Characterization of waste and soil - Determination of elemental composition by X-ray fluorescence

This European Standard specifies the procedure for a quantitative determination of major and trace element concentrations in homogeneous solid waste, soil and soil-like material by energy dispersive X-ray fluorescence (EDXRF) spectrometry or wavelength dispersive X-ray fluorescence (WDXRF) spectrometry using a calibration with matrix-matched standards.
This European Standard is applicable for the following elements: Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Y, Zr, Nb, Mo, Ag, Cd, Sn, Sb, Te, I, Cs, Ba, Ta, W, Hg, Tl, Pb, Bi, Th and U. Concentration levels between approximately 0,000 1 % and 100 % can be determined depending on the element and the instrument used.

Charakterisierung von Abfällen und Böden - Bestimmung der elementaren Zusammensetzung durch Röntgenfluoreszenz-Analyse

Caractérisation des déchets et du sol - Détermination de la composition élémentaire par fluorescence X

La présente norme décrit le mode opératoire de détermination quantitative des concentrations en éléments
majeurs et en éléments traces dans les sols, les matériaux de type sol et les déchets solides homogenes a
l?aide de spectrometres de fluorescence X a dispersion d?énergie (EDXRF) ou de spectrometres de
fluorescence X a dispersion de longueur d?onde (WDXRF), en utilisant un étalonnage réalisé avec des
références internes a l?appareil.
Cette norme est applicable aux éléments suivants : Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni,
Cu, Zn, As, Se, Br, Rb, Sr, Y, Zr, Nb, Mo, Ag, Cd, Sn, Sb, Te, I, Cs, Ba, Ta, W, Hg, Tl ,Pb, Bi, Th et U. Il est
possible de déterminer des niveaux de concentration compris entre 0,001 % et 100 % selon l?élément dosé et
l?instrument utilisé.

Karakterizacija odpadkov in zemljine - Določevanje elementne sestave z rentgensko fluorescenco

General Information

Status
Published
Publication Date
11-Sep-2007
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
11-Sep-2007
Due Date
16-Nov-2007
Completion Date
12-Sep-2007

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2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Characterization of waste and soil - Determination of elemental composition by X-ray fluorescenceCaractérisation des déchets et du sol - Détermination de la composition élémentaire par fluorescence XCharakterisierung von Abfällen und Böden - Bestimmung der elementaren Zusammensetzung durch Röntgenfluoreszenz-AnalyseTa slovenski standard je istoveten z:EN 15309:2007SIST EN 15309:2007en13.080.10Chemical characteristics of soils13.030.10Trdni odpadkiSolid wastesICS:SLOVENSKI
STANDARDSIST EN 15309:200701-oktober-2007







EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 15309May 2007ICS 13.030.10; 13.080.10 English VersionCharacterization of waste and soil - Determination of elementalcomposition by X-ray fluorescenceCaractérisation des déchets et du sol - Détermination de lacomposition élémentaire par fluorescence XCharakterisierung von Abfällen und Böden - Bestimmungder elementaren Zusammensetzung durchRöntgenfluoreszenz-AnalyseThis European Standard was approved by CEN on 22 March 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2007 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 15309:2007: E



EN 15309:2007 (E) 2 Contents Page Foreword.3 Introduction.4 1 Scope.5 2 Normative references.5 3 Terms and definitions.5 4 Safety remarks.7 5 Principle.7 6 Apparatus.7 7 Reagents.8 8 Interferences and sources of error.8 9 Sample preparation.9 9.1 General.9 9.2 Drying and determination of dry mass.9 9.3 Preparation of pressed pellet.9 9.4 Preparation of fused beads.10 10 Procedure.10 10.1 Analytical measurement conditions.10 10.2 Calibration.11 10.3 Analysis of the samples.17 11 Quality control.18 11.1 Drift correction procedure.18 11.2 Blank test.18 11.3 Reference materials.18 12 Calculation of the result.18 13 Test report.19 Annex A (informative)
Semi-quantitative screening analysis of waste, sludge and soil samples.20 Annex B (informative)
Examples for operational steps of the sample preparation for soil and waste samples.23 Annex C (informative)
Suggested analytical lines, crystals and operating conditions.29 Annex D (informative)
List of reference materials applicable for XRF-analysis.31 Annex E (informative)
Validation.32 Bibliography.40



EN 15309:2007 (E) 3 Foreword This document (EN 15309:2007) has been prepared by Technical Committee CEN/TC 292 “Characterization of waste“, the secretariat of which is held by NEN. This document has been prepared in coordination with ISO/TC 190 “Soil quality”. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by November 2007, and conflicting national standards shall be withdrawn at the latest by November 2007. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom



EN 15309:2007 (E) 4 Introduction X-ray fluorescence spectrometry is a fast and reliable method for the quantitative analysis of the total content of certain elements within different matrices. The quality of the results obtained depends very closely on the type of instrument used, e.g. bench top or high performance, energy dispersive or wavelength dispersive instruments. When selecting a specific instrument several factors have to be considered, such as the matrices to be analyzed, elements to be determined, detection limits required and the measuring time. The quality of the results depends on the element to be determined and on the surrounding matrix. Due to the wide range of matrix compositions and the lack of suitable reference materials in the case of inhomogeneous matrices like waste, it is generally difficult to set up a calibration with matrix-matched reference materials. Therefore this standard describes two different procedures:  a quantitative analytical procedure for homogeneous solid waste, soil and soil-like material in the normative part. The calibration is based on matrix-matched standards;  an XRF screening method for solid and liquid material as waste, sludge and soil in the informative
Annex A which provides a total element characterisation at a semi-quantitative level. The calibration is based on matrix-independent calibration curves, previously set up by the manufacturer.



EN 15309:2007 (E) 5 1 Scope This European Standard specifies the procedure for a quantitative determination of major and trace element concentrations in homogeneous solid waste, soil and soil-like material by energy dispersive X-ray fluorescence (EDXRF) spectrometry or wavelength dispersive X-ray fluorescence (WDXRF) spectrometry using a calibration with matrix-matched standards. This European Standard is applicable for the following elements: Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Y, Zr, Nb, Mo, Ag, Cd, Sn, Sb, Te, I, Cs, Ba, Ta, W, Hg, Tl, Pb, Bi, Th and U. Concentration levels between approximately 0,000 1 % and 100 % can be determined depending on the element and the instrument used. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 14346, Characterisation of waste — Calculation of dry matter by determination of dry residue or water content EN 15002, Characterisation of waste — Preparation of test portions from the laboratory sample EN ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories (ISO/IEC 17025:1999) ISO 11464, Soil quality — Pretreatment of samples for physico-chemical analysis ISO 11465, Soil quality — Determination of dry matter and water content on a mass basis — Gravimetric method 3 Terms and definitions For the purpose of this document, the following terms and definitions apply. NOTE See [13] and [10] for non specified terms. 3.1 absorption edge jump of the mass absorption coefficient at a specific wavelength or energy 3.2 absorption of X-rays loss of intensity of X-rays by an isotropic and homogenous material as described by the Bouger-Lambert law 3.3 analytical line specific characteristic X-ray spectral line of the atom or ion of the analyte used for determination of the analyte content 3.4 Bremsstrahlung; continuous radiation electromagnetic radiation produced by the acceleration of a charged particle, such as an electron, when deflected by another charged particle, such as an atomic nucleus



EN 15309:2007 (E) 6 3.5 Compton-line spectral line due to incoherent scattering (Compton-effect) occurring when the incident X-ray photon strike an atom without promoting fluorescence NOTE Energy is lost in the collision and therefore the resulting scattered X-ray photon is of lower energy than the incident X-ray photon. 3.6 drift correction monitors physically stable samples used to correct for instrumental drift 3.7 emitted sample X-rays radiation emitted by sample consisting of X-ray fluorescence radiation and scattered primary X-rays 3.8 fused bead analyte sample prepared by dissolution in a flux 3.9 liquid sample analyte sample submitted as a solution for direct measurement in the sample cup 3.10 mass absorption coefficient constant describing the fractional decrease in the intensity of a beam of
X-radiation as it passes through an absorbing medium, expressed in units of cm2/g. The mass absorption coefficient is a function of the wavelength of the absorbed radiation and the atomic number of the absorbing element 3.11 polarised excitation X-ray spectrometer energy dispersive X-ray spectrometer where the excitation is performed by polarised radiation and the emitted X-ray fluorescence radiation is detected along the direction of polarisation 3.12 powder sample analyte sample submitted as a powder for direct measurement in the sample cup 3.13 precision closeness of agreement of results obtained by applying the method several times under prescribed conditions [ISO 5725-2:1994] 3.14 pressed pellet analyte sample prepared by pressing milled material into a disk 3.15 primary X-rays X-rays by which the sample is radiated 3.16 quality control sample stable sample with known contents, e.g. certified reference material (CRM) used to monitor instrument and calibration performance



EN 15309:2007 (E) 7 3.17 X-ray fluorescence radiation emission of characteristic X-rays from a sample that has been bombarded by high-energy X-rays or gamma rays 4 Safety remarks Anyone dealing with waste and sludge analysis has to be aware of the typical risks that this kind of material presents irrespective of the parameter to be determined. Waste and sludge samples may contain hazardous e.g. toxic, reactive, flammable, infectious substances, which could potentially undergo biological and/or chemical reaction. Consequently it is recommended that these samples should be handled with special care. The gases that may be produced by microbiological or chemical activity are potentially flammable and will pressurise sealed bottles. Bursting bottles are likely to result in hazardous shrapnel, dust and/or aerosol. National regulations should be followed with respect to all hazards associated with this method. The X-ray fluorescence spectrometer shall comply with European and national regulations relevant to radiation protection. The person responsible for managing or supervising the operation of X-ray equipment shall provide evidence of his knowledge of radiation protection according to national regulations. 5 Principle After a suitable preparation, if necessary, the sample is introduced into a XRF-spectrometer and excited by primary X-rays. The intensities of the secondary fluorescent energy lines specific for each element are measured and the elemental composition of the sample is determined by reference to previously established calibration graphs or equations and applying corrections for inter-element effects. The calibration equations and inter-element corrections are established using pure reagents and/or series of internal or reference materials providing they meet all the requirements of the relevant preparation technique.
6 Apparatus 6.1 X-ray fluorescence spectrometer The X-ray fluorescence spectrometer shall be able to analyse the elements according to the scope of this European Standard. The following types of X-ray fluorescence spectrometers are applicable:  energy dispersive X-ray fluorescence (EDXRF) spectrometer that achieves the dispersion of the emitted X-ray fluorescence radiation by an energy dispersive detector;  wavelength dispersive X-ray fluorescence (WDXRF) spectrometer that achieves the dispersion of the emitted X-ray fluorescence radiation by diffraction by a crystal or a synthetic multilayer. The spectrometer consists of a number of components:  primary X-ray source, an X-ray tube with a high voltage generator;  a sample holder;  detector unit including electronic equipment;  source modifiers to modify the shape or intensity of the source spectrum or the beam shape (like source filters, secondary targets, polarising targets, collimators, focussing optics etc.).



EN 15309:2007 (E) 8 The detector unit is different for WDXRF and for EDXRF spectrometers. WDXRF spectrometers take advantage of the dispersion of the emitted radiation by scattering by a crystal or a synthetic multilayer. The detector does not need to be capable of energy discrimination. EDXRF spectrometers use an energy dispersive detector. Pulses of current from the detector, which are a measure of the energy of the incoming X-rays, are segregated into channels according to energy using a Multi-Channel Analyser (MCA). NOTE 1 The use of a high-energy X-ray tube increases the potential for losses of volatile analytes from samples by heating in the spectrometer during analysis. NOTE 2 The new generation of EDXRF spectrometers takes advantage of the polarising target theory resulting in a significant decrease of the background scattering, and therefore lower limits of detection can be achieved (comparable to WDXRF). 6.2 Mill, preferable with walls made of agate, corundum or zircon. 6.3 Pellet preparation equipment: manual or automatic pellet press, capable of providing a pressure of at least 100 kN. 6.4 Aluminium cup: supporting backing cup for pressed pellets. 6.5 Fusion apparatus: electric, gas or high frequency induction furnace that can be heated up to a fixed temperature of between 1 050 °C and 1 250 °C. 6.6 Fusion crucibles: crucibles made of non-wetting platinum alloy (Pt 95 %; Au 5 % is suitable). Lids, if used, shall be made from platinum alloy. NOTE Certain metal sulphides (so called platinum poisons) affect the platinum crucibles in which the sample is melted. 6.7 Casting moulds: non-wetting platinum alloy (Pt 95 %; Au 5 % is suitable). 7 Reagents The reagents mentioned are used as carrier material. 7.1 Binder: liquid or solid binder free of analytes of interest. Solid materials can contain a certain amount of moisture, which shall be compensated for. NOTE Different type of binders may be used. A binder commonly used is wax. 7.2 Flux: solid flux free of analytes of interest. Solid materials can contain a certain amount of moisture, which shall be compensated for (see EN ISO 12677 for compensation for moisture in flux). NOTE Different type of fluxes may be used. Fluxes commonly used are lithium metaborate, lithium tetraborate or mixtures of both. 8 Interferences and sources of error The container in which the sample is delivered and stored can be a source of error. Its material shall be chosen according to the elements to be determined. NOTE Elemental Hg can penetrate polyethylene walls very rapidly in both directions. In the case of glass containers, contamination may be observed for some elements e.g. Al, As, Ba, Ce, K, Na, Pb. Interferences in X-ray fluorescence spectrometry are due to spectral line overlaps, matrix effects, spectral artefacts and particle size or mineralogical effects.



EN 15309:2007 (E) 9 Spectral line overlaps occur when an analytical line cannot be resolved from the line of a different element. Corrections for these interferences are made using the algorithms provided with the software. Matrix effects occur when the X-ray fluorescence radiation from the analyte element is absorbed or enhanced by other elements in the sample before it reaches the detector. In the case of complex matrices these effects generally have to be corrected. Spectral artefacts e.g. escape peaks, sum peaks, pulse pile up lines, dead time, Bremsstrahlung correction, are accounted for by the provided software. Spectral artefacts differ for energy dispersive and wavelength dispersive XRF spectrometry. Particle size effects can be reduced by milling the sample, and both particle size and mineralogical effects can be eliminated by preparing bead samples. It is vital for quantitative analysis that the same sample preparation procedure is applied to both the standards and the samples to be analysed. 9 Sample preparation 9.1 General In analysis by XRF spectrometry the sample preparation step is crucial as the quality of the sample preparation will strongly influence the accuracy of the results. For quantitative analysis of solid samples, pressed pellets or fused beads have to be prepared. The application of the pressed pellet method is recommended for the quantification of trace elements and mandatory for the quantification of volatile elements, and the fused bead method for the determination of non-volatile major and minor elements. NOTE 1 The preparation of fused beads eliminates effects due to particle size and mineralogy. The conditions of the preparation of fused beads shall be adapted to the matrix properties. Otherwise the preparation of fused beads may be difficult or cause problems in case of waste like matrices as sludges. For a given calibration the same preparation method shall be used throughout, for both samples and standards. NOTE 2 Depending on the sample type other sample preparation methods may be applied according to Annex B. For precise quantitative measurements, homogeneous and representative test portions are necessary. Pre-treatment and preparation of test portions shall be carried out according to the appropriate clauses of ISO 11464 and EN 15002. The particle size of the sample may strongly affect the precision of the measurement. The particle size should preferably be smaller than 150 µm. NOTE 3 Particle size smaller than 80 µm is recommended for the analysis of low atomic mass elements when using the pressed pellet method. 9.2 Drying and determination of dry mass Prepare and dry the sample according to ISO 11464 or EN 15002. Determine the dry mass according to ISO 11465 or EN 14346. 9.3 Preparation of pressed pellet After drying and milling or grinding the sample, a pellet is prepared in the pellet press (6.3). Before pressing, the sample shall be mixed and homogenised with a binder (7.1). For the preparation of 40 mm diameter pellets, about 10,0 g of sample is taken, for 32 mm diameter pellets about 4,5 g of sample is required. The amount of binder in the pellet shall be taken into account for the dilution factor. It is recommended to press the sample in an aluminium cup (6.4) as support.



EN 15309:2007 (E) 10 NOTE 1 Different type of binders can be used. A binder commonly used is wax. In the case of a liquid binder the pellet is placed in an oven to evaporate organic solvent. NOTE 2 Different dilution factors can be used. A proportion of sample: binder commonly used is 10:1 by weight.
9.4 Preparation of fused beads After drying and milling or grinding the sample, a fused bead is prepared using the fusion apparatus (6.5). Ignite the sample at an appropriate temperature until constant mass is reached. Determine the loss on ignition at the same temperature to correct for volatile elements and/or compounds being released during ignition of the sample. NOTE 1 The ignition temperature can vary depending on the sample matrix. A temperature commonly used is 1025°C ± 25°C.
Because of the wide applicability of the fused bead technique, various fluxes and modes of calibration are permitted providing they have been demonstrated to be able to meet certain criteria of reproducibility, sensitivity and accuracy. For application of alkaline fusion technique (e.g. selection of flux, fusion temperature, additives) ISO 14869-2 or CEN/TR 15018 should be used. NOTE 2 Fluxes commonly used are lithium metaborate, lithium tetraborate or mixtures of both. NOTE 3 Loss of volatile elements e.g. As, Br, Cd, Cl, Hg, I, S , Sb, Se, Tl may occur during the ignition and fusion processes. Also Cu may be volatile if a bromide releasing agent is used. The flux (7.2) is added to the ignited material. For the preparation of 40 mm diameter beads, about 1,6 g of ignited sample is taken, for 32 mm diameter beads about 0,8 g of ignited sample is required. The amount of flux in the bead shall be taken into account for the dilution factor. The same sample preparation procedure and ratio of sample to flux shall be used for samples and standards. The beads produced should be visually homogeneous and transparent. NOTE 4 Non ignited material may be used to prepare beads but, nevertheless, loss of ignition needs to be determined and needs to be taken into account in the calculation of the results. It should be noted that non ignited material may contain compounds that can damage the platinum crucibles during fusion. NOTE 5 Different dilution factors may be used. A proportion of sample: flux commonly used is 1:5 by weight. After fusion in a platinum-gold crucible (6.6) the melt is poured into a casting mould (6.7) to make a bead. NOTE 6 Beads can deteriorate because of adverse temperature and humidity conditions, so it is recommended that beads are stored in desiccators. 10 Procedure 10.1 Analytical measurement conditions 10.1.1 Wavelength dispersive instruments The analytical lines to be used and suggested operating conditions are given in Table C.1. The settings are strongly dependant on the spectrometer configuration, e.g. the type of X-ray tube (Rh, Cr), tube power, available crystals, type of collimators.



EN 15309:2007 (E) 11 Intensities and background corrections For the determination of trace elements the measured intensities have to be background corrected. The measured background positions should be free of spectral line interferences. The net peak intensity I, expressed as the number of counts per second of the element of interest, is calculated as the difference between the measured peak intensity of the element and the background intensity:
bpIII−= (1) where
pI is the count rate of the element i, expressed as the number of counts per second;
bI is the background count rate of the element i, expressed as the number of counts per second. Counting time The minimum counting time is the time necessary to achieve an uncertainty (%2σ), which is less than the desired precision of the measurement. Choose a reference material with a concentration level in the middle of the working range and measure the count rate. The counting time for each element can be calculated according to:
2bp%1.2100−=IItσ (2) where
t is the total counting time for the peaks and background in seconds;
%2σ is the relative target precision at a confidence level of 95 %, expressed as percentage. 10.1.2 Energy dispersive instruments The analytical lines to be used and suggested operating conditions are given in Table C.2. The settings are strongly dependant on the spectrometer configuration, e.g. type of X-ray tube (Rh, Pd), tube power, available targets, type of filters. Intensities and background corrections Deconvolution of the spectra and background correction are needed when analysing samples with overlapping lines. Usually XRF-instruments are supplied with a specific software module for that purpose. 10.2 Calibration 10.2.1 General The calibration procedure is similar for energy dispersive and wavelength dispersive techniques. In general calibration is established by using matrix-adapted reference materials. The calibration equations and inter-element corrections are calculated by the software of the instrument. An accuracy check is performed with CRMs or samples with known composition.



EN 15309:2007 (E) 12
Different procedures for correcting matrix effects may be used according to the analytical accuracy required:  the scattered radiation method is based on the principle that the intensities of the analyte line and of the Compton line are affected in the same proportion due to the overall mass absorption coefficient of the sample. This linear relationship holds when all analytes are at low concentrations (trace elements) and their absorption coefficients are not affected by an adjacent absorption edge. In this case an internal Compton correction can be used. Beside that, a correction method using the Compton intensity with Mass Absorption Coefficients (MAC) is also applicable. In this method, the intensities of the major elements are measured to apply a jump edge correction for the analysed trace elements;  correction using the fundamental parameter approach;  correction using theoretical correction coefficients (alphas) taking basic physical principles, instrumental geometry etc. into account;  correction using empirical correction coefficients (alphas) based on regression analysis of standards with known elemental concentrations. 10.2.2 General calibration procedure For calibration purposes the measurement of analyte lines of samples of known composition is needed. The basic equation implies a linear relationship between the intensity and the concentration.
ii,1i,0i.IaaC+= (3) where
iC is the concentration of the element of interest, expressed as mg/kg or percentage dry matter;
i,0a is the offset of the calibration curve;
i,1a is the slope of the calibration curve;
iI is the net intensity of the element of interest, expressed as counts per second. Matrix effects have to be taken into account in X-ray spectrometry according to the following equation:
MIaaC.).(ii,1i,0i+= (4) where
M is the correction term due to the matrix effects.
The matrix effect correction term may consist of an internal standard Compton correction method or may be calculated from mathematical models. 10.2.3 Internal standard correction using Compton (incoherent) scattering method The measured intensity of incoherent scattering may be used directly to compensate for matrix effects or indirectly for the determination of the effective mass absorption coefficient µ to correct for matrix effects. The compensation for matrix effects is based on a
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