn(II), Zn(II), Co(II), Ca(II), Sr(II), rare earth elements like Lu(III), Tm(III), and Gd(III), which are eluted at different times and so do not interfere. Effect of p-phenylene diamine concentration present in the eluent, presence of other metal ions and effect of various anions present in the injection sample on the separation and analysis of aluminium(III) ions have also been studied.  相似文献   

19.
Arsenite, arsenate, monomethylarsonate, dimethylarsinate, arsenobetaine, arsenocholine and the tetramethylarsonium ion were subjected to ion-exchange and ion-pair reversed phase HPLC. The ion exchange method was superior in selectivity and time of analysis for the arsenic anions. The ammonium ions used for the ion-pair method only resulted in separation of some of the anionic arsenic compounds. Flame atomic absorption spectrometry was used for on-line arsenic-specific detection.  相似文献   

20.
Journal of Radioanalytical and Nuclear Chemistry - Analysis of irradiated material shortly after irradiation can be non-trivial due to highly radioactive activation and fission isotopes increasing...  相似文献   

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