ASTM C1463-19

Standard Practices for Dissolving Glass Containing Radioactive and Mixed Waste for Chemical and Radiochemical Analysis

ABSTRACT
These practices cover three standard technique for dissolving glass samples containing radioactive, nuclear, and mixed wastes. These techniques used together or independently will produce solutions that can be analyzed by inductively coupled plasma atomic emission spectroscopy (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS), atomic absorption spectrometry (AAS), radiochemical methods and wet chemical techniques for major components, minor components and radionuclides. The practices for dissolving silicate matrix samples each require the sample to be initially dried and ground to a fine powder. The first practice involves the mixing and fusion of the sample with sodium tetraborate (Na2B4O7) and sodium carbonate (Na2CO4) in a muffle for a given amount of time and temperature. The sample is then cooled, dissolved in hydrochloric acid, and diluted to appropriate volume for analyses. The second practice, on the other hand, involves the fusion of the sample with potassium hydroxide (KOH) or sodium peroxide (Na2O2) using an electric bunsen burner, dissolving the fused sample in water and dilute HCl, and making to volume for analyses. Finally, the third practice involves the dissolution of the sample using a microwave oven. The ground sample is digested in a microwave oven using a mixture of hydrofluoric (HF) and nitric (HNO3) acids. Boric acid is added to the resulting solution to complex excess fluoride ions.
SCOPE
1.1 These practices cover techniques suitable for dissolving glass samples that may contain nuclear wastes. These techniques used together or independently will produce solutions that can be analyzed by inductively coupled plasma atomic emission spectroscopy (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS), atomic absorption spectrometry (AAS), radiochemical methods and wet chemical techniques for major components, minor components and radionuclides.  
1.2 One of the fusion practices and the microwave practice can be used in hot cells and shielded hoods after modification to meet local operational requirements.  
1.3 The user of these practices must follow radiation protection guidelines in place for their specific laboratories.  
1.4 Additional information relating to safety is included in the text.  
1.5 The dissolution techniques described in these practices can be used for quality control of the feed materials and the product of plants vitrifying nuclear waste materials in glass.  
1.6 These practices are introduced to provide the user with an alternative means to Test Methods C169 for dissolution of waste containing glass in shielded facilities. Test Methods C169 is not practical for use in such facilities and with radioactive materials.  
1.7 The ICP-AES methods in Test Methods C1109 and C1111 can be used to analyze the dissolved sample with additional sample preparation as necessary and with matrix effect considerations. Additional information as to other analytical methods can be found in Test Method C169.  
1.8 Solutions from this practice may be suitable for analysis using ICP-MS after establishing laboratory performance criteria and verification that the criteria can be met. For example, Test Methods C1287 or C1637 may be used with additional sample preparation as necessary and appropriate matrix effect considerations.  
1.9 The values stated in SI units are to be regarded as standard. Units in parentheses are for information only.  
1.10 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Sections 10, 20, and 30.  
1.11 This international standard was developed in accordance with internationally recognized principles on standardization established in the De...

General Information

• Status: Published
• Publication Date: 31-Jan-2019
• ICS: 13.030.30 - Special wastes
• Technical Committee: C26 - Nuclear Fuel Cycle
• Drafting Committee: C26.05 - Methods of Test

Relations

• Replaces: ASTM C1463-13 - Standard Practices for Dissolving Glass Containing Radioactive and Mixed Waste for Chemical and Radiochemical Analysis
• Effective Date: 01-Feb-2019
• Refers: ASTM C859-24 - Standard Terminology Relating to Nuclear Materials
• Effective Date: 01-Jan-2024
• Refers: ASTM C1109-23 - Standard Practice for Analysis of Aqueous Leachates from Nuclear Waste Materials Using Inductively Coupled Plasma-Atomic Emission Spectroscopy
• Effective Date: 01-Dec-2023
• Refers: ASTM C1287-18 - Standard Test Method for Determination of Impurities in Nuclear Grade Uranium Compounds by Inductively Coupled Plasma Mass Spectrometry
• Effective Date: 01-Jan-2018
• Refers: ASTM C1109-10(2015) - Standard Practice for Analysis of Aqueous Leachates from Nuclear Waste Materials Using Inductively Coupled Plasma-Atomic Emission Spectroscopy
• Effective Date: 01-Jun-2015
• Refers: ASTM C859-14a - Standard Terminology Relating to Nuclear Materials
• Effective Date: 15-Jun-2014
• Refers: ASTM C859-14 - Standard Terminology Relating to Nuclear Materials
• Effective Date: 15-Jan-2014
• Refers: ASTM E11-13 - Standard Specification for Woven Wire Test Sieve Cloth and Test Sieves
• Effective Date: 01-Oct-2013
• Refers: ASTM C859-13a - Standard Terminology Relating to Nuclear Materials
• Effective Date: 01-Jun-2013
• Refers: ASTM C859-13 - Standard Terminology Relating to Nuclear Materials
• Effective Date: 01-May-2013
• Refers: ASTM C169-92(2011) - Standard Test Methods for Chemical Analysis of Soda-Lime and Borosilicate Glass
• Effective Date: 01-Oct-2011
• Refers: ASTM C859-10b - Standard Terminology Relating to Nuclear Materials
• Effective Date: 01-Nov-2010
• Refers: ASTM C1109-10 - Standard Practice for Analysis of Aqueous Leachates from Nuclear Waste Materials Using Inductively Coupled Plasma-Atomic Emission Spectrometry
• Effective Date: 01-Oct-2010
• Refers: ASTM C859-10a - Standard Terminology Relating to Nuclear Materials
• Effective Date: 01-Aug-2010
• Refers: ASTM C1287-10 - Standard Test Method for Determination of Impurities in Nuclear Grade Uranium Compounds by Inductively Coupled Plasma Mass Spectrometry
• Effective Date: 01-Jun-2010

Overview

ASTM C1463-19 is a widely recognized standard developed by ASTM International. It sets forth standardized practices for dissolving glass materials that may contain radioactive or mixed waste, enabling precise chemical and radiochemical analysis. These methods are essential for laboratories and facilities dealing with nuclear waste management, glass vitrification processes, and regulatory compliance.

This standard details three core dissolution techniques tailored for various analytical applications, including Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES), Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Atomic Absorption Spectrometry (AAS), and other radiochemical and wet chemical methodologies. The procedures are designed to ensure laboratory safety, robust contamination control, and accurate assessment of both major and trace components present in glass samples.

Key Topics

• Sample Preparation: Covers preparation steps such as drying and grinding radioactive glass samples to a fine powder for effective dissolution.
• Dissolution Practices:
  • Fusion with Sodium Tetraborate and Sodium Carbonate: Ideal for determining major oxides. Involves fusion in a muffle furnace and subsequent acid dissolution.
  • Fusion with Potassium Hydroxide or Sodium Peroxide: Suitable for difficult-to-dissolve matrices, employing an electric Bunsen burner and specialized crucibles for shielded facility use.
  • Microwave Digestion: Uses hydrofluoric and nitric acids for rapid dissolution and is effective for vitrified plant samples. Boric acid is used to complex fluoride ions.
• Safety and Containment: Emphasizes the need for radiation protection guidelines, use of shielded hoods or hot cells, and careful handling of hazardous reagents such as hydrofluoric acid.
• Analytical Compatibility: Ensures the resulting solutions are appropriate for a wide range of analytical techniques (ICP-AES, ICP-MS, AAS, and radiochemical analysis).

Applications

ASTM C1463-19 is crucial for:

• Nuclear Waste Management: Provides robust methods for dissolving glass matrices containing radioactive or mixed waste, enabling accurate determination of radionuclides and contaminants.
• Glass Vitrification Plants: Supports quality control and compliance by enabling chemical analysis of vitrified waste products and feed materials.
• Regulatory and Environmental Monitoring: Facilitates trace and bulk analysis of hazardous constituents to meet governmental and environmental standards.
• Shielded Facility Operations: Methods are adaptable for use in hot cells and shielded hoods, ensuring operator safety when working with high activity materials.
• Alternative Analytical Approaches: Offers practical alternatives to methods like ASTM C169, particularly where conventional procedures are not feasible for radioactive or shielded environments.

Related Standards

Several other ASTM standards and test methods complement or reference ASTM C1463-19, including:

• ASTM C169: Methods for chemical analysis of soda-lime and borosilicate glass.
• ASTM C859: Terminology relating to nuclear materials.
• ASTM C1109, C1111: ICP-AES analysis methods for aqueous leachates and waste streams.
• ASTM C1220: Static leaching of monolithic waste forms for radioactive waste disposal.
• ASTM C1285: Chemical durability testing of nuclear and hazardous waste glasses.
• ASTM C1287, C1637: ICP-MS methods for impurity determination in nuclear-grade materials.
• ASTM D1193: Specification for reagent water used in laboratory analysis.
• ASTM E11: Specification for woven wire test sieve cloth and sieves.

Conclusion

ASTM C1463-19 is a foundational resource for laboratories and facilities involved in the management, processing, and analysis of glass containing radioactive and mixed waste. By providing standardized, safe, and effective dissolution methods, it enhances analytical accuracy, operational safety, and regulatory compliance in the demanding field of nuclear waste management. For comprehensive chemical and radiochemical analysis of waste glass, adherence to ASTM C1463-19 ensures high-quality, defensible results across a range of critical applications.

Standards Content (Sample)

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: C1463 − 19
Standard Practices for
Dissolving Glass Containing Radioactive and Mixed Waste
for Chemical and Radiochemical Analysis
This standard is issued under the fixed designation C1463; 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 Test Methods C1287 or C1637 may be used with additional
sample preparation as necessary and appropriate matrix effect
1.1 These practices cover techniques suitable for dissolving
considerations.
glass samples that may contain nuclear wastes. These tech-
1.9 The values stated in SI units are to be regarded as
niques used together or independently will produce solutions
standard. Units in parentheses are for information only.
that can be analyzed by inductively coupled plasma atomic
emission spectroscopy (ICP-AES), inductively coupled plasma
1.10 This standard does not purport to address all of the
mass spectrometry (ICP-MS), atomic absorption spectrometry
safety concerns, if any, associated with its use. It is the
(AAS), radiochemical methods and wet chemical techniques
responsibility of the user of this standard to establish appro-
for major components, minor components and radionuclides.
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
1.2 One of the fusion practices and the microwave practice
Specific precautionary statements are given in Sections 10, 20,
can be used in hot cells and shielded hoods after modification
and 30.
to meet local operational requirements.
1.11 This international standard was developed in accor-
1.3 The user of these practices must follow radiation pro-
dance with internationally recognized principles on standard-
tection guidelines in place for their specific laboratories.
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
1.4 Additional information relating to safety is included in
mendations issued by the World Trade Organization Technical
the text.
Barriers to Trade (TBT) Committee.
1.5 The dissolution techniques described in these practices
can be used for quality control of the feed materials and the
2. Referenced Documents
product of plants vitrifying nuclear waste materials in glass.
2.1 ASTM Standards:
1.6 These practices are introduced to provide the user with
C169 Test Methods for Chemical Analysis of Soda-Lime
an alternative means to Test Methods C169 for dissolution of
and Borosilicate Glass
waste containing glass in shielded facilities. Test Methods
C859 Terminology Relating to Nuclear Materials
C169 is not practical for use in such facilities and with C1109 Practice for Analysis of Aqueous Leachates from
radioactive materials.
Nuclear Waste Materials Using Inductively Coupled
Plasma-Atomic Emission Spectroscopy
1.7 The ICP-AES methods in Test Methods C1109 and
C1111 Test Method for Determining Elements in Waste
C1111 can be used to analyze the dissolved sample with
StreamsbyInductivelyCoupledPlasma-AtomicEmission
additional sample preparation as necessary and with matrix
Spectroscopy
effect considerations. Additional information as to other ana-
C1220 Test Method for Static Leaching of MonolithicWaste
lytical methods can be found in Test Method C169.
Forms for Disposal of Radioactive Waste
1.8 Solutions from this practice may be suitable for analysis
C1285 Test Methods for Determining Chemical Durability
using ICP-MS after establishing laboratory performance crite-
of Nuclear, Hazardous, and Mixed Waste Glasses and
ria and verification that the criteria can be met. For example,
MultiphaseGlassCeramics:TheProductConsistencyTest
(PCT)
C1287 Test Method for Determination of Impurities in
These practices are under the jurisdiction ofASTM Committee C26 on Nuclear
Fuel Cycle and are the direct responsibility of Subcommittee C26.05 on Methods of
Test. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Feb. 1, 2019. Published February 2019. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 2000. Last previous edition approved in 2013 as C1463 – 13. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/C1463-19. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1463 − 19
Nuclear Grade Uranium Compounds by Inductively oxides in glasses, ceramics, and raw materials. The solutions
Coupled Plasma Mass Spectrometry are analyzed by atomic spectroscopy methods. Analyte con-
C1637 Test Method for the Determination of Impurities in centrations ranging from trace to major levels can be measured
PlutoniumMetal:AcidDigestionandInductivelyCoupled in these solutions, depending on the sample weights and
Plasma-Mass Spectroscopy (ICP-MS) Analysis dilution volumes used during preparation.
D1193 Specification for Reagent Water
7. Technical Precautions
E11 Specification for Woven Wire Test Sieve Cloth and Test
Sieves 7.1 This procedure is not useful for the determination of
boron or sodium since these elements are contained in the flux
3. Terminology
material.
3.1 For definitions of terms used in this Practice, refer to
7.2 The user is cautioned that with analysis by ICP-AES,
Terminology C859.
AAS, and ICP-MS, the high sodium concentrations from the
flux may cause interferences.
4. Summary of Practice
7.3 Elements that form volatile species under these alkaline
4.1 The three practices for dissolving silicate matrix
fusionconditionsmaybelostduringthefusionprocess(thatis,
samples each require the sample to be dried and ground to a
As and Sb).
fine powder.
8. Apparatus
4.2 In the first practice, a mixture of sodium tetraborate
(Na B O ) and sodium carbonate (Na CO ) is mixed with the
2 4 7 2 3
8.1 Platinum Crucibles, 30 mL.
sample and fused in a muffle for 25 min at 950°C. The sample
8.2 Balance, analytical type, precision to 0.1 mg.
is cooled, dissolved in hydrochloric acid, and diluted to
appropriate volume for analyses. 8.3 Furnace, with heating capacity to 1000°C.
8.4 Crucible Tongs, (cannot be made of iron, unless using
4.3 The second practice described in this standard involves
platinum-clad tips).
fusion of the sample with potassium hydroxide (KOH) or
sodium peroxide (Na O ) using an electric Bunsen burner,
2 2
8.5 Polytetrafluoroethylene (PTFE) Beaker, 125-mL capac-
dissolving the fused sample in water and dilute HCl, and
ity.
making to volume for analysis.
8.6 Magnetic Stir Bar, PTFE-coated (0.32 to 0.64 cm).
4.4 Dissolution of the sample using a microwave oven is
8.7 Magnetic Stirrer.
described in the third practice. The ground sample is digested
in a microwave oven using a mixture of hydrofluoric (HF) and 8.8 Mortar and Pestle, agate or alumina (or equivalent
grinding apparatus).
nitric (HNO ) acids. Boric acid is added to the resulting
solution to complex excess fluoride ions.
8.9 Sieves,150µm(100mesh),asdescribedinSpecification
4.5 These three practices offer alternative dissolution meth- E11.
ods for a total analysis of a glass sample for major, minor, and
9. Reagents and Materials
radionuclide components.
9.1 Anhydrous Sodium Carbonate (Na CO ).
2 3
5. Reagents
9.2 Anhydrous Sodium Tetraborate (Na B O ).
2 4 7
5.1 Purity of Reagents—Reagent grade chemicals shall be
9.3 Sodium Nitrate (NaNO ).
used in all tests. Unless otherwise indicated, it is intended that
all reagents conform to the specifications of the Committee on 9.4 Hydrochloric Acid (HCl), 50 % (v/v), made from con-
centrated hydrochloric acid (sp gr 1.19) and water.
Analytical Reagents of the American Chemical Society.
5.2 Purity of Water—Unless otherwise indicated, references 9.5 Nitric Acid (HNO ), 50 % (v/v), made from concen-
trated nitric acid (sp gr 1.44) and water.
to water shall be understood to mean at least Type II reagent
water in conformance with Specification D1193.
10. Hazards and Precautions
PRACTICE 1—FUSION WITH SODIUM
10.1 Follow established laboratory practices when conduct-
TETRABORATE AND SODIUM CARBONATE
ing this procedure.
10.2 The operator should wear suitable protective gear
6. Scope
when handling chemicals.
6.1 This practice covers flux fusion sample decomposition
10.3 The dilution of concentrated acids is conducted in
and dissolution for the determination of SiO and many other
fume hoods by cautiously adding an equal part acid to an equal
part of deionized water slowly and with constant stirring.
Reagent Chemicals, American Chemical Society Specifications, American
Chemical Society, Washington, DC. For suggestions on the testing of reagents not
10.4 Samples that are known or suspected to contain radio-
listed by the American Chemical Society, see Analar Standards for Laboratory
active materials must be handled with the appropriate radiation
Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
control and protection as prescribed by site health physics and
and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,
MD. radiation protection policies.
C1463 − 19
10.5 Samples that are known or suspected to contain toxic, lytes. Since the preparation alone does not produce any results,
hazardous, or radioactive materials must be handled to mini- the user must determine the precision and bias resulting from
mize or eliminate employee exposure. Fusion and leaching of this preparation and subsequent analysis.
the fused samples must be performed in a fume hood,
13.2 SeeAppendixX1forexamplesofanalyticaldatausing
radiation-shielded facility, or other appropriate containment.
solutions from this fusion.
11. Sample Preparation
PRACTICE 2—FUSION WITH POTASSIUM
11.1 If the material to be analyzed is not in powder form, it HYDROXIDE OR SODIUM PEROXIDE
should first be broken into small pieces by placing the sample
in a plastic bag and then striking the sample with a hammer. 14. Scope
The sample should then be ground to pass a 150 µm (100-
14.1 This practice covers alkaline fusion of silicate matrix
mesh) sieve using a clean mortar and pestle such as agate or
samples (or other matrices difficult to dissolve in acids) using
alumina.
an electric Bunsen burner mounted on an orbital shaker. This
practice has been used successfully to dissolve borosilicate
12. Procedure
glass,driedglassmelterfeeds,varioussimulatednuclearwaste
12.1 Weigh 50 to 250 mg of a powdered sample into a
forms, and dried soil samples.
platinum crucible on an analytical balance to 60.1 mg. The
14.2 This fusion apparatus and the alkaline fluxes described
sample size is dependent on the analyte concentration.
are suitable for use in shielded radiation containment facilities
NOTE 1—Although the larger sample size has generally worked well,
such as hot cells and shielded hoods.
somematricesmaynotdissolveentirely,andasmallersamplesizemaybe
necessary. 14.3 When samples dissolved using this practice are
radioactive, the user must follow radiation protection guide-
12.2 Add0.5 60.005geachofNa CO andNa B O tothe
2 3 2 4 7
lines in place for such materials.
crucible containing the sample.
12.3 Stir the sample/flux mixture in the crucible with a
15. Summary of Practice
spatula until a mixture is obtained. Prepare a reagent blank.
15.1 An aliquot of the dried and ignited sample is weighed
12.4 For samples containing minor to major elements that
into a tared nickel or zirconium metal crucible and an appro-
do not oxidize readily (such as Pb, Fe, etc.), add 300 mg of
priate amount of alkaline flux (potassium hydroxide or sodium
sodium nitrate. If desired, a Pt lid can be placed on the crucible
peroxide) is added. The crucible is placed on a preheated
to reduce splattering. When adding nitrate, 50 % v/v HNO
electric Bunsen burner (1000°C capability) mounted on an
should be the diluting acid in order to reduce the attack on
orbital shaker. The speed of the shaker is adjusted so that the
platinum in 12.6.
liquefied alkali metal flux and the sample are completely fused
12.5 Using the crucible tongs, place the crucible containing at the bottom of the crucible. When the fusion is complete
the sample/flux mixture into a muffle furnace for 25 min at a (about 5 min), the crucible is removed from the heater and
temperature of 950°C. Remove the crucible from the furnace cooled to room temperature. The fused mixture is dissolved in
and allow the melt to cool to room temperature. water, acidified with hydrochloric acid, and diluted to an
appropriate volume for subsequent analysis.
12.6 Placeastirbarineachcrucibleandadd4mL50 %v/v
HCl, and then dilute with H O to near the top of the crucible. 15.2 With appropriate sample preparation, the solution re-
sulting from this procedure can be analyzed for trace metals by
NOTE 2—In some cases, 50 % v/v HNO may be more appropriate than
ICP-AES, ICP-MS, and AAS, and for radionuclides using
HCl (that is, samples for ICP-MS, high lead samples, or when sodium
applicable radiochemical methods.
nitrate was added).
12.7 Place the crucible on the magnetic stirrer, and stir until
16. Significance and Use
the sample melt is dissolved completely (approximately 30
min). If undissolved material remains, the fusions described in 16.1 This practice describes a method to fuse and dissolve
Section 22 may need to be tried for cross correlation. silicate and refractory matrix samples for subsequent analysis
for trace metals and radionuclides. These samples may contain
12.8 To a calibrated volumetric flask, typically 100, 250,
high-level radioactive nuclear waste. Nuclear waste glass
500, or 1000 mL, add enough 1:1 HCl to make the final
vitrification plant feeds and product can be characterized using
concentration 2 % (including the acid already in the crucible).
this dissolution method followed by the appropriate analysis of
The final volume is determined by the expected analyte
the resulting solutions. Other matrices such as soil and sedi-
concentrations.Quantitativelytransferthesamplesolution,and
ment samples and geological samples may be totally dissolved
dilute.
using this practice.
12.9 The dilution volume is determined by the user of the
16.2 This practice has been used to analyze round-robin
practice and is dependent upon the desired analysis.
simulated nuclear waste glass samples.
13. Precision and Bias
16.3 This practice can be used for bulk analysis of glass
13.1 This practice addresses only the preparation steps in samples for the product consistency test (PCT) as described in
the overall preparation and measurement of the sample ana- Test Methods C1285 and for the analysis of monolithic
C1463 − 19
radioactivewasteglassusedinthestaticleachtestasdescribed 19. Reagents and Materials
in Test Method C1220.
19.1 Purity of Reagents—Allchemicalsusedinthispractice
16.4 This practice can be used to dissolve the glass refer- are to be reagent grade. Unless otherwise indicated all reagents
ence and testing materials described in Refs (1) and (2). shall conform to the specifications of the Committee on
Analytical Reagents of the American Chemical Society.
17. Interferences
19.2 Purity of Water—Unless otherwise indicated, refer-
17.1 Elements that form volatile species under these alka-
ences to water shall be understood to mean at least Type II
line fusion conditions will be lost during the fusion process.
reagent water conforming to Specification D1193.
17.2 Thehighalkalimetal(NaorK)contentoftheresulting
19.3 Potassium Hydroxide (KOH), pellet.
samplesolutionscancauseinterferencewithICPnebulizerand
19.4 Potassium Nitrate (KNO ), crystal.
torch assemblies due to salt deposition. Dilution of the sample
solutions may be necessary. 19.5 Sodium Peroxide (Na O ), granular.
2 2
19.6 Hydrochloric Acid (HCl), concentrated, sp gr 1.19.
17.3 The metallic impurities, that is, Na, K, in the alkaline
fluxusedtofusethesamplescancauseapositivebiasifproper
19.7 Nitric Acid Solution (2 vol %)—Add 20 mL of con-
corrections are not applied. Method blanks must be determined
centrated nitric acid (HNO , sp gr 1.42) to 950 mL of water
to allow correction for flux impurity concentration.
while stirring. Make to 1 Lvolume and store in a polyethylene
bottle.
18. Apparatus
19.8 Oxalic Acid, crystals.
18.1 Analytical Balance, capable of weighing to 60.1 mg.
20. Hazards and Precautions
18.2 Electric Bunsen Burner, capable of heating to 1000°C
to accommodate the larger size (100 mL nickel) metal
20.1 Samples that are known or suspected to contain radio-
crucibles, the heat shield on top of the electric Bunsen Burner
active materials must be handled with the appropriate radiation
is wrapped with a noncorrosive wire such as inconel at three
control and protection as prescribed by site health physics and
evenly distributed locations. With the wire on the heat shield,
radiation protection policies.
the large size crucibles are better supported and more easily
20.2 Samples that are known or suspected to contain toxic,
removed. A wire basket made from the noncorrosive wire is
hazardous, or radioactive materials must be handled to mini-
alsofabricatedsothatsmallersizecrucibles(55mLzirconium)
mize or eliminate employee exposure. Fusion and leaching of
that pass through the heat shield are supported evenly in the
the fused samples must be performed in a fume hood,
heatingmandreloftheelectricBunsenburner.Fig.1showsthe
radiation-shielded facility, or other appropriate containment.
electric Bunsen burner mounted on the orbital shaker with the
Personalprotectiveequipmentmustbewornwhenappropriate.
above modifications for crucible mounting.
All site good laboratory safety and industrial hygiene practices
18.3 Orbital Shaker, including a holder fabricated to fasten
must be followed.
the electric Bunsen burner on the platform (see Fig. 1).
20.3 Sodium peroxide is a strong oxidizer. Precaution must
18.4 Manual Adjustable Power Supply, for controlling the
be taken when fusions are performed on samples containing
temperature of the electric Bunsen burner.
materials that are readily oxidized.
18.5 Zirconium Metal Crucible, 55 mLcapacity, high form.
20.4 Samples containing significant concentrations of phos-
Different shape and capacity crucibles also may be used when
phates (greater than 5 %) cannot be fused in a zirconium metal
necessary.
crucible using sodium peroxide. The phosphate destroys the
oxide layer on the crucible, resulting in severe corrosion.
18.6 Nickel Metal Crucible, 100 mL capacity, high form.
Aluminum oxide crucibles can be substituted for fusion of
Different shape and capacity crucibles also may be used when
samples containing phosphates greater than 5 %.
necessary.
21. Sample Preparation
18.7 Aluminum Oxide Crucible, 55 mL capacity. Different
shape and capacity may be used depending upon sample sizes
21.1 Wet or Slurry Samples:
taken.
21.1.1 Dry wet or slurry samples in a tared porcelain
crucibleat105°C.Grindthedriedsampleinaporcelainmortar
18.8 Sieve, 75 µm (200 Mesh), as described in Specification
to a particle size to pass a 75 µm (No. 200) sieve.
E11.
21.1.2 Weigh a portion (approximately 3 g) of the dried and
18.9 Hot Plate or Steam Bath, capable of heating to 100°C.
ground sample described in 21.1.1 to the nearest 0.001 g in a
tared porcelain crucible. Ignite the sample at 1000°C and
The boldface numbers in parentheses refer to the list of references at the end of
determine the sample loss on ignition factor (I ), where:
F
this practice.
I 5 ~W 2 W !/~W ! (1)
Electric Bunsen burners are available from most major laboratory supply
F i f i
houses.
where:
Orbital shaker, Model 04732-00 available from Cole-Parmer Instrument
Company, has been found to be suitable for this purpose.
W = initial sample weight, and
i
The Model 01575-26 power supply available from Cole-Parmer Instrument
W = sample weight after ignition.
f
Company has been found to be suitable for this purpose.
C1463 − 19
FIG. 1 Electric Bunsen Burner Mounted on the Orbital Shaker
21.2 Dry Solid or Oxide Samples: 22.1.6 Reagent grade KOH will contain trace amounts of
21.2.1 Grind the dry solid or oxide sample to a particle size sodium as an impurity. A correction for this flux impurity
to pass a 75 µm (No. 200) sieve.
should be made to the sodium found in the sample.
21.2.2 Weigh a portion (approximately 3 g) of the ground
22.1.7 Set the crucible on the preheated electric Bunsen
sample described in 21.2.1 to the nearest 0.001 g in a tared
burner and turn on the orbital shaker.
porcelain crucible. Ignite the sample at 1000°C and determine
22.1.8 Fuse the sample mixture for approximately 5 min or
the ignition factor in accordance with equation 21.1.2
until the fusion is complete. If at the completion of the fusion
NOTE 3—The loss on ignition for dry solid or oxide samples may be or after about 5 min of heating, there is still undissolved
negligible.
material, remove the crucible from the burner, allow to cool,
and add 0.5 mL of water. Replace the crucible on the burner
22. Procedure
and continue fusion until dissolution is complete.
22.1 Potassium Hydroxide Fusion—The KOH fusion is
NOTE 4—During the KOH fusion, the flux will become more viscous as
performed in a nickel metal crucible.
thefusioncontinues.IfthetemperatureoftheelectricBunsenburnerisset
22.1.1 The choice of fusion methods described in 22.1 and
too high, the KOH will solidify before the fusion is complete. Once the
22.2 is determined by the analyte elements to be determined;
fusion mixture has solidified and the heating is continued, further
that is, if combinations of Na, K, Ni, or Zr are to be
dissolution of the sample ceases and some of the dissolved silicates in the
determined, then one or both of the fusion methods may have sample will dehydrate, resulting in incomplete dissolution of the fused
sample.
to be performed.
22.1.2 Set the manually adjustable power controller that
22.1.9 When fusion is complete, remove the crucible from
supplies power to the electric Bunsen burner so that 1.6 g of
the burner and allow to cool to room temperature.
NaOH in a zirconium crucible will melt within 1 to 2 min.
22.1.10 Add water drop-wise to the crucible until the initial
22.1.3 Tare a nickel metal crucible to the nearest 0.001 g.
vigorousreactionsubsides.Addatotalofabout10mLofwater
22.1.4 Weigh an aliquot of the ground s
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C1463 − 13 C1463 − 19
Standard Practices for
Dissolving Glass Containing Radioactive and Mixed Waste
for Chemical and Radiochemical Analysis
This standard is issued under the fixed designation C1463; 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
1.1 These practices cover techniques suitable for dissolving glass samples that may contain nuclear wastes. These techniques
used together or independently will produce solutions that can be analyzed by inductively coupled plasma atomic emission
spectroscopy (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS), atomic absorption spectrometry (AAS),
radiochemical methods and wet chemical techniques for major components, minor components and radionuclides.
1.2 One of the fusion practices and the microwave practice can be used in hot cells and shielded hoods after modification to
meet local operational requirements.
1.3 The user of these practices must follow radiation protection guidelines in place for their specific laboratories.
1.4 Additional information relating to safety is included in the text.
1.5 The dissolution techniques described in these practices can be used for quality control of the feed materials and the product
of plants vitrifying nuclear waste materials in glass.
1.6 These practices are introduced to provide the user with an alternative means to Test Methods C169 for dissolution of waste
containing glass in shielded facilities. Test Methods C169 is not practical for use in such facilities and with radioactive materials.
1.7 The ICP-AES methods in Test Methods C1109 and C1111 can be used to analyze the dissolved sample with additional
sample preparation as necessary and with matrix effect considerations. Additional information as to other analytical methods can
be found in Test Method C169.
1.8 Solutions from this practice may be suitable for analysis using ICP-MS after establishing laboratory performance
criteria.criteria and verification that the criteria can be met. For example, Test Methods C1287 or C1637 may be used with
additional sample preparation as necessary and appropriate matrix effect considerations.
1.9 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this
standard.Units in parentheses are for information only.
1.10 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use. Specific precautionary statements are given in Sections 10, 20, and 30.
1.11 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.
2. Referenced Documents
2.1 ASTM Standards:
C169 Test Methods for Chemical Analysis of Soda-Lime and Borosilicate Glass
C859 Terminology Relating to Nuclear Materials
C1109 Practice for Analysis of Aqueous Leachates from Nuclear Waste Materials Using Inductively Coupled Plasma-Atomic
Emission Spectroscopy
C1111 Test Method for Determining Elements in Waste Streams by Inductively Coupled Plasma-Atomic Emission Spectroscopy
These practices are under the jurisdiction of ASTM Committee C26 on Nuclear Fuel Cycle and are the direct responsibility of Subcommittee C26.05 on Methods of Test.
Current edition approved July 1, 2013Feb. 1, 2019. Published July 2013February 2019. Originally approved in 2000. Last previous edition approved in 20072013 as
C1463 – 00 (2007).C1463 – 13. DOI: 10.1520/C1463-13.10.1520/C1463-19.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1463 − 19
C1220 Test Method for Static Leaching of Monolithic Waste Forms for Disposal of Radioactive Waste
C1285 Test Methods for Determining Chemical Durability of Nuclear, Hazardous, and Mixed Waste Glasses and Multiphase
Glass Ceramics: The Product Consistency Test (PCT)
C1287 Test Method for Determination of Impurities in Nuclear Grade Uranium Compounds by Inductively Coupled Plasma
Mass Spectrometry
C1637 Test Method for the Determination of Impurities in Plutonium Metal: Acid Digestion and Inductively Coupled
Plasma-Mass Spectroscopy (ICP-MS) Analysis
D1193 Specification for Reagent Water
E11 Specification for Woven Wire Test Sieve Cloth and Test Sieves
3. Terminology
3.1 For definitions of terms used in this Practice, refer to Terminology C859.
4. Summary of Practice
4.1 The three practices for dissolving silicate matrix samples each require the sample to be dried and ground to a fine powder.
4.2 In the first practice, a mixture of sodium tetraborate (Na B O ) and sodium carbonate (Na CO ) is mixed with the sample
2 4 7 2 3
and fused in a muffle for 25 min at 950°C. The sample is cooled, dissolved in hydrochloric acid, and diluted to appropriate volume
for analyses.
4.3 The second practice described in this standard involves fusion of the sample with potassium hydroxide (KOH) or sodium
peroxide (Na O ) using an electric Bunsen burner, dissolving the fused sample in water and dilute HCl, and making to volume for
2 2
analysis.
4.4 Dissolution of the sample using a microwave oven is described in the third practice. The ground sample is digested in a
microwave oven using a mixture of hydrofluoric (HF) and nitric (HNO ) acids. Boric acid is added to the resulting solution to
complex excess fluoride ions.
4.5 These three practices offer alternative dissolution methods for a total analysis of a glass sample for major, minor, and
radionuclide components.
5. Reagents
5.1 Purity of Reagents—Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all
reagents conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society.
5.2 Purity of Water—Unless otherwise indicated, references to water shall be understood to mean at least Type II reagent water
in conformance with Specification D1193.
PRACTICE 1—FUSION WITH SODIUM TETRABORATE AND SODIUM CARBONATE
6. Scope
6.1 This practice covers flux fusion sample decomposition and dissolution for the determination of SiO and many other oxides
in glasses, ceramics, and raw materials. The solutions are analyzed by atomic spectroscopy methods. Analyte concentrations
ranging from trace to major levels can be measured in these solutions, depending on the sample weights and dilution volumes used
during preparation.
7. Technical Precautions
7.1 This procedure is not useful for the determination of boron or sodium since these elements are contained in the flux material.
7.2 The user is cautioned that with analysis by ICP-AES, AAS, and ICP-MS, the high sodium concentrations from the flux may
cause interferences.
7.3 Elements that form volatile species under these alkaline fusion conditions may be lost during the fusion process (that is, As
and Sb).
8. Apparatus
8.1 Platinum Crucibles, 30 mL.
8.2 Balance, analytical type, precision to 0.1 mg.
Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For suggestions on the testing of reagents not listed by
the American Chemical Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and National
Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.
C1463 − 19
8.3 Furnace, with heating capacity to 1000°C.
8.4 Crucible Tongs, (cannot be made of iron, unless using platinum-clad tips).
8.5 Polytetrafluoroethylene (PTFE) Beaker, 125-mL capacity.
8.6 Magnetic Stir Bar, PTFE-coated (0.32 to 0.64 cm).
8.7 Magnetic Stirrer.
8.8 Mortar and Pestle, agate or alumina (or equivalent grinding apparatus).
8.9 Sieves, 100 mesh.150 μm (100 mesh), as described in Specification E11.
9. Reagents and Materials
9.1 Anhydrous Sodium Carbonate (Na CO ).
2 3
9.2 Anhydrous Sodium Tetraborate (Na B O ).
2 4 7
9.3 Sodium Nitrate (NaNO ).
9.4 Hydrochloric Acid (HCl), 50 % (v/v), made from concentrated hydrochloric acid (sp gr 1.19) and water.
9.5 Nitric Acid (HNO ), 50 % (v/v), made from concentrated nitric acid (sp gr 1.44) and water.
10. Hazards and Precautions
10.1 Follow established laboratory practices when conducting this procedure.
10.2 The operator should wear suitable protective gear when handling chemicals.
10.3 The dilution of concentrated acids is conducted in fume hoods by cautiously adding an equal part acid to an equal part of
deionized water slowly and with constant stirring.
10.4 Samples that are known or suspected to contain radioactive materials must be handled with the appropriate radiation
control and protection as prescribed by site health physics and radiation protection policies.
10.5 Samples that are known or suspected to contain toxic, hazardous, or radioactive materials must be handled to minimize
or eliminate employee exposure. Fusion and leaching of the fused samples must be performed in a fume hood, radiation-shielded
facility, or other appropriate containment.
11. Sample Preparation
11.1 If the material to be analyzed is not in powder form, it should first be broken into small pieces by placing the sample in
a plastic bag and then striking the sample with a hammer. The sample should then be ground to pass a 100-mesh 150 μm
(100-mesh) sieve using a clean mortar and pestle such as agate or aluminaalumina.
12. Procedure
12.1 Weigh 50 to 250 mg of a powdered sample into a platinum crucible on an analytical balance to 60.1 mg. The sample size
is dependent on the analyte concentration.
NOTE 1—Although the larger sample size has generally worked well, some matrices may not dissolve entirely. Try smaller sample sizes if that is the
case.entirely, and a smaller sample size may be necessary.
12.2 Add 0.5 6 0.005 g each of Na CO and Na B O to the crucible containing the sample.
2 3 2 4 7
12.3 Stir the sample/flux mixture in the crucible with a spatula until a mixture is obtained. Prepare a reagent blank.
12.4 For samples containing minor to major elements that do not oxidize readily (such as Pb, Fe, etc.), add 300 mg of sodium
nitrate. If desired, a Pt lid can be placed on the crucible to reduce splattering. When adding nitrate, 50 % v/v HNO should be the
diluting acid in order to reduce the attack on platinum in 12.6.
12.5 Using the crucible tongs, place the crucible containing the sample/flux mixture into a muffle furnace for 25 min at a
temperature of 950°C. Remove the crucible from the furnace and allow the melt to cool to room temperature.
12.6 Place a stir bar in each crucible and add 4 mL 50 % v/v HCl, and then dilute with H O to near the top of the crucible.
NOTE 2—In some cases, 50 % v/v HNO may be more appropriate than HCl (that is, samples for ICP-MS, high lead samples, or when sodium nitrate
was added).
12.7 Place the crucible on the magnetic stirrer, and stir until the sample melt is dissolved completely (approximately 30 min).
If undissolved material remains, the fusions described in Section 22 may need to be tried for cross correlation.
12.8 To a calibrated volumetric flask, typically 100, 250, 500, or 1000 mL, add enough 1:1 HCl to make the final concentration
2 % (including the acid already in the crucible). The final volume is determined by the expected analyte concentrations.
Quantitatively transfer the sample solution, and dilute.
C1463 − 19
12.9 The dilution volume is determined by the user of the practice and is dependent upon the desired analysis.
13. Precision and Bias
13.1 This practice addresses only the preparation steps in the overall preparation and measurement of the sample analytes. Since
the preparation alone does not produce any results, the user must determine the precision and bias resulting from this preparation
and subsequent analysis.
13.2 See Appendix X1 for examples of analytical data using solutions from this fusion.
PRACTICE 2—FUSION WITH POTASSIUM HYDROXIDE OR SODIUM PEROXIDE
14. Scope
14.1 This practice covers alkaline fusion of silicate matrix samples (or other matrices difficult to dissolve in acids) using an
electric Bunsen burner mounted on an orbital shaker. This practice has been used successfully to dissolve borosilicate glass, dried
glass melter feeds, various simulated nuclear waste forms, and dried soil samples.
14.2 This fusion apparatus and the alkaline fluxes described are suitable for use in shielded radiation containment facilities such
as hot cells and shielded hoods.
14.3 When samples dissolved using this practice are radioactive, the user must follow radiation protection guidelines in place
for such materials.
15. Summary of Practice
15.1 An aliquot of the dried and ignited sample is weighed into a tared nickel or zirconium metal crucible and an appropriate
amount of alkaline flux (potassium hydroxide or sodium peroxide) is added. The crucible is placed on a preheated electric Bunsen
burner (1000°C capability) mounted on an orbital shaker. The speed of the shaker is adjusted so that the liquefied alkali metal flux
and the sample are completely fused at the bottom of the crucible. When the fusion is complete (about 5 min), the crucible is
removed from the heater and cooled to room temperature. The fused mixture is dissolved in water, acidified with hydrochloric acid,
and diluted to an appropriate volume for subsequent analysis.
15.2 With appropriate sample preparation, the solution resulting from this procedure can be analyzed for trace metals by
ICP-AES, ICP-MS, and AAS, and for radionuclides using applicable radiochemical methods.
16. Significance and Use
16.1 This practice describes a method to fuse and dissolve silicate and refractory matrix samples for subsequent analysis for
trace metals and radionuclides. These samples may contain high-level radioactive nuclear waste. Nuclear waste glass vitrification
plant feeds and product can be characterized using this dissolution method followed by the appropriate analysis of the resulting
solutions. Other matrices such as soil and sediment samples and geological samples may be totally dissolved using this practice.
16.2 This practice has been used to analyze round-robin simulated nuclear waste glass samples.
16.3 This practice can be used for bulk analysis of glass samples for the product consistency test (PCT) as described in Test
Methods C1285 and for the analysis of monolithic radioactive waste glass used in the static leach test as described in Test Method
C1220.
16.4 This practice can be used to dissolve the glass reference and testing materials described in Refs (1) and (2).
17. Interferences
17.1 Elements that form volatile species under these alkaline fusion conditions will be lost during the fusion process.
17.2 The high alkali metal (Na or K) content of the resulting sample solutions can cause interference with ICP nebulizer and
torch assemblies due to salt deposition. Dilution of the sample solutions may be necessary.
17.3 The metallic impurities, that is, Na, K, in the alkaline flux used to fuse the samples can cause a positive bias if proper
corrections are not applied. Method blanks must be determined to allow correction for flux impurity concentration.
18. Apparatus
18.1 Analytical Balance, capable of weighing to 6 0.1 60.1 mg.
18.2 Electric Bunsen Burner, capable of heating to 1000°C.1000°C to accommodate the larger size (100 mL nickel) metal
crucibles, the heat shield on top of the electric Bunsen Burner is wrapped with a noncorrosive wire such as inconel at three evenly
distributed locations. With the wire on the heat shield, the large size crucibles are better supported and more easily removed. A
The boldface numbers in parentheses refer to the list of references at the end of this practice.
Electric Bunsen burners are available from most major laboratory supply houses.
C1463 − 19
wire basket made from the noncorrosive wire is also fabricated so that smaller size crucibles (55 mL zirconium) that pass through
the heat shield are supported evenly in the heating mandrel of the electric Bunsen burner. Fig. 1 shows the electric Bunsen burner
FIG. 1 Electric Bunsen Burner Mounted on the Orbital Shaker
mounted on the orbital shaker with the above modifications for crucible mounting.
18.3 Orbital Shaker, including a holder fabricated to fasten the electric Bunsen burner on the platform (see Fig. 1).
18.4 Manual Adjustable Power Supply, for controlling the temperature of the electric Bunsen burner.
18.5 Zirconium Metal Crucible, 55 mL capacity, high form. Different shape and capacity crucibles also may be used when
necessary.
18.6 Nickel Metal Crucible, 100 mL capacity, high form. Different shape and capacity crucibles also may be used when
necessary.
18.7 Aluminum Oxide Crucible, 55 mL capacity. Different shape and capacity may be used depending upon sample sizes taken.
18.8 200 Mesh (74 um) Sieve.Sieve, 75 μm (200 Mesh), as described in Specification E11.
18.9 Hot Plate or Steam Bath, capable of heating to 100°C.
19. Reagents and Materials
19.1 Purity of Reagents—All chemicals used in this practice are to be reagent grade. Unless otherwise indicated all reagents
shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society.
19.2 Purity of Water—Unless otherwise indicated, references to water shall be understood to mean at least Type II reagent water
conforming to Specification D1193.
19.3 Potassium Hydroxide (KOH), pellet.
19.4 Potassium Nitrate (KNO ), crystal.
19.5 Sodium Peroxide (Na O ), granular.
2 2
19.6 Hydrochloric Acid (HCl), concentrated, sp gr 1.19.
19.7 Nitric Acid Solution (2 vol %)—Add 20 mL of concentrated nitric acid (HNO , sp gr 1.42) to 950 mL of water while
stirring. Make to 1 L volume and store in a polyethylene bottle.
Orbital shaker, Model 04732-00 available from Cole-Parmer Instrument Company, has been found to be suitable for this purpose.
The Model 01575-26 power supply available from Cole-Parmer Instrument Company has been found to be suitable for this purpose.
C1463 − 19
19.8 Oxalic Acid, crystals.
20. Hazards and Precautions
20.1 Samples that are known or suspected to contain radioactive materials must be handled with the appropriate radiation
control and protection as prescribed by site health physics and radiation protection policies.
20.2 Samples that are known or suspected to contain toxic, hazardous, or radioactive materials must be handled to minimize
or eliminate employee exposure. Fusion and leaching of the fused samples must be performed in a fume hood, radiation-shielded
facility, or other appropriate containment. Personal protective equipment must be worn when appropriate. All site good laboratory
safety and industrial hygiene practices must be followed.
20.3 Sodium peroxide is a strong oxidizer. Precaution must be taken when fusions are performed on samples containing
materials that are readily oxidized.
20.4 Samples containing significant concentrations of phosphates (greater than 5 %) cannot be fused in a zirconium metal
crucible using sodium peroxide. The phosphate destroys the oxide layer on the crucible, resulting in severe corrosion. Aluminum
oxide crucibles can be substituted for fusion of samples containing phosphates greater than 5 %.
21. Sample Preparation
21.1 Wet or Slurry Samples:
21.1.1 Dry wet or slurry samples in a tared porcelain crucible at 105°C. Grind the dried sample in a porcelain mortar to a particle
size to pass a No. 200 (74 μm)75 μm (No. 200) sieve.
21.1.2 Weigh a portion (approximately 3 g) of the dried and ground sample described in 21.1.1 to the nearest 0.001 g in a tared
porcelain crucible. Ignite the sample at 1000°C and determine the sample loss on ignition factor (I ), where:
F
I 5 ~W 2 W !/~W ! (1)
F i f i
where:
W = initial sample weight, and
i
W = sample weight after ignition.
f
21.2 Dry Solid or Oxide Samples:
21.2.1 Grind the dry solid or oxide sample to a particle size to pass a No. 200 (74 μm)75 μm (No. 200) sieve.
21.2.2 Weigh a portion (approximately 3 g) of the ground sample described in 21.2.1 to the nearest 0.001 g in a tared porcelain
crucible. Ignite the sample at 1000°C and determine the ignition factor in accordance with equation 21.1.2
NOTE 3—The loss on ignition for dry solid or oxide samples may be negligible.
22. Procedure
22.1 Potassium Hydroxide Fusion—The KOH fusion is performed in a nickel metal crucible.
22.1.1 The choice of fusion methods described in 22.1 and 22.2 is determined by the analyte elements to be determined; that
is, if combinations of Na, K, Ni, or Zr are to be determined, then one or both of the fusion methods may have to be performed.
22.1.2 Set the manually adjustable power controller that supplies power to the electric Bunsen burner so that 1.6 g of NaOH
in a zirconium crucible will melt within 1 to 2 min.
22.1.3 Tare a nickel metal crucible to the nearest 0.001 g.
22.1.4 Weigh an aliquot of the ground sample described in 21.1.1 or 21.2.1, which is equivalent to 0.3506 0.350 6 0.050 g
of ignited sample (21.1.2 or 21.2.2). Determine the amount of dried sample (W ) to be aliquoted by using the ignition factor from
s
21.1.2 as follows:
W 5 0.350 g / 12 I (2)
~ ! ~ !
s F
22.1.5 Add 1.600 6 0.200 g of KOH pellets. Record the weight of KOH added to the crucible to the nearest 0.001 g. Swirl the
crucible to mix the sample and the KOH pellets completely.
22.1.6 Reagent grade KOH will contain trace amounts of sodium as an impurity. A correction for this flux impurity should be
made to the sodium found in the sample.
22.1.7 Set the crucible on the preheated electric Bunsen burner and turn on the orbital shaker.
22.1.8 Fuse the sample mixture for approximately 5 min or until the fusion is complete. If at the completion of the fusion or
after about 5 min of heating, there is still undissolved material, remove the crucible from the burner, allow to cool, and add 0.5
mL of water. Replace the crucible on the burner and continue fusion until dissolution is complete.
NOTE 4—During the KOH fusion, the flux will become more viscous as the fusion continues. If the temperature of the electric Bunsen burner is set
too high, the KOH will solidify before the fusion is complete. Once the fusion mixture has solidified and the heating is continued, further d
...