ASTM C1271-99(2020)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: C1271 − 99 (Reapproved 2020)
Standard Test Method for
X-ray Spectrometric Analysis of Lime and Limestone
This standard is issued under the fixed designation C1271; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope Emission Spectrochemical Analytical Curves
E456 Terminology Relating to Quality and Statistics
1.1 This test method covers the X-ray emission spectromet-
E691 Practice for Conducting an Interlaboratory Study to
ric analysis of limestone, quicklime, hydrated lime, and hy-
Determine the Precision of a Test Method
draulic lime using wavelength dispersive instruments.
E1060 Practice for Interlaboratory Testing of Spectrochemi-
1.2 The values stated in SI units are to be regarded as the
cal Methods of Analysis (Withdrawn 1997)
standard.
E1361 Guide for Correction of Interelement Effects in
1.3 This standard does not purport to address all of the X-Ray Spectrometric Analysis
safety concerns, if any, associated with its use. It is the
2.2 NIST Documents:
responsibility of the user of this standard to establish appro- ANSI-NIST Handbook 114
priate safety, health, and environmental practices and deter-
NIST Standards Catalog
mine the applicability of regulatory limitations prior to use.
3. Terminology
Specific precautionary statements are given in Section 10.
1.4 This international standard was developed in accor-
3.1 Definitions:
dance with internationally recognized principles on standard-
3.1.1 emission spectroscopy—unless otherwise specified,
ization established in the Decision on Principles for the
for definitions of terms used in this test method pertaining to
Development of International Standards, Guides and Recom-
emission spectroscopy, refer to Terminology E135.
mendations issued by the World Trade Organization Technical
3.1.2 lime—unless otherwise specified, for definitions of
Barriers to Trade (TBT) Committee.
terms used in this test method pertaining to lime, refer to
Terminology C51.
2. Referenced Documents
3.1.3 statistical—unless otherwise specified, for definitions
2.1 ASTM Standards:
of terms used in this test method pertaining to statistics, refer
C25 Test Methods for Chemical Analysis of Limestone,
to Terminology E456.
Quicklime, and Hydrated Lime
C50 Practice for Sampling, Sample Preparation, Packaging, 4. Summary of Test Method
and Marking of Lime and Limestone Products
4.1 A briquetted powder specimen or a fused-glass disk
C51 Terminology Relating to Lime and Limestone (as Used
specimen is irradiated by a high-energy X-ray beam. The
by the Industry)
secondary X rays produced are dispersed by means of crystals,
E50 Practices for Apparatus, Reagents, and Safety Consid-
and the intensities are measured by suitable detectors at
erations for Chemical Analysis of Metals, Ores, and
selected wavelengths. Data are collected based on the time
Related Materials
required to reach a fixed number of counts, total count for a
E135 Terminology Relating to Analytical Chemistry for
fixed time, or integration of voltage for a fixed time. Concen-
Metals, Ores, and Related Materials
trations of the elements are determined by relating the mea-
E305 Practice for Establishing and Controlling Atomic
sured radiation of unknown specimens to analytical curves
prepared from reference materials of known composition.
This test method is under the jurisdiction of ASTM Committee C07 on Lime
5. Significance and Use
andLimestoneandisthedirectresponsibilityofSubcommitteeC07.05onChemical
5.1 Thisprocedureissuitableformanufacturingcontroland
Tests.
Current edition approved Dec. 1, 2020. Published January 2021. Originally
verifying that the product meets specifications. It provides
approved in 1994. Last previous edition approved in 2012 as C1271 – 99 (2012).
DOI: 10.1520/C1271-99R20.
2 3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or The last approved version of this historical standard is referenced on
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM www.astm.org.
Standards volume information, refer to the standard’s Document Summary page on Available from National Institute of Standards and Technology (NIST), 100
the ASTM website. Bureau Dr., Stop 1070, Gaithersburg, MD 20899-1070, http://www.nist.gov.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1271 − 99 (2020)
rapid, multi-element determinations with sufficient accuracy to be aware at all times of possible contamination from the
ensure product quality and minimize production delays. The polishing media used for surfacing the disk (6.3).
analytical performance data included may be used as a bench-
7.4 Excitation Source:
mark to determine whether similar X-ray spectrometers pro-
7.4.1 X-Ray Tube Power Supply, providing constant poten-
vide equivalent precision and accuracy, or whether the perfor-
tialorrectifiedpowerofsufficientenergytoproducesecondary
mance of a particular X-ray spectrometer has changed.
radiation of the specimen for the elements specified. The
generator may be equipped with a line voltage regulator and
6. Interferences
current stabilizer.
6.1 Interelementeffectsormatrixeffectsmayexistforsome
7.4.2 X-Ray Tubes, with targets of various high-purity
of the elements listed. One way to compensate for these effects
elements, capable of continuous operation at required poten-
is to prepare a series of calibration curves to cover the
tials and currents, and that will excite the elements to be
designated concentration ranges.The composition of the speci-
determined.
men being analyzed must match closely the composition of the
7.5 Spectrometer, designed for X-ray emission analysis and
reference materials used to prepare the calibration curve.
equipped with specimen holders and a specimen chamber. The
Mathematicalcorrections,derivedfromempiricalrelationships
chamber may contain a specimen spinner, and it must be
or fundamental parameter calculations, may be used alterna-
equipped for vacuum operation.
tively.Anyoftheseareacceptable,providingthattheanalytical
7.5.1 Analyzing Crystals—Flat or curved crystals with op-
accuracy required by this test method is achieved.
timizedcapabilityfordiffractionofthewavelengthsofinterest.
6.2 Calcium is the primary component of the matrix ana-
7.5.2 Collimator, for limiting the characteristic X rays to a
lyzed by this test method. The analyst must be aware of all
parallel bundle when flat crystals are used in the instrument.A
possible interferences and matrix effects of this element.
collimator is not necessary for curved crystal optics.
Ordersofallwavelengthsmaycauseinterference,forexample,
7.5.3 Detectors, sealed or gas flow, proportional type, Gei-
the effect of CaKβ1 (2nd order) on PKα1.
ger counters, scintillation counters or equivalent.
7.5.4 Vacuum System, providing for the determination of
6.3 Contamination from the grinding apparatus is an ever-
presentsourceofinterferenceofwhichtheanalystmustalways elements whose radiation is absorbed by air (atomic number
below 20). The system shall consist of at least one vacuum
be cognizant. For example, stainless steel will impart iron,
pump, gage, and electrical controls to provide automatic
chrome, and nickel to the prepared sample.
pumpdown of the optical path and maintain a controlled
6.4 Spectral interferences from the X-ray tube may also
pressure, usually 13 Pa or less.
occur, for example, line overlap from CrKβ1onMnKα1
7.6 Measuring System, consisting of electronic circuits ca-
caused by a chrome target tube.
pable of counting or integrating pulses received from the
7. Apparatus
detectors.Thecounts,countrate,orintegratedvoltagesmaybe
displayed on meters, recorders, digital counters, or voltmeters.
7.1 Specimen Preparation Equipment:
The counts, count rates, or integrated voltages can also be
7.1.1 Jaw Crusher, for initial crushing of lumps.
presented to a computer or programmable calculator for
7.1.2 Plate Grinder or Pulverizer, with one static and one
conversion to percent concentration. Pulse height analyzers
rotating disk for further grinding.
may be required to provide more accurate measurements for
7.1.3 Rotary Disk Mill or Shatter Box, with hardened
some measurements.
grinding containers and timer control for final grinding.
7.2 Briquetting Equipment: 8. Reagents and Materials
7.2.1 Briquetting Press, capable of providing pressures up
8.1 Purity and Concentration of Reagents—The purity and
to 550 MPa (80 000 psi). The press shall be equipped with a
concentration of chemical reagents shall conform to the re-
mold assembly that provides a briquet compatible with the
quirements prescribed in Practices E50.
X-ray specimen holder.
8.2 Binders—Various binders have been used successfully
7.3 Fusion Equipment:
topreparebriquettessuitableforpresentationtotheinstrument.
7.3.1 Furnace or Gas Burners, with a timer, capable of
Asageneralrule,thebindershouldnotcontainanelementthat
heating the sample and flux to at least 1000 °C and homog-
will be determined. In addition, the sample to binder ratio must
enizing the melt.
be present in the analytical sample as in the reference materials
7.3.2 Fusion Crucibles:
that were used to establish the calibration.
7.3.2.1 Vitreous Carbon or Graphite, 20 to 30 mL capacity,
8.3 Fluxes—Various fluxes have been used successfully to
with a flat bottom 30 to 35 mm in diameter.
prepare fusion disks.The flux must be capable of dissolving or
7.3.2.2 Platinum/Gold, 95 % platinum/5 % gold alloy, 30 to
dispersing the analyzed elements in an homogeneous and
35 mL capacity.
reproducible fashion in the melt. The prepared disks must then
7.3.2.3 Platinum/Gold Casting Dish, 95 % platinum/5 %
be suitable for presentation to the instrument.
gold alloy, 30 to 35 mL capacity, with a flat bottom 30 to 35
mm in diameter. 8.4 Detector Gas (P-10), consisting of a mixture of 90 %
7.3.3 Polishing Wheel, suitable for polishing the fusion disk argon and 10 % methane for use with gas flow proportional
to obtain a uniform surface for irradiation. The analyst should counters only.
C1271 − 99 (2020)
9. Reference Materials 13. Preparation of Apparatus
9.1 Certified reference materials are available from the 13.1 Prepare and operate the spectrometer in accordance
National Institute for Standards and Technology (NIST) and with the manufacturer’s instructions, using the parameters
other international certification agencies. Refer to Test Meth- given in Table 1. Once established, control all instrument
ods C25 for a current listing. parameters closely to ensure repeatable analyses.
9.2 Reference materials with matrixes similar to that of the
14. Calibration and Standardization
test specimen and containing varying amounts of the elements
14.1 Calibration (Preparation of Analytical Curves)—
to be determined may be used provided that they have been
Select a sufficient number of reference materials to cover the
analyzed in accordance with ASTM standard test methods.
concentration ranges of the elements sought.Average duplicate
9.3 Standard additions method or spiked samples may also
intensity measurements of each reference material, and estab-
be used to create standards for which appropriate reference
lish a calibration curve for each element in accordance with
materials are not available for an element desired to be
Practice E305. Establish the curve by a least squares or
analyzed. The matrix material must match that of the test
multiple regression fit of the X-ray intensity measurements
specimen.
versus the corresponding weight percent concentrations of the
element in the reference materials.
10. Safety Precautions
14.2 Standardization (Analytical Curve Adjustment)—
10.1 Occupational health and safety standards for ionizing
Verify that the calibration curve for each element has not
radiation shall be observed at all X-ray emission spectrometer
drifted using a control reference material. Drift is indicated by
installations. It is also recommended that operating and main-
a change in counts that exceeds the normal variation of counts
tenance personnel follow the guidelines of safe operating
for that element. A change of 1 % or greater usually signifies
procedures given in current handbooks and publications from
that the calibration curve for that element has drifted and
the original equipment manufacturer, NIST, U.S. Government
should thus be adjusted. Re-measure the reference materials to
Printing Office, or similar handbooks on radiation safety. See
verify that acceptable analyses are obtained after the adjust-
NIST Standards Catalog and ANSI-NIST Handbook 114.
ments are made.
10.2 Personnel—X-ray equipment shall be used only under
15. Procedure
theguidanceandsupervisionofaresponsible,qualifiedperson.
15.1 Excitation—Introduce the specimen into the specimen
10.3 Monitoring Devices—Either film badges or dosimeters
chamber, using care not to contaminate the surface to be
shall be worn by all operating and maintenance personnel.
excited. Produce the secondary fluorescence using the equip-
Periodic radiation surveys of the equipment for leaks and
ment used in 7.4.
excessive scattered radiation shall be made by a qualified
person using an ionization chamber detector to meet local,
15.2 Radiation Measurements—Obtain and record the
state, and federal radiation standards. The personal film badge
countingratemeasurementforeachelement.Eitherfixedcount
survey record, the radiation survey record, and an equipment
or fixed time modes may be used. A predetermined minimum
maintenance record shall be available upon request.
count rate is obtainable only after unacceptable long counting
timesforlimematerials,withtheexceptionofthemajoroxides
10.4 Special precautions for operators and maintenance
(Si, Fe, Al, Ca, and Mg). A minimum counting time of 60 s is
personnel shall be posted at the equipment site.
acceptable.
10.5 Radiation caution signs shall be posted near the X-ray
15.3 Spectral Interferences—Some X-ray spectrometers
equipment and at all entrances to the radiation area.
will not resolve radiation completely from several line over-
10.6 Fail-Safe “X-ray on” warning lights shall be used on
laps. Care must therefore be exercised in these cases.Alternate
the equipment.
11. Sampling
TABLE 1 Analytical Lines and Crystals
Element Wavelength, A Crystals
11.1 Gross sample is to be taken in accordance wit
...