cement by xrf

Global Cement and Raw Materials Fusion/XRF Analytical

Solution

Mathieu Bouchard, John Anzelmo, and Sebastien RivardCorporation Scientifique Claisse, Quebec, Canada

Alexander Seyfarth and Larry AriasBruker-AXS, Madison, WI

Kai Behrens and Soodabeh Durali-M��Bruker-AXS GmbH, Karlsruhe, Germany

ABSTRACT

A robust analytical method using an automated fusion machine as sample preparationtool and a wavelength-dispersive X-ray fluorescence spectrometer for the determinationof all the elements of interest for the cement industry has been developed. This methodwas used to prepare all cements, all process materials, and a very large range of rawmaterials. The choice of all fusion parameters and all XRF analysis conditions, includingcalibration corrections, are shown. Two sets of reference materials (RM) from twodifferent sources were used to verify that this fusion method allows a matrix match forcement from different origins. One set is from the National Institute of Standards andTechnology (NIST) and the other set is from the Japan Cement Association (JCA). Acritical evaluation of precision and accuracy has been performed against standardmethods from two well known international reference organizations: The AmericanSociety for Testing and Materials International (ASTM) and the InternationalOrganization for Standardization (ISO). The two standard methods for analysis ofcement by X-ray fluorescence are known as: ASTM C 114 [1] and ISO/DIS 29581-2 [2].Qualification of reference materials not included in the calibration is also investigated.

INTRODUCTION

For the last five decades, X-ray fluorescence spectrometry has been widely accepted asthe standard method for quantitative chemical analysis of cement industry samples. Inthe past, sample preparation by both pressed powder and fusion were accepted for thoseanalyses [3]. The 21st century reality of the cement industry with the increase ofproduction of cements with alternative raw materials and additives involving secondaryfuels, and the use of reference materials from various sources in the world, make the useof pressed powder more complicated because of the necessity for matrix matching toincrease or optimize the accuracy with this analytical technique. The use of the fusionpreparation technique requires less calibration curves because this method removesparticle size and mineralogy effects [3, 4]. For those reasons a global and unique fusionmethod for the preparation of all cements, all process materials, and a very large range ofraw materials is desirable, when combined with wavelength-dispersive X-rayfluorescence (WDXRF), to allow compliance with the ASTM C 114 and ISO/DIS 29581-2 specifications of precision and accuracy.

263Copyright ©-International Centre for Diffraction Data 2010 ISSN 1097-0002

To develop a fusion method for sample preparation, with such a wide range of differentmaterials with various compositions, many parameters were evaluated. The list ofmaterials that were investigated were the following: cement, blended cement, cementswith additions, aluminate cement, clinker, kiln feed, raw mix, limestone, gypsum, sand,clay, bauxite, silica fume, slag, fly ash, iron ore and others. Because the fusion processhas a history of more than 50 years, some of the parameters are well known. Parameterssuch as type of material for crucible and molds, composition of flux, type and amount ofnon-wetting agent to use, and maximum fusion temperature are well known, andincorporated with an automated fusion machine for excellent precision and stability overtime. Nevertheless, a global solution still requires refinement of the various parameters.The list of all parameters that were evaluated for this project was:

- Calcinations and/or lost on ignition (LOI)) at various temperatures- Effective way to prepare the mix in the crucible- Fusion time- Agitation speed at various stages of the process- Best sample to flux ratio- Dry oxidation process and selection of oxidizer- Cooling speed and time

EXPERIMENTAL

-Apparatus and instrumental conditions

A Claisse M4� propane fired automatic fluxer was used to generate all fusion beads. AFisher Scientific Isotemp�� for the LOIdeterminations and preparation of ignited samples. The LOI method used for all cementtypes and clinker included ignition at 950��in a clean Pt crucible for 60 minutes. Thisfirst method meets ASTM and ISO requirements for LOI determination. Becausematerial which contained under oxidized compounds could destroy platinum ware, asecond LOI method for those materials was incorporated called LOI until constant weigh.The sample was weighed precisely in a clean and ignited ceramic crucible, then ignited at950�� , then cooled and weighed. Thereafter, the sample is ignited bysequences of 15 minutes in the furnace at the same temperature, 30 minutes of coolingand weighing. A constant weigh is considered when two successive weighings give aresult with a difference of less than 0.0005g.

A Bruker-AXS S4 Explorer sequential wavelength-dispersive X-ray spectrometer with an82 position automatic sample changer and a rhodium end-window X-ray tube was usedfor data generation. Spectrometer analytical conditions, peak-line, backgroundmeasurements, background position, pulse-height, counting time and others were selectedand optimized by wavelength step-scanning of selected standard disks. The ISOvalidation test for repeatability of the spectrometer was used to verify properspectrometer operation and to optimize the counting time for the peaks. The


spectrometer analytical conditions for the measurement of all elements are listed in Table1. A 28 mm collimator mask and vacuum were used for all measurements.

Table 1. Spectrometer Operation Parameters

Element kV mA Crystal Collimator Detectora

Peak Peak Time Low bkdb

High bkdb

Bkd Time

(�� (�� (Ao) (s) (�� (�� (s)

Al K� 40 25 PET 0.46 FPC 144.617 8.3393 80.0 --- --- ---Ca K� 40 25 LiF200 0.23 FPC 113.086 3.3584 32.0 --- --- ---Cr K� 40 25 LiF200 0.23 SC 69.358 2.2897 12.0 68.567 70.156 12.0Fe K� 40 25 LiF200 0.23 SC 57.520 1.936 6.0 --- --- ---K K� 40 25 LiF200 0.46 FPC 136.647 3.7414 24.0 --- --- ---Mg K� 40 25 XS-55 0.46 FPC 20.602 9.893 64.0 --- --- ---Mn K� 40 25 LiF200 0.23 SC 62.984 2.1018 6.0 61.524 63.867 6.0Na K� 40 25 XS-55 0.46 FPC 24.825 11.91 96.0 --- 26.384 96.0P K� 40 25 Ge 0.46 FPC 140.959 6.157 10.0 --- 143.315 10.0S K� 40 25 Ge 0.46 FPC 110.646 5.3722 40.0 --- --- ---Si K� 40 25 PET 0.46 FPC 108.998 7.1254 120.0 --- --- ---Sr K� 40 25 LiF200 0.23 SC 25.145 0.87526 6.0 24.555 25.779 6.0Ti K� 40 25 LiF200 0.46 FPC 86.165 2.7485 6.0 --- 88.299 6.0Zn K� 40 25 LiF200 0.23 SC 41.809 1.4352 6.0 41.170 42.436 6.0

a FPC = gas flow proportional counter; SC = scintillation counterb Low bkd and high bkd = value for lower and higher background when used

-Fusion method development

To develop this global fusion method both ignited and non ignited materials were fused.Different dry oxidation processes on the fluxer were tried with different oxidizers. Threeways to prepare the sample and flux mix in the crucible were tried. Different sample toflux ratios were tried (1:6, 1:8 and 1:10). For the preferred ratio which is 1:10 differenttotal amounts of preparation were evaluated.

-Global sample preparation method

An Optimix* crucible and a 32 mm diameter, 1 mm thick mold was used to eliminate thecurvature effect, which can occur after multiple heating cycles. Pure grade pre-fusedflux* composition of 49.75% lithium tetraborate (LiT), 49.75% lithium metaborate (LiM),containing integrated 0.50% LiBr non-wetting agent was selected to increase thehomogeneity and make stable glass disks. The maximum fusion temperature used forthis fusion is 1050�� ritical temperature, flux beginsto volatilize without consistency which changes the sample to flux ratio [5]. Othercompounds like SO3 begin to volatilize without consistency as well [4].

-Results of fusion method development

It was determined that ignition of the sample is absolutely necessary in the analyticalprocess for a global fusion method. This critical step allows fusion of the raw materialsand cements with additions, which are difficult or impossible to fuse in the non-ignitedstate. A preparation with a ratio of 1:10 with 6.600g of total mass takes a fusion program

* Available at Corporation Scientifique Claisse www.claisse.com


of 13 minutes heating at 1025�� to prepare stable glass disks with high alumina and/orhigh silica samples. The mold is automatically heated in the flame before the pouringstep. The cooling process is done with forced air for 5 minutes.

-Step by step procedure

First 0.6000g of ignited sample is weigh with �� !� �� in a clean and dryOptimix Pt/Au crucible. Then, 6.0000g of Claisse LiT/LiM/LiBr: 49.75/49.75/0.50, PureGrade Flux is weighed with �� g precision on top of the sample. A mini-vortexmixer is used to mix the sample with the flux. The mini-vortex mixer speed wascontrolled so as not to lose material, because variance from the ratio of flux to sampleweight causes error in the results [6]. All parameters set for this fusion program on theM4 fluxer are shown in table 2.

Table 2. Automatic fusion program parameters

F0 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13Heating Heating Heating Heating Heating Heating Heating Heating Pouring Cooling Cooling Cooling Cooling Cooling

Gas 10 10 20 30 65 65 20 55 50 00 00 00 00 00Crucible Speed 00 00 00 00 00 50 20 00 10 00 00 00 00 00Time (mm:ss) 00:05 00:05 00:05 00:05 04:30 07:00 00:15 00:30 00:35 00:05 00:10 00:10 00:10 04:15Arm Position 00 10 20 30 35 35 20 42 55 30 20 10 00 00Mold Arm Position 00 00 00 00 00 00 00 00 95 20 20 20 20 20Fan Speed 00 00 00 00 00 00 00 00 00 99 99 99 99 99

Step


-Robustness of the fusion method

More than 200 different samples from the 20 material types were fused with the globalfusion method. The materials are listed in table 3. This list included materials notcommonly used as raw materials, but sometimes found in waste materials used as fuel, totest the limits of the global nature of the method.

Table 3. List of Materials used in this experiment

Material Types Fused with Sucess Fusion Failed Total Number

with the Method of Sample Tried

Cement 110 0 110Cement with Additions

a 15 0 15Aluminate Cement 7 0 7Clinker 13 0 13Kiln Feed/Raw Mix 11 0 11Limestone 5 0 5Gypsum 4 0 4Sand 7 0 7Clay 5 0 5Bauxite 3 0 3Silica Fume 2 0 2Slag

b 5 2 7Fly Ash 4 0 4Coal Ash 1 0 1Iron Ore

c 7 6 13Basalt 1 0 1Chalcopyrite

d 0 1 1Jarosite

e 1 0 1Soil and Sediment 2 0 2Unknown 2 0 2

Total 205 9 214

a Only the cements with known additions are listed here; the cement category probably included somecements with additionsb The two slag samples that failed contained copperc The iron ore samples that failed contained magnetite and/or high iron concentrationd Chalcopyrite is an iron ore containing coppere Jarosite is an iron ore containing potassium

The Global Fusion Method showed good efficiency to prepare homogenous and stablelithium borate glass disks with all of the materials except three: chalcopyrite, high ironore and copper slag.


-Preparation for calibration, selection of control samples and preparation forvalidation

As discussed previously one objective of this project was to calibrate the WDXRF withtwo sets of RM from different origins: NIST Standard Reference Material� (SRM)Series 1880a, 1881a and 1884a to 1889a, and JCA Reference Materials for X-rayFluorescence Analysis 601A Series XRF-01 to XRF-15. The second objective was tocomply with the requirements of ASTM and ISO standard methods for analysis ofcement. Those standard methods have two different philosophies. ASTM uses SRM��verify precision and accuracy on two different days [1]. ISO validates repeatability of themethod using one or more RM��, as control samples that are not included in thecalibration over at least two weeks [2]. An important thing to note is that for verificationof ASTM requirements, results should include LOI, and for ISO, LOI free results areneeded. Table 4 shows the element concentration range as oxide equivalent for both RMsets and for the combination of the two sets. This table also shows the elementconcentration of the two control samples selected to evaluate the global fusion/XRFmethod with ISO standard method.

Table 4. RM element concentration as oxide equivalent and control samples

Elements

JCA XRF-03 JCA XRF-14

SiO2 (%) 18.907 - 22.73 20.52 - 29.29 18.907 - 29.29 20.67 25.74

Al2O3 (%) 3.936 - 7.174 3.40 - 10.70 3.40 - 10.70 4.57 8.70

Fe2O3 (%) 0.154 - 3.14 1.32 - 4.18 0.154 - 4.18 2.43 2.03

CaO (%) 58.51 - 68.94 49.28 - 66.32 49.28 - 68.94 66.32 55.15

MgO (%) 0.842 - 4.523 0.78 - 5.12 0.78 - 5.12 1.53 3.98

SO3 (%) 2.119 - 4.689 1.91 - 3.18 1.91 - 4.689 3.18 N/A

Na2O (%) 0.021 - 1.086 0.10 - 0.38 0.021 - 1.086 0.30 0.26

K2O (%) 0.094 - 1.248 0.23 - 0.62 0.094 - 1.248 0.45 0.31

TiO2 (%) 0.085 - 0.3722 0.16 - 0.73 0.085 - 0.73 0.28 0.66

P2O5 (%) 0.022 - 0.310 0.04 - 0.40 0.022 - 0.40 0.13 0.04

Mn2O3 (%) 0.0074 - 0.2676 0.06 - 0.68 0.0074 - 0.68 0.09 0.31

SrO (%) 0.018 - 0.649 0.024 - 0.071 0.018 - 0.649 0.049 0.051

Cr2O3 (%) 0.0024 - 0.0597 N/A - N/A 0.0024 - 0.0597 N/A N/A

ZnO (%) 0.001 - 0.109 N/A - N/A 0.001 - 0.109 N/A N/A

Concentration Range

NIST

(LOI Free Base)

Concentration Range

JCA

(LOI Free Base)

Concentration Range

NIST & JCA

(LOI Free Base)

ISO Control Samplesa

(LOI Free Base)

a Control samples: One or more certified RM, not used in the calibration and having a composition withinthe calibration range for each element to be analyzed. When only one validation certified RM is to be used,select a sample in the middle of the concentration ranges. Where several validation certified RM�� used, select samples covering high and low values [2].

For the calibration of the XRF instrument and for validation of the Global Fusion/XRFmethod with ASTM Standard Test Method C 114, two set of glass disks were preparedfor every RM, one on the first day and the second on the next day, not less than 24 hoursapart. For validation of the analytical method with ISO 10 glass disks of every controlsamples (JCA XRF-03 and JCA XRF-14) were prepared over 15 days (not less then 2weeks). The control sample glass disks were run on the same day they were prepared.


RESULTS AND DISCUSSION

-Calibration

All of the NIST and JCA Reference Materials (except the control samples) were used inthe calibration. Table 5 shows for which element inter-element corrections were usedand which type. This table also shows the squared correlation coefficients from thecalibration curves of all analyzed elements. This tool shows that this sample preparationmethod eliminates the effect of different matrix from different origins, because all resultsare very close to 1. These results confirm that the validation of the global fusion/XRFanalytical method against the previously mentioned ASTM and ISO standard methodscould now proceed.

Table 5. Inter-element correction and squared correlation coefficients for allcalibration curves

Element Inter-element Squared

correction Correlation

information Coefficient

Al K� Fixed Alphas 0.9999Ca K� Fixed Alphas 0.9998Cr K� No Correction 0.9958Fe K� Fixed Alphas 0.9998K K� Fixed Alphas 0.9997Mg K� Fixed Alphas 0.9999Mn K� No Correction 0.9990Na K� No Correction 0.9975P K� Fixed Alphas 0.9978S K� Fixed Alphas 0.9984Si K� Fixed Alphas 0.9995Sr K� No Correction 0.9998Ti K� Fixed Alphas 0.9981Zn K� No Correction 0.9996


-ASTM Precision and accuracy

The ASTM precision test was applied as it is described in method [1]. The duplicates arethe two disks prepared on two different days for every RM. The results shown in tables6 and 7 are the absolute difference of the results of duplicate for all analyzed element.The maximum difference for all elements is shown and compared to the ASTM precisionlimit. The maximum values obtained for all elements meet the specifications and wellwithin the limits.

Table 6. ASTM C114: Precision Test Results (Part 1)

Calibrated SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2O K2O

RM (%) (%) (%) (%) (%) (%) (%) (%)

NIST 1880a 0.080 0.022 0.012 0.058 0.012 0.017 0.005 0.007NIST 1881a 0.011 0.006 0.001 0.001 0.007 0.048 0.005 0.012NIST 1884a 0.033 0.018 0.000 0.075 0.002 0.013 0.001 0.002NIST 1885a 0.010 0.033 0.008 0.067 0.013 0.021 0.007 0.001NIST 1886a 0.012 0.009 0.001 0.040 0.008 0.029 0.005 0.001NIST 1887a 0.045 0.026 0.010 0.078 0.032 0.048 0.001 0.009NIST 1888a 0.035 0.021 0.012 0.122 0.031 0.018 0.004 0.006NIST 1889a 0.011 0.006 0.007 0.004 0.003 0.012 0.006 0.000JCA-XRF-01 0.085 0.019 0.004 0.104 0.007 0.001 0.010 0.001JCA-XRF-02 0.016 0.011 0.001 0.007 0.012 0.001 0.009 0.001JCA-XRF-04 0.053 0.024 0.013 0.114 0.009 0.010 0.004 0.001JCA-XRF-05 0.010 0.005 0.008 0.026 0.000 0.009 0.006 0.001JCA-XRF-06 0.021 0.004 0.004 0.131 0.001 0.033 0.010 0.003JCA-XRF-07 0.022 0.014 0.007 0.121 0.010 0.008 0.000 0.003JCA-XRF-08 0.061 0.014 0.008 0.051 0.003 0.017 0.007 0.003JCA-XRF-09 0.015 0.019 0.003 0.075 0.006 0.002 0.003 0.002JCA-XRF-10 0.012 0.002 0.001 0.056 0.002 0.008 0.007 0.003JCA-XRF-11 0.004 0.008 0.004 0.087 0.015 0.028 0.011 0.001JCA-XRF-12 0.017 0.012 0.013 0.019 0.004 0.001 0.004 0.001JCA-XRF-13 0.003 0.019 0.007 0.007 0.009 0.002 0.003 0.001JCA-XRF-15 0.027 0.036 0.007 0.013 0.002 0.014 0.001 0.004Max Value 0.085 0.036 0.013 0.131 0.032 0.048 0.011 0.012

ASTM Limit 0.16 0.20 0.10 0.20 0.16 0.10 0.03 0.03

Control SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2O K2O

Samplesa

(%) (%) (%) (%) (%) (%) (%) (%)

JCA-XRF-03 0.010 0.003 0.003 0.026 0.003 0.020 0.006 0.006JCA-XRF-14 0.017 0.013 0.008 0.028 0.018 0.027 0.002 0.003

a Results of control samples are include in the calculation for Max Value


Table 7. ASTM C114: Precision Test Results (Part 2)

Calibrated TiO2 P2O5 Mn2O3 SrO Cr2O3 ZnO Sum

RM (%) (%) (%) (%) (%) (%) (%)

NIST 1880a 0.0090 0.0009 0.0018 0.0016 0.0005 0.0014 0.130NIST 1881a 0.0085 0.0022 0.0009 0.0008 0.0018 0.0036 0.040NIST 1884a 0.0036 0.0022 0.0053 0.0010 0.0005 0.0019 0.100NIST 1885a 0.0069 0.0021 0.0016 0.0007 0.0004 0.0009 0.000NIST 1886a 0.0062 0.0045 0.0011 0.0002 0.0002 0.0002 0.030NIST 1887a 0.0037 0.0067 0.0058 0.0016 0.0003 0.0021 0.150NIST 1888a 0.0115 0.0027 0.0046 0.0009 0.0018 0.0019 0.210NIST 1889a 0.0074 0.0027 0.0058 0.0001 0.0010 0.0001 0.010JCA-XRF-01 0.0054 0.0009 0.0035 0.0015 0.0024 0.0011 0.190JCA-XRF-02 0.0037 0.0055 0.0007 0.0001 0.0017 0.0001 0.040JCA-XRF-04 0.0046 0.0026 0.0009 0.0017 0.0011 0.0029 0.230JCA-XRF-05 0.0104 0.0055 0.0069 0.0009 0.0005 0.0025 0.010JCA-XRF-06 0.0018 0.0039 0.0002 0.0000 0.0031 0.0010 0.200JCA-XRF-07 0.0124 0.0009 0.0008 0.0017 0.0015 0.0016 0.120JCA-XRF-08 0.0140 0.0003 0.0017 0.0001 0.0015 0.0004 0.150JCA-XRF-09 0.0004 0.0063 0.0030 0.0006 0.0004 0.0005 0.060JCA-XRF-10 0.0059 0.0077 0.0038 0.0021 0.0015 0.0007 0.090JCA-XRF-11 0.0037 0.0113 0.0028 0.0008 0.0005 0.0015 0.130JCA-XRF-12 0.0011 0.0038 0.0035 0.0006 0.0017 0.0011 0.000JCA-XRF-13 0.0020 0.0003 0.0088 0.0027 0.0002 0.0014 0.000JCA-XRF-15 0.0063 0.0005 0.0035 0.0023 0.0008 0.0008 0.010Max Value 0.0140 0.0113 0.0088 0.0027 0.0031 0.0036 0.230

ASTM Limit 0.02 0.03 0.03 --- --- 0.03 ---

Control TiO2 P2O5 Mn2O3 SrO Cr2O3 ZnO Sum

Samplesa

(%) (%) (%) (%) (%) (%) (%)

JCA-XRF-03 0.0115 0.0074 0.0004 0.0004 0.0008 0.0005 0.060JCA-XRF-14 0.0058 0.0028 0.0011 0.0016 0.0003 0.0014 0.100

a Results of control samples are include in the calculation for Max Value


The ASTM accuracy test was applied as it is described in method [1]. The results shownin tables 8 and 9 are the absolute difference of the average of duplicates from the RMcertified values for all analyzed elements. The absolute maximum error for all elementsis shown and compared to the ASTM accuracy limit. The maximum values obtained forall elements meet the specifications and well within the limits.

Table 9. ASTM C114: Accuracy Test Results (Part 1)

Calibrated SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2O K2O

RM (%) (%) (%) (%) (%) (%) (%) (%)

NIST 1880a 0.000 0.045 0.018 0.046 0.000 0.051 0.006 0.005NIST 1881a 0.050 0.017 0.005 0.034 0.027 0.001 0.004 0.005NIST 1884a 0.009 0.019 0.050 0.092 0.003 0.001 0.003 0.003NIST 1885a 0.023 0.005 0.020 0.044 0.004 0.006 0.005 0.004NIST 1886a 0.080 0.023 0.005 0.115 0.007 0.006 0.010 0.002NIST 1887a 0.063 0.004 0.003 0.011 0.017 0.019 0.002 0.004NIST 1888a 0.005 0.051 0.025 0.031 0.016 0.057 0.029 0.001NIST 1889a 0.003 0.060 0.006 0.006 0.020 0.048 0.003 0.000JCA-XRF-01 0.001 0.000 0.015 0.041 0.008 0.002 0.009 0.001JCA-XRF-02 0.045 0.009 0.011 0.059 0.003 0.015 0.008 0.001JCA-XRF-04 0.068 0.004 0.007 0.017 0.001 0.014 0.010 0.003JCA-XRF-05 0.047 0.003 0.012 0.029 0.011 0.010 0.009 0.000JCA-XRF-06 0.096 0.004 0.014 0.124 0.014 0.023 0.003 0.005JCA-XRF-07 0.003 0.013 0.003 0.121 0.010 0.002 0.002 0.004JCA-XRF-08 0.028 0.003 0.008 0.002 0.006 0.022 0.001 0.000JCA-XRF-09 0.005 0.002 0.008 0.085 0.004 0.002 0.006 0.005JCA-XRF-10 0.021 0.007 0.013 0.038 0.014 N/A 0.003 0.004JCA-XRF-11 0.039 0.025 0.015 0.061 0.009 N/A 0.006 0.005JCA-XRF-12 0.018 0.032 0.012 0.012 0.034 N/A 0.002 0.001JCA-XRF-13 0.031 0.006 0.010 0.049 0.025 N/A 0.001 0.003JCA-XRF-15 0.001 0.026 0.018 0.027 0.050 N/A 0.017 0.001

Abs. Max Er.a 0.096 0.060 0.050 0.124 0.050 0.057 0.029 0.005

ASTM Limit 0.2 0.2 0.10 0.3 0.2 0.1 0.05 0.05

Control SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2O K2O

Samplesb

(%) (%) (%) (%) (%) (%) (%) (%)

JCA-XRF-03 0.031 0.012 0.004 0.036 0.002 0.041 0.006 0.003JCA-XRF-14 0.006 0.046 0.014 0.006 0.018 N/A 0.001 0.002

a Abs. Max Er. = Absolute Maximum Errorb Results of control samples are include in the calculation for Abs. Max Er.


Table 10. ASTM C114: Accuracy Test Results (Part 2)

Calibrated TiO2 P2O5 Mn2O3 SrO Cr2O3 ZnO Sum

RM (%) (%) (%) (%) (%) (%) (%)

NIST 1880a 0.0169 0.0015 0.0013 0.0027 0.0015 0.0003 0.22NIST 1881a 0.0044 0.0056 0.0019 0.0008 0.0020 0.0013 0.10NIST 1884a 0.0015 0.0003 0.0061 0.0021 0.0001 0.0001 0.18NIST 1885a 0.0016 0.0015 0.0037 0.0016 0.0001 0.0007 0.09NIST 1886a 0.0023 0.0007 0.0065 0.0013 0.0008 0.0014 0.03NIST 1887a 0.0043 0.0016 0.0025 0.0033 0.0005 0.0026 0.16NIST 1888a 0.0047 0.0026 0.0006 0.0004 0.0007 0.0004 0.05NIST 1889a 0.0038 0.0024 0.0080 0.0012 0.0001 0.0011 0.08JCA-XRF-01 0.0007 0.0002 0.0086 0.0003 N/A N/A 0.06JCA-XRF-02 0.0058 0.0005 0.0000 0.0007 N/A N/A 0.11JCA-XRF-04 0.0077 0.0014 0.0003 0.0002 N/A N/A 0.04JCA-XRF-05 0.0068 0.0018 0.0103 0.0000 N/A N/A 0.05JCA-XRF-06 0.0007 0.0056 0.0045 0.0018 N/A N/A 0.17JCA-XRF-07 0.0006 0.0034 0.0020 0.0020 N/A N/A 0.29JCA-XRF-08 0.0054 0.0004 0.0046 0.0007 N/A N/A 0.01JCA-XRF-09 0.0005 0.0017 0.0055 0.0000 N/A N/A 0.26JCA-XRF-10 0.0035 0.0032 0.0084 0.0009 N/A N/A N/AJCA-XRF-11 0.0015 0.0102 0.0074 0.0003 N/A N/A N/AJCA-XRF-12 0.0141 0.0032 0.0016 0.0008 N/A N/A N/AJCA-XRF-13 0.0065 0.0012 0.0018 0.0021 N/A N/A N/AJCA-XRF-15 0.0019 0.0001 0.0181 0.0033 N/A N/A N/AAbs. Max Er.

a 0.0169 0.0102 0.0181 0.0033 0.0020 0.0026 0.29

ASTM Limit 0.03 0.03 0.03 --- --- 0.03 ---

Control TiO2 P2O5 Mn2O3 SrO Cr2O3 ZnO Sum

Samplesb

(%) (%) (%) (%) (%) (%) (%)

JCA-XRF-03 0.0040 0.0014 0.0016 0.0009 N/A N/A 0.09JCA-XRF-14 0.0095 0.0038 0.0036 0.0013 N/A N/A N/A

a Abs. Max Er. = Absolute Maximum Errorb Results of control samples are include in the calculation for Abs. Max Er.

-ISO Precision and accuracy

It is important to note that the ISO limits for precision and accuracy are not a fixed limitas in ASTM C 114. The ISO limits are pending the concentration of the element in thesamples analyzed. The ISO precision test was applied as described in the method [2].The absolute differences shown in tables 11, 12, 13 and 14 were calculated fromsuccessive results of the control samples. The maximum absolute difference for allelements is shown and compared to the ISO expert precision limit. The maximum valuesobtained for all elements meet the specified limits for both control samples.


Table 11. ISO: Precision Test Results of control sample JCA-XRF-03 (Part 1)

Precision SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2O K2O

(%) (%) (%) (%) (%) (%) (%) (%)

Difference 1 0.010 0.003 0.003 0.026 0.003 0.020 0.006 0.006Difference 2 0.010 0.018 0.017 0.066 0.004 0.001 0.005 0.002Difference 3 0.014 0.004 0.010 0.114 0.008 0.000 0.002 0.003Difference 4 0.004 0.030 0.003 0.003 0.000 0.002 0.000 0.006Difference 5 0.030 0.005 0.012 0.037 0.017 0.006 0.005 0.004Difference 6 0.017 0.017 0.003 0.027 0.023 0.013 0.003 0.001Difference 7 0.001 0.027 0.006 0.035 0.009 0.012 0.006 0.001Difference 8 0.000 0.024 0.000 0.059 0.008 0.015 0.008 0.006Difference 9 0.015 0.013 0.002 0.018 0.015 0.010 0.006 0.002Max Difference 0.030 0.030 0.017 0.114 0.023 0.020 0.008 0.006

ISO Expert Limit 0.134 0.062 0.054 0.235 0.044 0.054 0.023 0.023


Precision TiO2 P2O5 Mn2O3 SrO Cr2O3 ZnO Sum

(%) (%) (%) (%) (%) (%) (%)

Difference 1 0.0117 0.0075 0.0004 0.0004 0.0008 0.0005 0.06Difference 2 0.0073 0.0070 0.0008 0.0002 0.0016 0.0001 0.05Difference 3 0.0074 0.0065 0.0042 0.0024 0.0026 0.0018 0.11Difference 4 0.0049 0.0029 0.0011 0.0025 0.0023 0.0006 0.01Difference 5 0.0033 0.0029 0.0016 0.0005 0.0006 0.0002 0.01Difference 6 0.0127 0.0056 0.0020 0.0018 0.0001 0.0024 0.00Difference 7 0.0025 0.0047 0.0033 0.0003 0.0016 0.0031 0.05Difference 8 0.0142 0.0037 0.0037 0.0015 0.0022 0.0004 0.08Difference 9 0.0121 0.0068 0.0017 0.0018 0.0011 0.0029 0.01Max Difference 0.0142 0.0075 0.0042 0.0025 0.0026 0.0031 0.11

ISO Expert Limit 0.023 0.023 0.023 0.023 0.023 0.023 N/A


Precision SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2O K2O

(%) (%) (%) (%) (%) (%) (%) (%)

Difference 1 0.017 0.013 0.008 0.028 0.018 N/A 0.002 0.003Difference 2 0.011 0.006 0.002 0.006 0.017 N/A 0.008 0.003Difference 3 0.035 0.004 0.011 0.015 0.010 N/A 0.000 0.003Difference 4 0.052 0.006 0.008 0.067 0.011 N/A 0.005 0.001Difference 5 0.022 0.018 0.003 0.011 0.005 N/A 0.008 0.000Difference 6 0.019 0.020 0.011 0.093 0.010 N/A 0.003 0.002Difference 7 0.018 0.009 0.009 0.036 0.000 N/A 0.000 0.003Difference 8 0.018 0.010 0.004 0.036 0.011 N/A 0.001 0.002Difference 9 0.004 0.008 0.005 0.050 0.005 N/A 0.011 0.003Max Difference 0.052 0.020 0.011 0.093 0.018 N/A 0.011 0.003

ISO Expert Limit 0.149 0.081 0.054 0.217 0.054 N/A 0.023 0.023



Precision TiO2 P2O5 Mn2O3 SrO Cr2O3 ZnO Sum

(%) (%) (%) (%) (%) (%) (%)

Difference 1 0.0058 0.0028 0.0011 0.0016 0.0003 0.0014 0.10Difference 2 0.0009 0.0060 0.0018 0.0004 0.0003 0.0000 0.05Difference 3 0.0066 0.0026 0.0041 0.0026 0.0005 0.0015 0.01Difference 4 0.0014 0.0040 0.0021 0.0012 0.0033 0.0012 0.12Difference 5 0.0079 0.0068 0.0007 0.0000 0.0044 0.0001 0.02Difference 6 0.0107 0.0060 0.0034 0.0012 0.0058 0.0000 0.10Difference 7 0.0044 0.0059 0.0029 0.0016 0.0022 0.0004 0.09Difference 8 0.0016 0.0009 0.0014 0.0009 0.0013 0.0009 0.10Difference 9 0.0073 0.0048 0.0035 0.0008 0.0015 0.0014 0.07Max Difference 0.0107 0.0068 0.0041 0.0026 0.0058 0.0015 0.12

ISO Expert Limit 0.032 0.023 0.023 0.023 0.023 0.023 N/A

The ISO accuracy test was applied as described in the method [2]. The accuracy valuesshown in tables 15, 16, 17 and 18 were calculated as difference of the results from the 10preparations over 15 days against the certified values. The absolute maximum error forall elements is shown and compared to the ISO expert accuracy limit. The maximumvalues obtained for all elements are in the requirement limits for both control samples.

Table 15. ISO: Accuracy Test Results of control sample JCA-XRF-03 (Part 1)

Accuracy SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2O K2O

(%) (%) (%) (%) (%) (%) (%) (%)

Accuracy 1 0.027 0.014 0.006 0.049 0.004 0.052 0.003 0.006Accuracy 2 0.037 0.011 0.003 0.023 0.001 0.032 0.009 0.000Accuracy 3 0.047 0.007 0.020 0.089 0.005 0.033 0.014 0.002Accuracy 4 0.061 0.011 0.010 0.025 0.013 0.033 0.016 0.001Accuracy 5 0.057 0.019 0.007 0.022 0.013 0.035 0.016 0.007Accuracy 6 0.087 0.014 0.019 0.015 0.004 0.029 0.011 0.003Accuracy 7 0.070 0.003 0.022 0.012 0.019 0.016 0.008 0.004Accuracy 8 0.069 0.024 0.016 0.047 0.010 0.028 0.014 0.005Accuracy 9 0.069 0.000 0.016 0.012 0.002 0.013 0.009 0.001Accuracy 10 0.054 0.013 0.014 0.006 0.017 0.023 0.012 0.001Abs. Max Error 0.087 0.024 0.022 0.089 0.019 0.052 0.016 0.007

ISO Expert Limit 0.15 0.08 0.08 0.25 0.08 0.08 0.02 0.02



Accuracy TiO2 P2O5 Mn2O3 SrO Cr2O3 ZnO Sum

(%) (%) (%) (%) (%) (%) (%)

Accuracy 1 0.0099 0.0023 0.0014 0.0011 N/A N/A 0.12Accuracy 2 0.0018 0.0052 0.0018 0.0007 N/A N/A 0.06Accuracy 3 0.0055 0.0018 0.0010 0.0005 N/A N/A 0.11Accuracy 4 0.0019 0.0047 0.0052 0.0029 N/A N/A 0.00Accuracy 5 0.0030 0.0018 0.0041 0.0004 N/A N/A 0.01Accuracy 6 0.0003 0.0011 0.0025 0.0001 N/A N/A 0.02Accuracy 7 0.0124 0.0045 0.0045 0.0017 N/A N/A 0.02Accuracy 8 0.0099 0.0002 0.0012 0.0014 N/A N/A 0.07Accuracy 9 0.0043 0.0035 0.0049 0.0001 N/A N/A 0.01Accuracy 10 0.0078 0.0033 0.0032 0.0017 N/A N/A 0.00Abs. Max Error 0.0124 0.0052 0.0052 0.0029 N/A N/A 0.12

ISO Expert Limit 0.02 0.02 0.02 0.02 N/A N/A N/A


Accuracy SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2O K2O

(%) (%) (%) (%) (%) (%) (%) (%)

Accuracy 1 0.002 0.053 0.010 0.019 0.027 N/A 0.002 0.001Accuracy 2 0.015 0.040 0.018 0.009 0.009 N/A 0.000 0.004Accuracy 3 0.026 0.046 0.020 0.003 0.026 N/A 0.008 0.001Accuracy 4 0.009 0.042 0.031 0.018 0.016 N/A 0.008 0.004Accuracy 5 0.043 0.048 0.023 0.085 0.027 N/A 0.003 0.003Accuracy 6 0.021 0.066 0.026 0.096 0.022 N/A 0.011 0.003Accuracy 7 0.040 0.046 0.015 0.003 0.012 N/A 0.008 0.005Accuracy 8 0.058 0.055 0.024 0.039 0.012 N/A 0.008 0.002Accuracy 9 0.040 0.045 0.020 0.003 0.001 N/A 0.007 0.004Accuracy 10 0.036 0.037 0.015 0.053 0.006 N/A 0.004 0.001Abs. Max Error 0.058 0.066 0.031 0.096 0.027 N/A 0.011 0.005

ISO Expert Limit 0.15 0.12 0.08 0.25 0.08 N/A 0.02 0.02


Accuracy TiO2 P2O5 Mn2O3 SrO Cr2O3 ZnO Sum

(%) (%) (%) (%) (%) (%) (%)

Accuracy 1 0.0066 0.0024 0.0042 0.0005 N/A N/A N/AAccuracy 2 0.0124 0.0052 0.0031 0.0021 N/A N/A N/AAccuracy 3 0.0133 0.0008 0.0013 0.0025 N/A N/A N/AAccuracy 4 0.0067 0.0018 0.0028 0.0001 N/A N/A N/AAccuracy 5 0.0053 0.0058 0.0007 0.0011 N/A N/A N/AAccuracy 6 0.0026 0.0010 0.0014 0.0011 N/A N/A N/AAccuracy 7 0.0081 0.0050 0.0020 0.0023 N/A N/A N/AAccuracy 8 0.0037 0.0009 0.0009 0.0007 N/A N/A N/AAccuracy 9 0.0053 0.0018 0.0023 0.0016 N/A N/A N/AAccuracy 10 0.0020 0.0030 0.0012 0.0008 N/A N/A N/AAbs. Max Error 0.0133 0.0058 0.0042 0.0025 N/A N/A N/A

ISO Expert Limit 0.03 0.02 0.02 0.02 N/A N/A N/A


-Qualification of Reference Material not included in the calibration

The last step of the project was to use one set of RM's for the calibration and then adifferent set of RM�� Qualification.The same glass disks used for the calibration with both RM series were used toinvestigate this point. It is not interesting to discuss the precision for this part of theexperiment, because no parameters were changed in the fusion process and in the XRFanalysis. Only calibration parameters have been changed, so only accuracy results willchange. The first test was to create a calibration including only NIST SRM��, thenanalyze JCA RM�� as unknowns and look for ASTM accuracy test results. The resultsare available in table 19. All absolute maximum errors are within the specified limitexcept for SiO2 and Mn2O3 which only one result out of fifteen is out for both elements.Those results of SiO2 and Mn2O3 for RM JCA-XRF-15 are out of the limits but it is lessthan the double of the limits. ASTM standard method specifies that when you use morethan seven RM's, at least 77% shall be within the prescribed limits, and the remainder byno more than twice the value [1]. JCA RM's therefore were qualified by ASTM methodeven though they were not included in the calibration.

Table 19. ASTM C114: Accuracy Test Results for qualification of JCA using acalibration including only NIST SRM's

Reference SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2O K2O TiO2 P2O5 Mn2O3 SrO

Materials (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%)

JCA-XRF-01 0.078 0.009 0.009 0.040 0.021 0.020 0.016 0.001 0.0072 0.0000 0.0083 0.0012JCA-XRF-02 0.092 0.017 0.006 0.060 0.014 0.043 0.016 0.001 0.0126 0.0007 0.0039 0.0015JCA-XRF-03 0.060 0.008 0.000 0.048 0.015 0.049 0.013 0.002 0.0112 0.0027 0.0051 0.0017JCA-XRF-04 0.097 0.003 0.004 0.020 0.012 0.022 0.017 0.004 0.0136 0.0071 0.0054 0.0011JCA-XRF-05 0.071 0.013 0.007 0.034 0.024 0.013 0.016 0.001 0.0119 0.0009 0.0026 0.0007JCA-XRF-06 0.124 0.010 0.011 0.119 0.026 0.033 0.004 0.005 0.0055 0.0054 0.0019 0.0026JCA-XRF-07 0.090 0.012 0.009 0.113 0.023 0.022 0.005 0.003 0.0029 0.0030 0.0025 0.0028JCA-XRF-08 0.134 0.003 0.002 0.013 0.017 0.054 0.008 0.000 0.0010 0.0035 0.0009 0.0015JCA-XRF-09 0.130 0.006 0.015 0.077 0.017 0.033 0.000 0.005 0.0003 0.0020 0.0039 0.0009JCA-XRF-10 0.120 0.026 0.010 0.029 0.029 N/A 0.010 0.004 0.0059 0.0052 0.0086 0.0001JCA-XRF-11 0.180 0.059 0.011 0.079 0.027 N/A 0.013 0.006 0.0053 0.0151 0.0065 0.0005JCA-XRF-12 0.181 0.087 0.008 0.031 0.059 N/A 0.005 0.000 0.0073 0.0014 0.0042 0.0016JCA-XRF-13 0.176 0.061 0.006 0.027 0.047 N/A 0.007 0.002 0.0126 0.0001 0.0258 0.0012JCA-XRF-14 0.188 0.087 0.009 0.012 0.043 N/A 0.008 0.001 0.0162 0.0033 0.0045 0.0005JCA-XRF-15 0.289 0.091 0.013 0.052 0.093 N/A 0.024 0.002 0.0263 0.0016 0.0392 0.0025Abs. Max Er.

a0.289 0.091 0.030 0.119 0.093 0.054 0.024 0.006 0.0263 0.0151 0.0392 0.0032

ASTM Limit 0.2 0.2 0.10 0.3 0.2 0.1 0.05 0.05 0.03 0.03 0.03 ---

a: Abs. Max Er. = Absolute Maximum Error

The second test was to create a calibration including only JCA RM's, and then analyzeNIST SRM's as unknowns, looking to meet ASTM C 114 accuracy specifications. Theresults are available in table 20. All absolute maximum errors are within the specifiedlimit except for Na2O where only one result out of eight is out. This result of Na2O forRM NIST 1885a is out of the limit but it is less than the double of the limit. As for theprevious test, these results meet the ASTM requirements for the same reason. NISTSRM's were qualified by ASTM method even though they were not included in thecalibration.


Table 20. ASTM C114: Accuracy Test Results for qualification of NIST using acalibration including only JCA

Reference SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2O K2O TiO2 P2O5 Mn2O3 SrO

Materials (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%)

NIST 1880a 0.009 0.060 0.018 0.067 0.013 0.087 0.006 0.003 0.0185 0.0008 0.0013 0.0015NIST 1881a 0.007 0.045 0.005 0.035 0.055 0.044 0.004 0.008 0.0053 0.0043 0.0047 0.0014NIST 1884a 0.005 0.010 0.050 0.112 0.048 0.025 0.006 0.005 0.0036 0.0009 0.0091 0.0270NIST 1885a 0.003 0.013 0.019 0.076 0.043 0.016 0.077 0.005 0.0036 0.0003 0.0070 0.0599NIST 1886a 0.035 0.016 0.006 0.144 0.022 0.020 0.006 0.001 0.0004 0.0007 0.0103 0.0037NIST 1887a 0.044 0.027 0.003 0.032 0.043 0.121 0.029 0.006 0.0057 0.0017 0.0051 0.0244NIST 1888a 0.021 0.042 0.025 0.050 0.043 0.067 0.024 0.001 0.0031 0.0019 0.0020 0.0034NIST 1889a 0.018 0.067 0.007 0.023 0.022 0.031 0.003 0.000 0.0020 0.0015 0.0068 0.0012Abs. Max Er.

a0.044 0.067 0.050 0.144 0.055 0.121 0.077 0.008 0.0185 0.0043 0.0103 0.0599

ASTM Limit 0.2 0.2 0.10 0.3 0.2 0.1 0.05 0.05 0.03 0.03 0.03 ---

a: Abs. Max Er. = Absolute Maximum Error

It is interesting to note that NIST 1885a Na2O value is 1.086% on an LOI free basis. Ifwe compare it to the JCA series Na2O calibration range in the table 4, it is far beyond themaximum value covered by the JCA series. The same situation occurs for the JCA-XRF-15, SiO2 (29.29%) and Mn2O3 (0.53%) values, which are beyond the range covered bythe NIST SRM series for SiO2 and Mn2O3.

CONCLUSIONS

A global fusion/XRF analytical method for cement industry materials has been describedin this paper. This method of preparation by fusion allows fusing cements and all the rawmaterials normally found in a cement plant. The overall method complies with theprecision and accuracy requirements of the international standard methods for cementanalysis (ISO/DIS 29581-2 and ASTM C 114). Moreover, qualification by ASTM C 114of both complete series of reference materials (NIST SRM's and JCA RM's) not includedin the calibration was achieved, which is a step forward in quality control for chemicalanalysis in the cement industry.

Acknowledgements

The authors thank Luc B"�� "��#��$�� support in the project. Finally, the authors have special thanks for M"��%�� Corporation Scientifique Claisse for her devoted work in the laboratory. She fused morethan a 1,000 beads for this project.


References

1. ASTM, Standard C114 - 08, �#�� &�� '��s for Chemical Analysis of HydraulicCement(�� Annual Book of ASTM Standards, Volume 04.01, ASTM International, WestConshohocken, PA, 2008, pp. 150�157.2. DIN EN ISO 29581-2 (Draft standard, 2007-07), Methods of testing cement - Chemicalanalysis of cement - Part 2: Analysis by X-ray fluorescence (ISO/DIS 29581-2:2007), 30 pp.3. Anzelmo, J.A., "The Role of XRF, Inter-Element Corrections, and SamplePreparation Effects in the 100-Year Evolution of ASTM Standard Test Method C114", Journal ofASTM International, Vol. 6, No. 2, Paper ID JAI101730, available online at www.astm.org, 2009,pp 1-10.4. Spangenberg, J. and Fontbot"��) , "X-Ray Fluorescence Analysis of Base Metal Sulphide andIron-Manganese Oxide Ore Samples in Fused Glass Disc", X-Ray Spectrometry, Vol. 23, 1994,pp 83-90.5. Loubser, M., Strydom, C., and Potgieter, H., "A Thermogravimetric Analysis Study ofVolatilization of Flux Mixtures Used in XRF Sample Preparation", X-Ray Spectrom. 2004; 33:212�215, Published online 29 January 2004 in Wiley InterScience(www.interscience.wiley.com). DOI: 10.1002/xrs.7006. Berube L., Rivard S., Anzelmo J., "XRF Fusion Precision with TheAnt", International CementReview, March, 2008, 4 pp.


cement by xrf

Documents