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Workshop for XRF-Spectrometry Anne Wegner, 2014 Dec 4th, Athens
X-ray fluorescence analysis (XRF) or X-ray spectrometry
• A method to do qualitative and quantitative analysis of the elemental composition by excitation of atoms and detection of their characteristic X-rays
X-ray fluorescence Spectrometry (XRF) Definition
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X-ray fluorescence Spectrometry (XRF) Advantages
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• Solid and liquid samples can be analysed directly
• Little or no sample preparation required
• non-destructive
• Sampling-analysis result time relatively short
• Elemental range: (Be) Na to U
• Linearity from ppm to 100%
• long term stability
• Quantitative, qualitative and semi-quantitative
X-ray fluorescence Spectrometry (XRF) Applications
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Cement Minerals &
Mining Petrochemistry
Ceramics Geology Metals Chemistry
Research
Samples measured as
• Liquids
• directly
• Powders
• directly
• as pressed pellets
• as fused beads
• Bulks
• directly, after fitting into sample cups
X-ray fluorescence Spectrometry (XRF) Capabilities
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• Qualitative Analysis
• Identification of elements
• „What’s inside?”
• Quantitative Analysis
• Determination of concentrations
• „How much is inside?”
• Semi-Quantitative Analysis
• Estimation of concentration
• „About how much?”
X-ray fluorescence Spectrometry (XRF) Capabilities
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X-ray fluorescence Spectrometry (XRF) Principle
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• Sample is excited by X-Rays
• Emission of X-ray Fluorescence from Elements inside the sample
• Energies of X-Ray Fluorescence charcteriastic for elements
• Energies = qualitative (Which Element?)
• Intensities = quantitative (How much of a certain element?)
XRF analysis covers the following energy- respective wavelength range:
• E = 0.1 – 60.0 keV
• l = 11.30 – 0.02 nm
• Elemental range from Berylium (Be) to Uranium (U)
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X-ray fluorescence Spectrometry (XRF) What are X-Rays?
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X-ray fluorescence Spectrometry (XRF) What are X-Rays?
• X-rays are electromagnetic radiation having a dual character
• They have the properties of waves, i.e. they will show the typical characteristics like diffraction
• They have the properties of particles, i.e. they e.g. be able to collide with other particles and thus interact with them
• Subsequently, they are particles moving through space like a wave
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X-ray fluorescence Spectrometry (XRF) Creation of X-Ray Fluorescence inside the sample
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X-Ray Fluorescence
Fe
Cr
Ni
Fe
Cr
Ni
Fe
Cr
Ni
Fe
Cr
Ni Sample
X-ray fluorescence Spectrometry (XRF) Creation of X-Ray Fluorescence inside the sample
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K radiation
X-ray fluorescence Spectrometry (XRF) Creation of X-Ray Fluorescence inside the sample
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L radiation
Example Spectra of a Coin
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• Spectra of 1 € Coin
X-ray fluorescence Spectrometry (XRF) Creation of X-Ray Fluorescence inside the sample
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Coherent Scatter
Incoherent Scatter Incident Beam
Diffraction
Absorption X-Ray Fluorescence
Fe
Cr
Ni
Fe
Cr
Ni
Fe
Cr
Ni
Fe
Cr
Ni Sample
X-ray fluorescence Spectrometry (XRF) Fluorescence Yield
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• The actual number of X-ray photons produced from an atom is less than expected
• The ratio of the useful X-ray photons to the total number of primary photons is called the Fluorescent Yield (ω)
• Lower Intensities for lighter elements
wk(B) 10-4
wk(Fe) 0.35
wk(Te) 0.88
Different Setups for X-Ray Fluorescence
Different Setups for X-Ray Fluorescence WD-XRF vs ED-XRF
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• Wavelength-Dispersive XRF • Energy-Dispersive XRF
Workshop XRF Athens – Anne Wegner
• X-rays produced by a tube are directed to the sample • Causes sample to
produce X-rays that are characteristic of the atoms (elements) present
• Analyzer crystals are used
to separate the X-rays into their individual components
• Detectors are used to convert the X-ray energy into an electrical pulse that is counted
X-ray fluorescence analysis (XRF) WDXRF – sequential
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X-ray fluorescence analysis (XRF) WDXRF – sequential
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The Comparison of Wavelength and Energy Dispersive Spectrometers WD-XRF
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n = 1, 2, 3,… (reflection order)
d = interplanar lattice spacing (nm)
θ = diffraction angle (°)
E = Energy of Photon (keV)
POLYCHROMATIC MONOCHROMATIC
nλ = 2d∙ sinθ
𝐴𝐵𝐶=2d∙ sinθ ′AC′
d= sin θ
′𝐴𝐶′ = d sin θ
′𝐴𝐶𝐵′ = 2d sin θ
′𝐴𝐶𝐵′ = nλ
λ = 1,24
𝐸
Three Analyzer Crystals • LiF 200 and PET are natural crystals
• XS-55 is a synthetic multilayer (sputtered)
X-ray fluorescence analysis (XRF) Basic Configuration
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The Comparison of Wavelength and Energy Dispersive Spectrometers WD-XRF
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Sample
Proportional detector
Crystal
Scintillation detector
• An analyzer crystal is used to
seperate the various
wavelangth λ (energies)
• The detector records the
number N of X-ray photons at
a given wavelength (energy)
• Two detectors are used to
cover the whole elemental
range
Propotional detector B to Cr
Scintillation detector Mn to U
• Same as for sequential WDXRF
• For each element there is one channel including analyzer crystal and detector
• No goniometer
• No scanning possible
Very Fast but less flexibile
X-ray fluorescence analysis (XRF) WDXRF – simultaneous
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• Cheaper
• Smaller
• Mechanical simplicity
• Detector is used to detect both
• Energy of the incoming X-rays
• Intensity of the incoming X-rays
X-ray fluorescence analysis (XRF) EDXRF
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Instrumentation for X-ray Spectrometry The Comparison of Wavelength and Energy Dispersive Spectrometers
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Sample
• The detector is used to
record both
• the energy E
• the number N of X-ray
photons at a given energy.
• No Soller slits (collimators as
used in WD-XRF) and no
crystals are required.
X-ray fluorescence analysis (XRF) AXS Product Line
Wavelength-Dispersive
(WDXRF)
Simultaneous Sequential
Energy-Dispersive (EDXRF)
S8 LION S8 DRAGON
S8 TIGER S2 RANGER
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• Large difference in resolution between WDXRF and EDXRF
• In WDXRF the combination crystal, collimator, detector gives us a much higher resolution
• In EDXRF the resolution only depends on the detector
X-ray fluorescence analysis (XRF) EDXRF vs. WDXRF – The Difference
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• Steel sample with 0,31% Co
Co Ka1 line is overlapped by
Fe Kb1
Metal applications WDX
X-ray fluorescence analysis (XRF) EDXRF vs. WDXRF – The Difference
EDX
WDX
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WDX
• High precision mechanics
• Higher capital
• Precision: <0.05%
• Higher resolution
• Sensitivities: down to the ppm level, but roughly one to two orders more sensitive
• Very fast analysis
• Highest sample throughput
X-ray fluorescence analysis (XRF) The Comparison of Wavelength and Energy Dispersive Spectrometers
EDX • Mechanical simplicity
• Cheaper
• Sensitivities: down to the ppm level
• Easy handling
• Smaller, “can be brought to the sample”
• Less Infrastructure necessary
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The analytical performance of an X-ray
spectrometer is determined by:
• the range of elements
• the separation of elements (“resolution“)
• the sensitivity (kcps/%, cps/ppm)
• the peak to background ratio
• the lower limits of detection
• the reproducibility
These analytical parameters may define which type
of X-ray spectrometer needs to be sold/bought
X-ray fluorescence analysis (XRF)
Which instrument ?
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S2 RANGER • Easy handling
• Easy applications Major, Minor
• Minerals Limestone, Cement, Slags, Glass
• Mining Ores
• Food Milkpowder, Biomass
• Petrochemical Oils, Additives, Minerals
• Coatings & Thin Films Cr passivation
Material specific calibration
Standards (CRMs or inhouse standards)
X-ray fluorescence analysis (XRF) Typical Applications
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S8 TIGER
Standardless Method QUANT-EXPRESS
• Powerful tool for unknown samples
• Liquids, Powder, Pressed Pellet, Bulk samples
• All Materials
• Concentration range low PPM -100%
For highest precision / Trace Analysis
• Material specific calibrations
• Standards (CRMs or inhouse standards)
X-ray fluorescence analysis (XRF) Typical Applications
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S8 TIGER 1K • All applications
• Lower Sensitivity longer measurement time
• Oil, Polymer, Coal
S8 TIGER 3K/4K
• All applications
• Higher Sensitivity High throughput
• Traces in geological samples, Metals, Ferro Alloy
X-ray fluorescence analysis (XRF) Typical Applications
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Examples
Lightweight Matrices
Analysis of lightweight matrices
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Linie Energie
(keV) Graphit Blei
Cd KA1 23.17 cm 14.46 µm 77.30
Mo KA1 17.48 6.06 36.70
Cu KA1 8.05 mm 5.51 20.00
Ni KA1 7.48 4.39 16.60
Fe KA1 6.40 2.72 11.10
Cr KA1 5.41 1.62 7.23
S KA1 2.31 µm 116.00 4.83
Mg KA1 1.25 20.00 1.13
F KA1 0.68 3.70 0.26
N KA1 0.39 0.83 0.07
C KA1 0.28 13.60 0.03
B KA1 0.18 4.19 0.01
Lightweight Matrices
• Organic Samples like Oils/Fuels, Coal, Polymers, Biomass
• Low Matrix Absorption compared to heavier matrices like steel
• saturation depths very high
• Not 100 % Sample can be measured
Sample Thickness has to be considered
Matrix has to be condidered
• Matrix is defined as all Compounds present in the Sample without the Analyte
• In XRF Matrix influence is quite big
• 100 ppm Pb in Polymer Matrix gives a different Intensity as 100 pm Pb in a Fe Matrix
• Influence can be either Absorption or Enhancement
Influence of the Matrix
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Influence of the Matrix Matrix correction – Principle
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Norm Ni
Alpha NiFe
Alpha NiFe,Cr
Stainless Steel
Enhancement ↔ Absorption
Matrix Correction Overview
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Matrix Correction
Modells
Alpha Models
Fixed Alphas
Empirical
By Intensity
by Concentration
Theoretical
Variable Alphas
Internal Standard
By other Element
Compton Normalisation
Heavy Absorber
• Variable Alphas
• Big Concentration Ranges
• Iteration Process
• One Alpha determined for each concentration
• 100 % of sample must be known
• Fixed Alphas
• Theoratical Alphas
• Database Values
• Smaller Concentration Ranges
• 100 % of sample must be known
• Empirical Alphas
• Alphas determined only empirically from the calibration data
• Risky Standards have to be chosen well
• One additional degree of freedom for every correction Many Standards required
Matrix Correction Alpha Correction
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Influence of the Matrix Alpha Models
1
1
where
).1.()..(
thus
.
where
)1.()..(
,
,)(
,
)(
,
,
--
i
j
i
ij
ji
nC
iC
nn
in
jjijLOiii
nn
in
jji
jLOiii
C
CIfImC
CM
MIfImC
ji
ji
a
a
a
Ci = concentration of element i
mi = inverse of the slope
Ii = net intensity for element i
f(LOi,j) = line overlap correction factor
for element j on element i
M = matrix correction
ai,j = matrix correction factor for
element j on i
Cj = concentration of element j
i = mass absorption coefficient of
element i at l of analysed
element
j = mass absorption coefficient of
element j at l of analysed
element
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The regression analysis Calculating the calibration curve
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• Let’s presume a 5 elements matrix
• Through an iteration process the concentrations will be calculated • Best fit for a minimum standard deviation
)1()(
)1()(
)1()(
)1()(
)1()(
,,,,,)(
,,,,,)(
,,,,,)(
,,,,,)(
,,,,,)(
llmkkmjjmiimmimimLOmmm
mmlkkljjliilmimilLOlll
mmkllkjjkiikmimikLOkkk
mmjlljkkjiijmimijLOjjj
mmillikkijjimimiiLOiii
CCCCIfImC
CCCCIfImC
CCCCIfImC
CCCCIfImC
CCCCIfImC
--
--
--
--
--
aaaa
aaaa
aaaa
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aaaa
Influence of the Matrix Matrix correction-Variable Alphas
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Without matrix correction With matrix correction
• Cr in tool steel
Int. korrigiertInt. netto
Inte
nsität
(KC
ps)
Korr
igie
rte I
nte
nsität
(KC
ps)
Konz. (%)
0
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90
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120
0
10
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120
0 1 2 3 4 5 6 7 8 9 10 11
Int. korrigiertInt. netto
Inte
nsität
(KC
ps)
Korr
igie
rte I
nte
nsität
(KC
ps)
Konz. (%)
0
10
20
30
40
50
60
70
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90
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120
0
10
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30
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90
100
110
120
0 1 2 3 4 5 6 7 8 9 10 11
• 0 – 11 % Cr, Std.Dev.: 0.51 % • 0 – 11 % Cr, Std.Dev.: 0.069 %
Anode Coke • Used in Aluminum Industry
• 1 t Aluminium requires 400 kg Anode material
Hall-Heroult-Process • Smelting of Aluminum
• Al2O3 is dissolved in molten Cryolite (Na3AlF6)
• Al3+ is reduced to Al0 at the cathode
Analysis of lightweight matrices Example Anode Coke
CC 3.0 de.wikimedia.org
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Analysis of lightweight matrices Example Anode Coke
Quality Control of Anode Coke
• Analysis of Trace elements
• Used Reference Materials
• S – 0.5 bis 5.0 %
• V – 20 bis 500 ppm
• Ni – 20 bis 500 ppm
• Na – 20 bis 200 ppm
• Ca – 20 bis 200 ppm
• Al – 20 bis 500 ppm
• Fe – 20 bis 500 ppm
• Si – 20 bis 500 ppm
• DIN ISO 12980
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Certified Reference Materials
• 15 Standards
• Certified Values for S, V, Si, Fe, Na, Al, F, Ca, K, Mg, Ba, Cr, Cu, Mn, P, Pb, Sr, Ti, Zn
• Preparation as pressed pellets
• Homogeneous Particle Size Distribution
• Dried at 110C
• 7.0 g Sample + 1.4 g Wax
• Press at 20 t for 20 s
Analysis of lightweight matrices Example Anode Coke
04.12.2014 Workshop XRF Athens – Anne Wegner 45
Conc. XRFInt. net
Inte
nsity (
Cps)
XR
F C
oncentr
ation (
%)
Concentration (%)
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
11000
0
1
2
3
4
0 1 2 3 4
S2 RANGER
• 10 kV, 100 s
• 0.89 – 4.69 %
• LOD: 17 ppm
• R2: 0.9964
Analysis of lightweight matrices Example Anode Coke
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Sulfur (Environmental)
S8 TIGER 1K
• 30 kV, 20 mA, XS-Ge-C, 0.23°
• Max. 6 s
• 0.89 – 4.69 %
• LOD: 15 ppm
• R2: 0.9967
Conc. XRFInt. net
Inte
nsity (
kcps)
XR
F C
oncentr
ation (
%)
Concentration (%)
0
10
20
30
40
50
60
70
80
90
100
110
120
130
0
1
2
3
4
0 1 2 3 4
Conc. XRFInt. net
Inte
nsity (
Cps)
XR
F C
oncentr
ation (
PP
M)
Concentration (PPM)
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
0
10
20
30
40
50
60
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90
100
110
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260
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280
0 100 200
S2 RANGER
• 40 kV, 100 s, Al 500 µm
• 65 – 283 ppm
• LOD: 2.5 ppm
• R2: 0.9981
Nickel (Influence of Al-Quality)
S8 TIGER 1K
• 50 kV, 20 mA, LiF200, 0.23°
• Max. 10 s
• 65 – 283 ppm
• LOD: 1.5 ppm
• R2: 0.9994
Conc. XRFInt. net
Inte
nsity (
kcps)
XR
F C
oncentr
ation (
PP
M)
Concentration (PPM)
0
10
20
30
0
10
20
30
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0 100 200
C set as Matrix
Matrix Correction by variable Alphas used
Reproducibility – S2 RANGER (Measurement Time 12 Minutes)
Analysis of lightweight matrices Example Anode Coke
04.12.2014 Workshop XRF Athens – Anne Wegner 47
Sample S
(%) Ni
(ppm) Si
(ppm) Fe
(ppm) Al
(ppm) V
(ppm) Ca
(ppm) Pb
(ppm) Zn
(ppm) Cr
(ppm) Mn
(ppm) Cu
(ppm)
A509-1 3.01 278 177 216 187 523 49 24 26 11 4 2
A509-2 3.01 279 214 219 192 535 44 25 27 9 4 2
A509-3 3.01 277 202 218 191 525 44 24 27 11 5 3
A509-4 3.00 277 190 214 181 530 44 23 27 12 5 2
A509-5 3.01 281 182 217 186 531 44 24 26 9 3 2
A509-6 3.01 281 178 214 156 527 44 24 27 11 4 2
A509-7 3.01 279 200 217 175 532 44 24 27 9 5 2
A509-8 3.01 282 195 215 193 536 44 25 27 9 4 3
A509-9 3.00 281 195 214 200 535 44 25 27 7 4 2
A509-10 3.02 278 202 214 194 527 44 24 27 10 4 3
Average 3.01 279 193 216 185 530 45 24 27 10 4 2
Std.Dev. 0.010 1.8 11.9 1.9 12.5 4.4 1.4 0.7 0.3 1.4 0.6 0.3
Rel.Std.Dev. 0.21% 0.63% 6.16% 0.88% 6.72% 0.83% 3.14% 2.82% 1.25% 14.65% 13.27% 12.38%
Reproducibility – S8 TIGER 1K (Measurement Time 14 Minutes)
Analysis of lightweight matrices Example Anode Coke
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Sample Na
(ppm)
Mg
(ppm)
Al
(ppm)
Si
ppm)
P
(ppm)
S
(%)
Cl
(ppm)
K
(ppm)
Ca
(ppm)
Ti
(ppm)
Cr
(ppm)
Mn
(ppm)
Fe
(ppm)
Ni
(ppm)
Zn
(ppm)
Pb
(ppm)
B404_F 36 6 43 80 21 0.57 241 13 66 11 9 6 127 3 570 449
B404_F 36 5 48 75 21 0.57 244 14 66 10 9 6 127 3 568 449
B404_F 36 5 45 72 21 0.57 241 13 66 10 9 7 126 3 569 447
B404_F 36 6 46 67 21 0.58 240 13 65 9 9 5 128 4 570 450
B404_F 36 5 47 53 21 0.57 244 14 66 11 9 6 126 3 568 448
B404_F 36 5 46 96 21 0.58 242 15 65 9 9 6 128 4 569 448
B404_F 36 5 45 93 21 0.58 241 14 66 10 9 5 127 4 569 448
B404_F 36 5 46 86 22 0.57 238 14 65 9 9 6 127 3 570 449
B404_F 36 5 45 83 21 0.57 241 14 66 10 9 7 126 3 570 449
B404_F 36 5 43 83 21 0.58 243 14 66 10 9 6 128 4 570 451
Average 36.0 5.2 45.4 78.8 21.1 0.57 241.5 13.8 65.7 9.9 9.0 6.0 127.0 3.4 569.3 448.8
Std.Dev. 0.0 0.4 1.5 12.0 0.3 0.00 1.7 0.6 0.5 0.7 0.0 0.6 0.8 0.5 0.8 1.1
Rel.Std.Dev. 0.00 7.69 3.30 15.29 1.42 0.85 0.72 4.35 0.70 7.07 0.00 10.54 0.61 14.41 0.14 0.24
Lab Report available
• Lab Report XRF 115 Quality control of anode cokes – trace analysis by WDXRF (J. Stelling, K. Behrens)
• S8 TIGER 1K
Lab Report
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Heavy Metals in Soil Overview
• Low levels of heavy elements
• Simple sample preparation
• Measurement time less important
• Availablity of Certified Reference Materials
• Certified Reference Materials pourly described
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Heavy Metals in Soil Concentration Range
Sum below 100 %
No Matrix Correction possible by fundamental Parameters
Use of Rh Compton Normalisation
Sum(%) V(PPM) Cr(PPM) MnO(PPM) Fe2O3(%) Co(PPM) Ni(PPM) Cu(PPM)
Min 0,18 0 0 201 1,9 0 0 0
Max 100 109 110 111 112 113 114 115
As(PPM) Rb(PPM) Sr(PPM) Y(PPM) Zr(PPM) Mo(PPM) Cd(PPM) Ba(PPM)
Min 0 41 28 13 110 1 0 185
Max 118 119 120 121 122 123 124 126
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Compton Normalisation Properties – Compton & Rayleigh
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• Elastic scattering • no energy loss after collision
of electrons
• Rayleigh effect is present
when electrons are strongly
bound
• Rayleigh is more present in
heavy matrices
• Inelastic scattering • energy loss after collision of
electrons
• Compton effect is present
when electrons are loosely
bound
• Compton is more present in
light matrices
l𝒄 > l𝒄 = l𝟎
01
02
03
04
05
06
07
08
09
01
00
11
01
20
13
01
40
15
01
60
17
01
80
19
02
00
21
02
20
23
02
40
25
02
60
27
02
80
KC
ps
1718192021222324
KeV
Physics of X-rays Properties – Compton & Rayleigh
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0.033 Å
l𝒄 − l𝟎 = 𝟎. 𝟎𝟐𝟒𝟑(𝟏 − 𝒄𝒐𝒔 )
= 108° l𝒄 − l𝟎 = 𝟎. 𝟎𝟑𝟑 Å
Compton Peaks From Different Samples
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• Scattered characteristic radiation from
the tube’s anode
• A measure for the sample’s matrix
• As average atomic number decreases,
Compton intensity increases
• Water (H2O) has an average atomic number
of 3.3
• Ethanol (C2H5OH) has an average atomic
number of 2.9
• Oil (CH2) has an average atomic number of
2.7
• C. factor = calculated C./measured C.
• Should be close to 1
• Use to adapt the matrix
Heavy Metals in Soil Example Fe
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• Measurement Conditions
• Preparation Loose Powder 4 µm Prolene
• Atmosphere Helium
• Analysis Time approx. 20 min
• Special Crystal recommended LiF220
01
23
45
10
20
30
40
50
60
70
80
90
100
110
KC
ps
Rb K
A1
Rb K
B1 A
s K
B1
Sr
KA
1
Sr
KB
1Z
r K
A1
Zr
KB
1
Pb L
B1
Mo K
A1
11121314151617
KeV
Heavy Metals in Soil Example Fe
• SD = 0,27 %
• R² = 0,991
• LLD = 30 ppm
• SD = 0,46
• R² = 0,95
• LLD = 34 ppm
Konz. RFA
RF
A K
onzentr
ation (
%)
Konz. (%)
0
1
2
3
4
5
6
7
8
9
0 10 20 30 40 50 60 70 80 90 100
Konz. RFA
RF
A K
onzentr
ation (
%)
Konz. (%)
0
1
2
3
4
5
6
7
8
9
10
11
0 10 20 30 40 50 60 70 80 90 100
With Compton Normalisation Without Compton Normalisation
04.12.2014 56 Workshop XRF Athens – Anne Wegner
Heavy Metals in Soil Example Pb
• SD = 41 ppm
• R² = 0,996
• LLD = 2,4 ppm
• SD = 11 ppm
• R² = 0,9997
• LLD = 3 ppm
Konz. RFA
Konzentr
ation (
PP
M)
Konz. (%)
0
1000
2000
3000
0 10 20 30 40 50 60 70 80 90 100
Konz. RFA
Konzentr
ation (
PP
M)
Konz. (%)
0
1000
2000
3000
0 10 20 30 40 50 60 70 80 90 100
With Compton Normalisation Without Compton Normalisation
04.12.2014 57 Workshop XRF Athens – Anne Wegner
Heavy Metals in Soil Example Al
• SD = 1,15
• R² = 0,97
• LLD = 228 ppm
• SD = 2,09 %
• R² = 0,93
• LLD = 0,2 %
With Compton Normalisation Without Compton Normalisation
Konz. RFA
RF
A K
onzentr
ation (
%)
Konz. (%)
0
10
20
30
0 10 20 30 40 50 60 70 80 90 100 Konz. RFA
RF
A K
onzentr
ation (
%)
Konz. (%)
0
10
20
30
0 10 20 30 40 50 60 70 80 90 100
04.12.2014 58 Workshop XRF Athens – Anne Wegner
Example Quadratic Correlation-Electroplating
Electroplating
• Use Elecrical current to reduce the cations from the solution
• Coating on Electrode
• Cu needs to be determined in Cu-Sulphate bath
• Pretty high concentrations
• Low No. of Elements (S, Cu) inside the sample
• No high resolution necessary
• Energy dispersive XRF can be
used
CC 3.0 de.wikimedia.org
04.12.2014 59 Workshop XRF Athens – Anne Wegner
Example Quadratic Correlation-Electroplating
Cu(%) H2O(%)
Kal 1 4,6 80,4
Kal 2 5,12 79,88
Kal 3 5,65 79,35
Cu Bad_Blank 0 100
Kal 1 1-1 2,31 90,16
Kal 2 1-1 2,57 89,9
Kal 3 1-1 2,82 89,65
Kal 2 1-7 0,73 100
Kal 3 1-7 0,81 100
• Measurement Conditions
• Analysis Time < 5 min
• Voltage 40 kV
• Current Automatic
• Filter 500 µm Al
04.12.2014 60 Workshop XRF Athens – Anne Wegner
Example Quadratic Correlation-Electroplating
• SD = 0,49 %
• R² = 0,96
• LLD = 7 ppm
• SD = 0,029 %
• R² =0,9998
• LLD = 4,4 ppm
Conc. XRFInt. net
Inte
nsity
(C
ps)
XR
F C
once
ntra
tion
(%)
Concentration (%)
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
0
1
2
3
4
0 1 2 3 4 5
Conc. XRFInt. net
Inte
nsity
(C
ps)
XR
F C
once
ntra
tion
(%)
Concentration (%)
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
0
1
2
3
4
5
0 1 2 3 4 5
04.12.2014 61 Workshop XRF Athens – Anne Wegner
• Excellent Calibration Curve
• 10-fold Preparation delivers excellent reproducibilty
Example Quadratic Correlation-Electroplating
Sample Cu (%)
Cu-Bath 1 4,471
Cu-Bath 2 4,472
Cu-Bath 3 4,47
Cu-Bath 4 4,473
Cu-Bath 5 4,475
Cu-Bath 6 4,465
Cu-Bath 7 4,468
AV 4,471
SD 0,003
RSD 0,074
04.12.2014 62 Workshop XRF Athens – Anne Wegner
Example Ni and Cr in potable Water
• Cr
• Concentration Range 1-10 ppm
• SD = 0,1 ppm
• LLD = 0,7 ppm
Conc. XRFInt. net
Inte
nsity
(C
ps)
XR
F C
once
ntra
tion
(PP
M)
Concentration (PPM)
-0,1
0
0,1
0,2
0,3
0
1
2
3
4
5
6
7
8
9
10
0 1 2 3 4 5 6 7 8 9 10
Conc. XRFInt. net
Inte
nsity
(C
ps)
XR
F C
once
ntra
tion
(PP
M)
Concentration (PPM)
0
1
2
3
4
0
1
2
3
4
5
6
7
8
9
10
0 1 2 3 4 5 6 7 8 9 10
• Ni
• Concentration Range 1-10 ppm
• SD = 0,1 ppm
• LLD = 0,1 ppm
04.12.2014 63 Workshop XRF Athens – Anne Wegner
Analysis of Geological Samples
XRF Applications for Geology, Mining, Minerals, Ceramics
• Wide range of XRF applications for
• Geological Surveys
• Mining: Exploration and Exploitation
• Industrial Minerals
• Cement: Raw Materials
• Ceramics and Refractories
• Glass
• Technical oxides: Fluid cracking catalysts (FCC) for petro industry
• Analysis of major and minor elements as oxides
• for grade control and product quality (purity) based on fused beads
• Analysis of traces
• for purity control and geological and environmental mapping based on pressed pellet
04.12.2014 65 Workshop XRF Athens – Anne Wegner
S8 TIGER GEO-QUANT M
• The advanced analytical
• solution for the accurate and
• precise analysis of major and
• minor elements developed for
• various XRF applications such
• as:
• Geology
• Mining
• Industrial minerals
• Exploration
• Exploitation
• Ceramics
• Refractories
• Glass
04.12.2014 66 Workshop XRF Athens – Anne Wegner
S8 TIGER GEO-QUANT M
• Reference calibration based on more than 20 certified reference materials:
• for 11 elements as oxides: Na2O, MgO, Al2O3, SiO2, P2O5, SO3, K2O, CaO, TiO2 MnO, Fe2O3
• matrix correction based on variable alpha model
• measurement time:
• 6 min for the default program S8 TIGER 4 K
• optimized sample preparation procedure as fused beads
• For optimum results of P and S:
• XS-GE-C
04.12.2014 67 Workshop XRF Athens – Anne Wegner
GEO-QUANT M Accurate and precise
Element
Low range
[%]
High range
[%]
Na2O 0.01 11.30
MgO 0.01 95.77
Al2O3 0.04 90.80
SiO2 0.41 99.88
P2O5 0.01 19.34
SO3 0.05 54.38
K2O 0.01 15.36
CaO 0.01 97.88
TiO2 0.01 7.79
MnO 0.01 0.88
Fe2O3 0.01 39.08
04.12.2014 68 Workshop XRF Athens – Anne Wegner
Wide calibration ranges
• Close to 100 % for most of the
elements
• best practice: based on fusion
sample preparation for accurate
results
• enhanced evaluation based on
unique matrix correction with the
variable alpha model
• intelligent measurement strategy for
high sample throughput and
shortest time-to-results
GEO-QUANT M Accurate and precise
04.12.2014 69 Workshop XRF Athens – Anne Wegner
Accurate calibrations for major oxides based on
fusion beads for best precision
Coverage of wide concentration ranges and materials
GEO-QUANT M The perfect match
04.12.2014 70 Workshop XRF Athens – Anne Wegner
0
20
40
60
80
100
0 10 20 30 40 50 60 70 80 90 100
SiO2 % (measured)
SiO
2 %
(c
ert
ific
ati
on
)
Evaluation of the accuracy for a wide range of
international reference materials
(Acceptance test samples included shown in yellow)
GEO-QUANT M The perfect match – again and again
Na2O MgO Al2O3 SiO2 P2O5 SO3 K2O CaO TiO2 MnO Fe2O3
certificate 1,48 2,59 19,18 63,23 0,18 0,41 3,13 2,06 0,80 0,09 7,06
Precision test 20 times alternated measurement
average 1,40 2,49 19,16 63,45 0,18 0,46 3,14 1,91 0,79 0,09 6,95
min. 1,39 2,47 19,13 63,32 0,18 0,45 3,14 1,91 0,78 0,09 6,94
max. 1,42 2,50 19,20 63,52 0,18 0,46 3,15 1,92 0,79 0,09 6,97
std. dev. 0,01 0,01 0,02 0,05 0,00 0,00 0,00 0,00 0,00 0,00 0,01
relative SD 0,52 0,40 0,10 0,07 0,00 0,49 0,10 0,19 0,56 0,00 0,10
repeatability test 18 measurement during 30 Days
average 0,11 0,36 64,26 17,88 0,27 0,20 0,39 2,71 2,91 0,04 10,49
min. 0,10 0,36 64,15 17,82 0,27 0,20 0,39 2,71 2,90 0,04 10,46
max. 0,12 0,37 64,36 17,92 0,28 0,21 0,39 2,72 2,91 0,04 10,53
std. dev. 0,01 0,00 0,05 0,03 0,00 0,01 0,00 0,00 0,00 0,00 0,02
relative SD 5,91 0,79 0,08 0,16 1,65 2,48 0,11 0,16 0,12 3,60 0,20
04.12.2014 71 Workshop XRF Athens – Anne Wegner
GEO-QUANT M Turn-Key Solution for the S8 TIGER
04.12.2014 72 Workshop XRF Athens – Anne Wegner
• The complete solution for
• the process and quality control
• by XRF for general oxides:
• Geological materials
• Industrial Minerals
• Ceramics, Refractories, Glass
• Including:
• 20 standard reference materials
• 3 acceptance test samples
• 3 glass drift monitor samples
• Operators manual
• Sample preparation manual
• Material safety data sheets
S8 TIGER GEO-QUANT T
• the trace element solution developed for various geological applications such as:
• limestone
• soils
• sediments
• industrial minerals
• ceramics
• in
• research
• monitoring
• exploration
04.12.2014 73 Workshop XRF Athens – Anne Wegner
S8 TIGER GEO-QUANT T
• Mastercalibration based on hundreds international certified reference materials:
• For 27 Elements: TiO2, MnO, Fe2O3, Sc, V, Cr, Co, Ni, Cu, Zn, Ga, As, Rb, Sr, Y, Zr, Nb, Mo, Sn, Sb, Cs, Ba, La, Ce, Pb, U, Th
• Automatic matrix correction
• Measurement time:
• typically 38 min for the default program S8 TIGER
• Optimized background handling with shared positions
• Optimized sample preparation procedure
04.12.2014 74 Workshop XRF Athens – Anne Wegner
Hunting for Traces in Geology Measurement method
Upper calibration range • Up to 3500 ppm
Matrix elements • TiO2, Fe2O3 and MnO calibrated up
to the % range to be used for the correction of interferences
• Automatic matrix correction based of Rh Compton method
Measurement time • 20 – 100 s • (counting statistical
optimization) Typical LOD • Down to the sub-ppm range
04.12.2014 75 Workshop XRF Athens – Anne Wegner
Hunting for Traces in Geology Master calibration Sr
04.12.2014 76 Workshop XRF Athens – Anne Wegner
Sr
Range : - 1500 ppm
LOD : 0.8 ppm
Std.Dev.: 5.9 ppm
Hunting for Traces in Geology Master calibration Pb
04.12.2014 77 Workshop XRF Athens – Anne Wegner
Pb
Range : - 2500 ppm
LOD : 1.4 ppm
Std.Dev.: 6.1 ppm
Hunting for Traces in Geology Optimized background handling
Shared background positions
• to modelize background
• to minimize measurement time
04.12.2014 78 Workshop XRF Athens – Anne Wegner
S8 TIGER GEO-QUANT M & T: User Benefits
• quantitative elemental analysis
• as easy as possible
• Well defined sample preparation methods
• Simple start of measurements
• accurate and precise analysis results
• right out of the box
• Ready-to-analyze for a wide range of geological trace applications
• A minimum of operator training required
• GEO-QUANT runs over years
• saves time and money!
• Quick start directly after installation
• no suite of expensive standards is needed
• No need for weeks of method development
04.12.2014 79 Workshop XRF Athens – Anne Wegner
Innovation with Integrity
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