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A procedure was developed for determination of Np using HR Sequential ICP-AES. Mutual interference and background free spectral lines of Np at 295.66, 297.43, 297.49, 302.64 nm were identified. The samples of higher concentration (10–20 µg/mL) of Np had been analyzed. Analytical values of 10–20 µg/mL samples were found to be in good agreement with the expected amounts. The concentration of Np between 2 and 4 μg/mL slightly affected as compared to higher concentration. In U/Pu, Np-295.66, 297.43 nm lines were monitored which showed noticeable enhancement of their intensities. The repetitive analyses showed that the precision was better than 2% RSD.

ICP-AES based methodology was developed for the determination of trace metallic constituents in thorium matrix after preferential extraction of thorium using TBP, TOPO and DHOA. The distribution ratio for thorium followed the trend TOPO > TBP > DHOA with the formation of 1:2 complex. Oxalic acid was found to strip Th effectively. La, Ce, Pr, Gd, Dy, Lu can be determined at 0.1 mg L−1 using all the ligands, while common analytes can be determined at 0.1, 0.5 and 1 mg L−1 concentrations by using DHOA, TBP and TOPO, respectively.

Selective separation of uranium using bis(2,4,4-trimethylpentyl)phosphinic acid in xylene and C8mimNTf2 was investigated. For ionic liquid based system, the extraction kinetics was found to be slower with the predominance of ion exchange mechanism through [UO2(NO3)·2L]+, while for xylene based system solvation mechanism. The nature of the extracted species was found to be different in both the media as observed in luminescence study. Ionic liquid based system was more radioresistant than that of molecular diluents. Na2CO3 was successfully used for stripping. The selectivity was investigated by processing simulated high level waste of pressurized heavy water reactor origin.

Quality control analyses of Pu based nuclear fuels for trace metallic content by the DC-Arc-AES technique, produce a large amount of solid analytical waste containing Pu, U and Ag. Through the present study, an attempt was made to separate uranium from the bulk of the analytical waste using HNO3 leaching. Systematic studies have been carried out to optimize various parameters, such as acid molarity, contact time, and batch size, required to remove uranium preferentially from the solid waste leaving behind Pu and other impurities. The concentrations of U, Pu, Ag and other impurities during this exercise were intermittantly determined using ICP-AES.

An ICP-AES based methodology was developed for the determination of 22 trace metallic constituents (Ca, Co, Cr, Pb, Cu, Fe, Ga, In, Mg, Mn, Na, Ni, Sr, Zn, Eu, Sm, Gd, Dy, B, Be, Cd and Ag) in high purity neptunium matrix alongwith simultaneous determination of Np. Np 295.660 nm line was found to have the best analytical performance. The spectral interference of Np on other analytes have been investigated which includes identification of interference free line, evaluation of correction factor and tolerance level of neptunium. Presence of U, Th, Zr and Pu on the determination of Np has also been studied. The method was validated using synthetic samples.

An ICP-AES based method was developed for the direct determination of Phosphorous and Sulphur in U, Th and Zr matrices. Different analytical lines of P and S were identified and the calibration curves were established. Analytical performance of these analytical lines and the spectral interference of U, Th and Zr on these lines were studied systematically. The methodology for direct and trace level determination of P and S was found to be promissing, simple and less time consuming and it was validated using synthetic samples. The method was also found to be compared satisfactorily with the existing methods for their determination.

An attempt was made to prepare potassium plutonium sulphate, which is proposed to be the working reference material for analyzing plutonium based fuel samples and associated materials. X-ray diffraction was employed for phase characterization and the structure was found to be monoclinic in nature with a space group of P21/c. Trace metallic impurity analyses was carried out for the 26 elements e.g. Ag, Al, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Li, Mg, Mn, Mo, Na, Ni, Pb, Si, Sn, Sr, W, Zn, Dy, Eu, Sm and Gd using ICP-AES as well as D.C.Arc AES.

Sorption capacity of four plants (Funaria hygrometrica, Musa acuminata, Brassica juncea and Helianthus annuus) extracts/fractions for uranium, a radionuclide was investigated by EDXRF and tracer studies. The maximum sorption capacity, i.e., 100% (complete sorption) was observed in case of Musa acuminata extract and fractions. Carbohydrate, proteins, phenolics and flavonoids contents in the active fraction (having maximum sorption capacity) were also determined. Further purification of the most active fraction provided three pure molecules, mannitol, sorbitol and oxo-linked potassium oxalate. The characterization of isolated molecules was achieved by using FTIR, NMR, GC-MS, MS-MS, and by single crystal-XRD analysis. Of three molecules, oxo-linked potassium oxalate was observed to have 100% sorption activity. Possible binding mechanism of active molecule with the uranyl cation has been purposed.

A glove box adaptation of a high resolution atomic emission spectrometer (AES) is reported employing sequential radial viewing of an inductively coupled plasma (ICP) source for determination of trace metallic elements in plutonium bearing samples. The original compact ICP-AES unit was converted into separate units. All electronic and optical components were placed outside radioactive containment. The entire assembly of the ICP torch, radiofrequency coil, nebulizer, spray chamber, peristaltic pump, and drainage system were placed inside the glove box for the analysis of radioactive samples. All these modifications were achieved without any compromise on the analytical performance of the spectrometer. Operational experience of the instrument for analysis as well as additional information for the upkeep and maintenance of the same is described. Proper optical alignment of the ICP source and detection system was performed.

0.2 M CMPO in isodecanol(10%)–dodecane system was taken for evaluating the extraction behavior of actinides in different oxidation states. The order of decrease in distribution ratio at fixed acidity was found to be M 4 + > MO 2 2 + > M 3 + (M = actinide ion). The metal–ligand stoichiometry was determined by slope analysis. Though, increasing isodecanol content decreases the distribution ratio, no perturbation was found on O U O moiety as revealed by UV–vis spectroscopy. Application of van't Hoff equation to the extraction data at different temperatures enabled the determination of thermodynamic parameters. The radiolytic stability of the solvent system was evaluated by dose dependent study (gamma exposure in the range of 0–500 kGy). Finally the solvent system was used for actinide partitioning from simulated high level waste (SHLW) of fast breeder reactor (FBR) fuel.

Actinide partitioning studies with improved N,N,N',N'-tetraoctyl diglycolamide (TODGA) solvent (0.05 M TODGA + 5% iso-decanol in n-dodecane) has been explored in order to achieve better decontamination from fission products. The distribution behavior of various metal ions, viz. Am, Pu, U, Eu, Sr, Pd, Cs, Tc, Fe, and Mo with improved TODGA solvent was investigated. Lower concentration of TODGA (0.05 M as compared to previously proposed 0.1 M or 0.2 M) exhibited required extraction properties for actinide partitioning from pressurized heavy water reactor high level waste (PHWR-HLW). Counter-current extraction studies with simulated PHWR-HLW spiked with different radio-tracers (viz. 241Am, 152Eu, 137Cs, 85,89Sr, 59Fe, 106Ru, 109Pd, 95Zr, and 99Mo) suggested that > 99.9% of the trivalent actinides and lanthanides could be extracted in six stages and stripped in four stages. The decontamination factor for various fission products with respect to Am was: 3918 (Cs), 2990 (Sr), 1150 (Zr), 1407 (Ru), 1185 (Pd), an...

During the simultaneous extraction of plutonium and uranium using anion exchange chromatographic technique from analytical waste in hydrochloric acid medium, 241Am which is invariably present in the plutonium bearing fuel samples remains in the effluent. A two step separation scheme was developed for the recovery and purification of Am from the assorted waste to facilitate the disposal of large volume of aqueous waste and the purified Am solution was utilized for spectroscopic investigation. The separation scheme involved solvent extraction using 0.1 M TODGA + 0.5 M DHOA for separation of americium from Fe, Pb, Ni and Na followed by extraction chromatographic technique using CMPO on inert support as stationary phase for separation of Ca from Am. A systematic study on the extraction behavior of Am from hydrochloric acid medium revealed that out of four extraction systems well known for actinide partitioning namely 0.1 M TODGA + 0.5 M DHOA, 1 M DMDBTDMA, 0.2 M CMPO + 1.2 M TBP and 30% TRPO, only 0.1 M TODGA + 0.5 M DHOA extracts americium from 7.5 M HCl feed acidity. A comparative study involving CMPO solvent extraction and column chromatographic technique revealed that elution of Am from column is satisfactory as compared to inefficient stripping of Am from organic phase in solvent extraction technique using 0.1 M HNO3. The purity of the final solution was checked for 17 elements of interest and was found to be 98% pure, while the overall recovery of this two step separation scheme was found to be 95%.

‘Actinide partitioning’ studies were attempted by hollow fibre supported liquid membrane (HFSLM) technique using pressurized heavy water reactor simulated high level waste (PHWR-SHLW) as the feed. Two diglycolamide extractants for actinide partitioning, viz. 0.1 M TODGA (N,N,N´,N´-tetraoctyl diglycolamide) + 0.5 M DHOA (N,N-dihexyl octanamide) and 0.2 M T2EHDGA (N,N,N´,N´-tetra-2-ethylhexyl diglycolamide) + 30% iso-decanol in n-dodecane were used as the carrier solvent. Quantitative recovery of all trivalent actinides and lanthanides from PHWR-SHLW was achieved with both the carriers within 30 min when the feed volume was 0.5 L. On the other hand, about 18 h were necessary for a similar study carried out using a feed volume of 20 L. None of the other elements present in the PHWR-SHLW were transported, except small quantities of Sr and Mo. The product could be concentrated to two and four times by maintaining the feed to receiver phase volume ratio of 2:1 and 4:1, respectively. The transport behaviour of trivalent actinides and lanthanides by the two diglycolamide extractants were remarkably similar. The present studies revealed that diglycolamide-HFSLM system offers a promising alternative approach for ‘actinide partitioning’, where the use of organic solvent inventory could be drastically reduced. A mathematical model was developed and there was good agreement between the predicted and experimentally obtained data.

Trace metallic impurity analysis by spectroscopic techniques is one of the important steps of chemical quality control of nuclear fuel materials. Depending on the burn-up and the storage time of the fuel, there is an accumulation of 241Am in plutonium based fuel materials due to β decay of 241Pu. In this paper, attempts were made to develop a method for separation of 241Am from 1.2 kg of analytical solid waste containing 70% U, 23% Pu, 5% Ag and 1–2% C as major constituents along with other minor constituents generated during trace metal assay of plutonium based fuel samples by d. c. arc carrier distillation atomic emission spectrometry. A combination of ion exchange, solvent extraction and precipitation methods were carried out to separate ~45 mg of 241Am as Am(NO3)3 from 15 L of the analytical waste solution. Dowex 1×4 ion exchange chromatographic method was used for separation of Pu whereas 30% TBP–kerosene was utilized for separation of U. Am was separated from other impurities by fluoride precipitation followed by conversion to nitrate. The recovery of Pu from ion exchange chromatographic separation step was ~93% while the cumulative recovery of Am after separation process was found to be ~90%.

An analytical method was developed for the determination of indium and gallium in plutonium samples. A solvent extraction technique was employed by using 30% TBP in CCl4 for the quantitative separation of plutonium from the sample solution and subsequent determination by radial inductively coupled plasma atomic emission spectrometry (ICP-AES). The quantitative recovery of In and Ga in the separated samples was confirmed from radiometric/tracer studies. Recording of spectral profile at 303.396 nm for In and 403.298 nm for Ga has clearly indicated that the determination of Ga and In at lower concentrations will be affected by the presence of significant amounts of residual Pu in the aqueous phase due to spectral interference. These elements can be determined from ppm to % HNO3 and appropriate (100 mg and 1 g) sample size. The analytical range obtained for Ga and In was 0.1–1000 μg/mL and 0.05–500 μg/mL respectively by ICP-AES. Synthetic samples of plutonium containing indium and gallium in the range of 50–20000 ppm were analyzed.

Counter-current mixer-settler studies for actinide partitioning were carried using N,N,N′,N′-tetra-2-ethylhexyl diglycolamide (T2EHDGA) as the extractant. The feed solution was Simulated High Level Waste of Pressurized Heavy Water Reactor (PHWR-SHLW) origin spiked with 241Am, 244Cm, 152Eu, 137Cs, 85,89Sr, 59Fe, 106Ru, 109Pd, 95Zr, and 99Mo tracers. The organic stream was 0.1 M T2EHDGA + 5% isodecanol in n-dodecane. Extraction, scrubbing, and stripping experiments were performed by maintaining an organic to aqueous phase ratio of 1. More than 99.9% of the trivalent actinides and lanthanides were extracted in four stages, and the decontamination factors (D.F.) values were >103 obtained for most fission products. The co-extraction of Zr and Pd was prevented by the addition of oxalic acid and N-(2-hydroxyethyl)-ethylenediamine-triacetic acid (HEDTA) into the feed solution. However, ∼20% Ru and 10% Mo was extracted into the organic phase, which was successfully scrubbed using a mixture of 0.2 M oxalic...

Facilitated transport of actinides and lanthanides from nitrate medium has been investigated through a hollow fiber-supported liquid membrane using a mixture of N,N,N′,N′-tetraoctyl diglycolamide (TODGA) and N,N-di-n-hexyl octanamide (DHOA) in normal paraffin hydrocarbon (NPH) as the carrier solvent. The influence of aqueous feed composition on the permeability of Am(III) is reported. Quantitative transport of Am(III) was observed in 45 min from a feed solution containing 1 g/L Nd at 3.5 M HNO3. Similarly, quantitative transport of Am(III) was also achieved in 30 min from a simulated high-level waste (SHLW) solution containing ∼0.6 g/L total lanthanides. No significant transport of other metal ions present in SHLW was observed. Use of irradiated solvent suggested negligible change on the transport behaviour of Am(III). Hollow fiber-supported liquid membrane containing TODGA and DHOA in NPH appears promising for the separation of actinides from high-level waste.

Adsorption of thorium on the metal oxides impregnated silica has been investigated. The sorption kinetics revealed the trend in rate of Th sorption as iron oxide > chromium oxide > vanadium oxide. The sorption capacities were evaluated from Langmuir isotherm with the trend in the strength of the bonding chromium oxide > iron oxide > vanadium oxide. The sorption behavior was also analyzed comparing Dubinin–Radushkevich, Temkin and Freundlich isotherm. Oxalic acid was found to strip thorium effectively from sorbent. Chromium oxide–silica was found to be the most efficient and selective sorbent with co-sorption of Ag, Bi, Ga, In and Tl.

An ICP-AES based method was developed for the direct determination of precious metals without any chemical/physical separation in nuclear materials and it was found to be simple, sensitive, less time consuming, no organic waste generation and no need of selective extraction. Analytical performance including detection limits, sensitivity, linear dynamic range, precession of different analytical lines of these elements was studied alongwith the spectral interference of U, Th and Zr to choose the best analytical lines. EDXRF method was used for comparison purpose.

The electrothermal vaporization (ETV) mode of sample introduction into inductively coupled plasma (ICP) has been examined for its suitability for the analysis of trace metals in uranium and thorium compounds without prior chemical separation of the matrices using atomic emission spectrometry (AES). The ETV interfaced with an ICP torch adapted for glove box operation, has led to determination of sub-nanogram amounts of Al, Be, Ca, Cd, Co, Cr, Cu, Mg, Mn, Na, Ni, Zn, Dy, Eu, Gd and Sm using 10 μl of the sample aliquot containing 200 μg of U/Th matrix with a precision of 1–2%RSD. The results obtained here especially for rare earths in the presence of the matrix are of significance.

In order to examine the capability of energy dispersive X-ray fluorescence spectrometry for the determination of some common metallic impurities in nuclear grade U 3 O 8 matrix, a series of synthetic U 3 O 8 standards, containing impurities such as Ca, Co, Cr, Cu, Fe, Mn, Mo, Ni ,V, W and Zn in the concentration range, 100–1000 μg/g, were prepared. Using these standards, calibration curves were set up for different elements after optimizing the spectrometer parameters. Two synthetic samples and five reference standards obtained through an inter-laboratory comparison exercise within analytical laboratories of Department of Atomic Energy, India were analyzed to evaluate the performance of the newly developed analytical methods. The estimates for most of the analytes were in good agreement with the added amounts. The method is fast, since it requires no chemical treatment. The method has good precision for the analytes determined.

A solid sampling technique was developed for the ICP-AES determination of ultra-trace amounts of lanthanides chemically separated from U/Pu fuel materials. An essentially dc arc approach of using a buffer–carrier mixture of graphite–AgCl (4+1) was adopted to facilitate volatilization of the lanthanides. A 20 µl volume of lanthanide solution is loaded on 20 mg of carrier–buffer mixture placed in the crater of a Scribner–Mullin type of electrode system, evaporated under an IR lamp and introduced into the running argon plasma using a modified plasma torch assembly. The near total introduction of sample vapour into the plasma allows the determination of Dy and Eu at the 0.4 ng level and Gd and Sm can be determined at the 1 and 2 ng levels, respectively, with a precision of 10% RSD. The method is free from interferences due to the presence of concomitant lanthanides and common metals and has a significantly high tolerance to the presence of refractory U–Pu matrices.

Analytical atomic absorption/emission spectrometric methods have been developed for determination of 22 metallics at low concentration levels in high purity graphite material required in nuclear fuel industry. Of these, 21 metallics viz., Al,B, Be, Ca, Cd, Cr, Co, Cu, Fe, Li, Mn, Mo, Mg, Ni, Pb, Sn, Si, Ti, V, W and Zn are determined at trace concentration levels by D.C. arc Atomic Emission Spectrometric method using carrier excitation technique with a 6% carrier mixture of AgCl and NaF in a 5:1 proportion. Using the standardized procedure B, Be and Cd can be determined at 0.1 ppm concentrations while most of the other elements could be determined at 5–50 ppm concentrations. The detection limit for W was however 100 ppm. The precision of the method has been better than 20% RSD. The determination of silver is carried out by Electro-Thermal Atomization Atomic Absorption Spectrometric (ETA-AAS) technique by removal of graphite matrix by heating the sample in air at 850°C and dissolution of the resid...

A comprehensive trace metal assay of uranium silicide, a fuel for nuclear research reactors that employs low-enrichment uranium, is carried out by atomic spectrometry. Of the list of specification elements, 21 metallic elements are determined by a direct current (dc) arc carrier distillation technique; the rare earths yttrium and zirconium are chemically separated from the major matrix followed by a dc arc/inductively coupled argon plasma (ICP) excitation technique in atomic emission spectrometry (AES); silver is determined by electrothermal atomization-atomic absorption spectrometry (ETA-AAS) without prior chemical separation of the major matrix. Gamma radioactive tracers are used to check the recovery of rare earths during the chemical separation procedure. The detection limits for trace metallics vary in the 0.1- to 40-ppm range. The precision of the determinations as evaluated from the analysis of the synthetic sample with intermediate range analyte concentration is better than 25% relative standard deviation (RSD) for most of the elements employing dc arc-AES, while that for silver determination by ETS-AAS is 10% RSD. The precision of the determinations for four crucially important rare earths by ICP-AES is better than 3% RSD.

Trace amounts of plutonium in aqueous solutions have been determined by an inductively coupled argon plasma-atomic emission spectrometric (ICP-AES) technique. Extensive studies have been carried out on interelement interference effects for two plutonium lines, viz., 300.06 nm and 453.6 nm, due to the presence of uranium, thorium, lanthanides and other metallic elements in the sample solutions. The analytical range obtained in the present case is 0.1–100 μg/ml with a precision of better than 1% R.S.D. The method ie checked for accuracy by analyzing two wellcharacterizd reference rtandards.

Radio chemistry Division, Bhabha Atomic Research Centre. Trombay, Mumbai-400 085, India E-mail : svgod@barc.gov.in Manuscript received 7 August 2006, accepted 21 August 2006 A method has been developed for the determination of Sb in the presence of thorium matrix, using hydride generation technique in Flame Atomic Absorption Spectrometry with air-acetylene as oxidant fuel combination.Studies have been carried out in detail to obtain the maximum absorbance signal due to the formation of Sb hydride in presence of thorium matrix. The efficiency of which is normally governed by the factors such as oxidant-fuel flow rate,KI concentration, hydrochloric acid molarity and concentration of thorium matrix. This has led to the determination of antimony to a level as low as 0.4 pm on thorium basis using 5 mg/ml Th matrix.Analysis of synthetic samples revealed a good agreement between the estimates obtained with those of added amounts with a precision better than 5% RSD. It is of significance to note that the present method gains its uniqueness for its ability to determine the analyte without the need for a prior chemical separation of a matrix as complex as Th.

Radiochemistry Division, Bhabha Atomic Research Center, Trombay, Mumbai-400 085, India E-mail: agpage@magnum.barc.ernet.in Fax: 91-22-550515115519613 Manuscript received 5 September 2001, revised 4 October 2002, accepted 14 November 2002 An electrothermal atomization-atomic absorption spectrometric (ETA-AAS) method has been developed for the direct determination of Co, Cr and Mn in gallium matrix. The selective removal of volatile matrix has been achieved in the preatomization stage by controlling the furnace temperature at 1300° during the heating cycle. Nanogram amounts of analytes can be determined using 5 µl of 10 mg/ml gallium sample aliquot with a precision of 8% R.S.D.

An inductively coupled argon plasma-atomic emission spectrometric (ICP-AES) method has been developed for the direct determination of metallic constituents of high-critical temperature (Tc) superconducting materials with a precision of better than 2%. The typical sample matrices are YBa2Cu3O7−x, Bi2CaSr2Cu2O8 and TlBa2Ca2Cu3O8.5 and also with substitution at significant concentrations of elemental Fe, Gd, K, La, Mg, Na, Sn and Tm. The detection limits for these elements vary in the range 0.01–0.1 μg/ml. The method is based on dissolution of the solids and analysis of 1 mg/ml aliquot of the samples. Apart from optimisation of experimental parameters, the method also involves inter-element interference studies. It has been successfully applied for the chemical characterisation of a variety of oxide-based superconducting materials.

Uranium-aluminum alloys with a significant enrichment of uranium with /sup 233/U or /sup 235/U serve as nuclear fuels in research reactors. The quality assurance of this fuel requires, among other things, precise knowledge that all trace metal constituents that affect neutron economy, fuel integrity, and fuel fabrication process parameters are well within the specification limits. Trace metal characterization of /sup 235/U-Al alloy has been carried out by atomic spectrometry. The trace metal constituents of interest are grouped into common metals (silver, boron, calcium, cadmium, cobalt, chromium, copper, iron, magnesium, manganese, molybdenum, sodium, nickel, lead, silicon, tin, titanium, vanadium, tungsten, and zinc) and lanthanides (cerium, dysprosium, europium, gadolinium, holminium, lutetium, samarium, and terbium). The elements yttrium and zirconium are grouped with the latter in view of the chemical separation procedure used. The alloy samples are dissolved in 6 M HCl and evaporated to dryness with nitric acid, and the residue is ignited to oxide. The trace elements are determined by a dc arc emission spectrographic method after chemical separation. Of these, dysprosium, europium, gadolinium, and samarium are determined by inductively coupled plasma-atomic emission spectrometry also. These methods are found to be quite adequate for the requirements of U-Al alloy fuel samples.

An electrothermal atomization atomic absorption spectrometric (ET-AAS) method is developed for the direct determination of Ag,Be,Cd,Li and Pb in thorium nitrate solution. The method offers detection of sub-nanogram amounts of these analytes in 100 microgram thorium samples with a precision of around 10%. A number of spiked samples and pre-analysed Th02 samples have been analysed to evaluate the performance of the analytical methods developed here.

University Department of Chemistry, Bhavanagar University, Bhavavnagar Manuscript received 19 July 1980, revised 18 July 1981, accepted 11 August 1981 Some Ni(ll) Complexes of 4-Thiazolidinone Derivatives.