ASTM C560-88(2005)e1
(Test Method)Standard Test Methods for Chemical Analysis of Graphite
Standard Test Methods for Chemical Analysis of Graphite
SIGNIFICANCE AND USE
These test methods provide a practical way to measure the concentration of certain trace elements in graphite. Many end uses of graphite require that it be free of elements which may be incompatible with certain nuclear applications. Other elemental contamination can affect the rate of oxidative degradation.
These test methods allow measurement of trace amounts of contaminants with a minimal amount of costly equipment. The colorimetric procedures used are accessible to most laboratories.
SCOPE
1.1 These test methods cover the chemical analysis of graphite.
1.2 The analytical procedures appear in the following order: Sections Silicon by the Molybdenum Blue (Colorimetric) Test Method8 to 14Iron by the o-Phenanthroline (Colorimetric) Test Method 15 to 21 Calcium by the Permanganate (Colorimetric) Test Method22 to 28 Aluminum by the 2-Quinizarin Sulfonic Acid Test Method29 to 35Titanium by the Peroxide (Colorimetric) Test Method 36 to 43 Vanadium by the 3,3`-Dimethylnaphthidine (Colorimetric) Test Method 44 to 51 Boron by the Curcumin-Oxalic Acid (Colorimetric) Test Method52 to 59
1.3 The preferred concentration of sought element in the final solution, the limits of sensitivity, and the precision of the results are given in Table 1.
1.4 The values stated in SI units are to be regarded as the standard.
1.5 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 and health practices and determine the applicability of regulatory limitations prior to use. See 56.1 for specific caution statement.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information.
An American National Standard
´1
Designation:C560–88 (Reapproved 2005)
Standard Test Methods for
Chemical Analysis of Graphite
This standard is issued under the fixed designation C560; 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.
´ NOTE—Replaced the word “asbestos” in 25.7 editorially in August 2005.
TABLE 1 Concentration of Elements, Limits of Sensitivity, and
1. Scope
Reproducibility
1.1 These test methods cover the chemical analysis of
graphite.
Concentration Reproducibility,
Range, µg/mL Sensitivity Limit, Relative, %
1.2 The analytical procedures appear in the following order:
Element Solution µg/mL Solution (s/x 3 100)
Sections
Silicon 10 to 100 µg/100 mL 1 µg/100 mL 64
Silicon by the Molybdenum Blue (Colorimetric) Test Method 8 to 14
Iron 100 to 600 µg/100 mL 40 µg/100 mL 65
Ironbythe o-Phenanthroline (Colorimetric) Test Method 15 to 21
Calcium 600 to 3000 µg/100 mL 50 µg/100 mL 65
Calcium by the Permanganate (Colorimetric) Test Method 22 to 28
Aluminum 10 to 100 µg/100 mL 2 µg/100 mL 60.1
Aluminum by the 2-Quinizarin Sulfonic Acid Test Method 29 to 35
Titanium 600 to 3000 µg/100 mL 200 µg/100 mL 62
Titanium by the Peroxide (Colorimetric) Test Method 36 to 43
Vanadium 10 to 130 µg/50 mL 5 µg/50 mL 65
Vanadium by the 3,38-Dimethylnaphthidine (Colorimetric) Test
Boron 0.5 to 1.4 µg/50 mL 0.1 µg/50 mL 620
Method 44 to 51
Boron by the Curcumin-Oxalic Acid (Colorimetric) Test Method 52 to 59
1.3 The preferred concentration of sought element in the
end uses of graphite require that it be free of elements which
final solution, the limits of sensitivity, and the precision of the
may be incompatible with certain nuclear applications. Other
results are given in Table 1.
elemental contamination can affect the rate of oxidative deg-
1.4 The values stated in SI units are to be regarded as the
radation.
standard.
3.2 Thesetestmethodsallowmeasurementoftraceamounts
1.5 This standard does not purport to address all of the
of contaminants with a minimal amount of costly equipment.
safety concerns, if any, associated with its use. It is the
The colorimetric procedures used are accessible to most
responsibility of the user of this standard to establish appro-
laboratories.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use. See 56.1 for
4. Reagents
specific caution statement.
4.1 Purity of Reagents—Reagent grade chemicals shall be
2. Referenced Documents
used in all tests. Unless otherwise indicated, it is intended that
all reagents shall conform to the specifications of the Commit-
2.1 ASTM Standards:
tee onAnalytical Reagents of theAmerican Chemical Society,
C561 Test Method for Ash in a Graphite Sample
where such specifications are available. Other grades may be
D1193 Specification for Reagent Water
used, provided it is first ascertained that the reagent is of
E29 Practice for Using Significant Digits in Test Data to
sufficiently high purity to permit its use without lessening the
Determine Conformance with Specifications
accuracy of the determination.
3. Significance and Use
4.2 When available, National Institute of Standards and
Technology (NIST) certified reagents should be used as stan-
3.1 These test methods provide a practical way to measure
dards in preparing calibration curves.
the concentration of certain trace elements in graphite. Many
4.3 Unless otherwise indicated, references to water shall be
understood to mean reagent water conforming to Specification
These test methods are under the jurisdiction of ASTM Committee D02 on
D1193.
Petroleum Products and Lubricants and are the direct responsibility of Subcommit-
tee D02.F0 on Manufactured Carbon and Graphite Products.
Current edition approved May 1, 2005. Published May 2005. Originally
approved in 1965. Last previous edition approved in 1998 as C560 – 88 (1998). Reagent Chemicals, American Chemical Society Specifications, American
DOI: 10.1520/C0560-88R05E01. Chemical Society, Washington, DC. For suggestions on the testing of reagents not
For referenced ASTM standards, visit the ASTM website, www.astm.org, or listed by the American Chemical Society, see Analar Standards for Laboratory
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
Standards volume information, refer to the standard’s Document Summary page on and National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,
the ASTM website. MD.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
´1
C560–88 (2005)
4.4 National Institute of Standards and Technology certified 11.4 Silicon, Working Solution (1 mL= 0.01 mg Si)—Dilute
reagents specified in certain steps of this procedure may no 10 mL of standard silicon solution (1 mL = mg Si) to 1 L in a
longerbeavailable.IfNISTreagentsarenotavailable,thenthe volumetric flask. Transfer to a polyethylene bottle.
highest purity reagent grade shall be substituted.
11.5 Sodium Carbonate Solution (100 g/L)—Dissolve100g
ofsodiumcarbonate(Na CO )inwateranddiluteto1L.Store
2 3
5. Sampling
in a polyethylene bottle.
5.1 The entire sample of graphite should be crushed and 11.6 Stannous Chloride Solution—Dissolve 2.5 g of stan-
ground to pass a No. 60 (250-µm) sieve in a roll crusher. The
nous chloride (SnCl ·2H O) in 5 mL of hot concentrated HCl
2 2
sample may have been reduced in size initially by drilling the (sp gr 1.19) and dilute to 250 mL with water. Prepare a fresh
test bar with silicon carbide-tipped drills.
solution every 2 weeks.
11.7 Sulfuric Acid (H SO ) (1+3)—Carefully mix 1 volume
2 4
6. Rounding Calculated Values
of concentrated H SO , sp gr 1.84 with 3 volumes of water.
2 4
6.1 Calculated values shall be rounded to the desired num-
ber of places in accordance with Practice E29. 12. Preparation of Calibration Curve
12.1 Calibration Solutions—Transfer 0, 1.0, 3.0, 5.0, 7.0,
7. Precision and Bias
and 10 mL of silicon working solution (1 mL = 0.01 mg Si) to
7.1 No statement is being made about either the precision or
100-mL volumetric flasks. Add 5 drops of H SO (1+3) and
2 4
bias of these test methods. At this time Committee C05 is
dilute to approximately 10 mL.
investigating new standard methods of chemical analysis of
12.2 Color Development—Add 2.5 mL of (NH ) Mo O
4 6 7 24
graphite that will eventually replace these test methods. For
solution to each flask and let stand 5 min. Then add 5.0 mL of
this reason, no statistical study of these test methods has been
H SO (1+3), mix well, and add 5 drops of SnCl solution.
2 4 2
planned.
Dilute to volume and let stand 5 min.
7.2 The relative reproducibility data in Table 1 has no
12.3 Photometry—Transfer a suitable portion of the reagent
supportive research report on file and does not conform to
blank solution to a 1-cm absorption cell and adjust the
ASTM precision and bias standards.
photometertotheinitialsetting,usingawavelengthof765nm.
While maintaining this photometer adjustment, take the pho-
SILICON BY THE MOLYBDENUM BLUE TEST
tometric readings of the calibration solutions.
METHOD
12.4 Calibration Curve—Plot the photometric readings (ab-
sorbance) of the calibration solution against micrograms of
8. Summary of Test Method
silicon per 100 mL of solution.
8.1 Silicomolybdic acid is formed by adding ammonium
molybdate to soluble silicates in acid solution. The heteropoly
13. Procedure for Carbonate Fusion
acid is reduced with stannous chloride to form a deep blue
colloidal solution. Photometric measurement is made at 765 13.1 Sample Solution—Rinse the ash (from a 50 to 75-g ash
nm. Regular classical gravimetric methods for silica using sample)fromtheplatinumdishintoamullitemortarwiththree
sodium carbonate fusion followed by hydrofluoric acid vola- 0.5-g portions of Na CO passing a No. 100 (150-µm) sieve
2 3
tilization may be suitable for use. (see Test Method C561). Grind the resulting mixture to pass a
No. 200 (75-µm) sieve to ensure intimate contact of the ash
9. Stability of Color
with the flux. Then transfer the mixture to a platinum crucible
(containing 0.5 g of Na CO ) with three 0.5-g rinses of
9.1 The blue colored solution should be disposed of and the
2 3
Na CO . Add sufficient Na CO to bring the total Na CO
determination repeated if a period of 12 h has elapsed between 2 3 2 3 2 3
content to 6 g. Cover the crucible, and fuse gently over a
color development and measurements.
bunsen burner.
10. Interferences
13.1.1 When fusion is complete (usually 30 min to 1 h),
removethecruciblefromtheburner,swirltodistributethemelt
10.1 There is no interference from the ions usually present
on the sides of the crucible, and allow to cool. Then place the
in graphite.
crucible and contents in a 200-mL high-form beaker and add
11. Reagents 25 mL of water. Cover the beaker with a watch glass, and
cautiously add HCl (1+1) to decompose the melt. When
11.1 Ammonium Molybdate (50 g/L)—Dissolve 50 g of
solution of the melt is complete, boil for several minutes on a
ammonium molybdate ((NH ) -Mo O ·4H O) in water and
4 6 7 24 2
hot plate and cool.
dilute to 1 L.
13.1.2 Transfer to a 100-mL volumetric flask, dilute to
11.2 Hydrochloric Acid (HCl) (1+1)—Mix equal volumes
volume, and mix. Transfer a suitable aliquot of this solution to
of concentrated HCl, sp gr 1.19 and water.
a 100-mL volumetric flask.
11.3 Silicon, Standard Solution (1 mL= 1 mg Si)—Dissolve
13.2 Color Development—Adjust the pH of the aliquot to 6
10.1 g of sodium silicate (Na SiO ·9H O) in water and dilute
2 3 2
to 8 with Na CO solution, then proceed in accordance with
to 1 L in a volumetric flask. Store in a polyethylene bottle.
2 3
13.2.
Determine exact concentration by the standard gravimetric
procedure. 13.3 Photometry—Proceed in accordance with 12.3.
´1
C560–88 (2005)
13.4 Calibration—Convert the photometric reading of the volumetric flasks. Add NH OH (1+1) until the brown hydrous
sample solution to micrograms of silicon by means of the precipitate of ferric hydroxide (Fe(OH) ) is just visible. Then
calibration curve. add HCl (1+1) drop-wise, while stirring, until the precipitate
just dissolves. Bring the pH of the solution to 3.0 by adding 2
14. Calculation
additional drops of HCl (1+1). Then add 2 mLof NH OH·HCl
14.1 Calculate the parts per million (ppm) of silicon in the solution.
19.2 Color Development—Heat the solutions in the flasks
original sample as follows:
almost to boiling. Add 1 mL of o-phenanthroline solution and
Silicon, ppm A 3 B /W
~ !
allow the solutions to cool. Then dilute to the mark with water.
where:
19.3 Photometry—Transfer a suitable portion of the reagent
A = silicon per 100 mL of solution found in the aliquot
blank solution to a 1-cm absorption cell, and adjust the
used, µg,
spectrophotometer to the initial setting using a wavelength of
B = aliquot factor = original volume divided by aliquot
490 nm. While maintaining this photometer adjustment, take
taken for analysis, and
the photometric readings of the calibration solutions.
W = original sample weight, g.
19.4 Calibration Curve—Plot the absorbance of the calibra-
tion solution against micrograms of iron per 100 mL of
IRON BY THE ORTHO-PHENANTHROLINE
solution.
(PHOTOMETRIC) TEST METHOD
20. Procedure
15. Summary of Test Method
20.1 Sample Solution—Proceed in accordance with 13.1.
15.1 After suitable dilution of an aliquot from the carbonate
20.2 ColorDevelopment—Proceedinaccordancewith19.2.
fusion is adjusted to a pH of 3.0, the iron is reduced with
20.3 Photometry—Proceed in accordance with 19.2.
hydroxylamine hydrochloride. The ferrous ortho-
20.4 Calibration—Convert the photometric reading of the
phenanthroline complex is formed, and its absorption is mea-
sample solution to micrograms of iron by means of the
sured at a wavelength of 490 nm.
calibration curve.
16. Stability of Color
21. Calculation
16.1 The color becomes stable within 15 min and does not
21.1 Calculate the ppm of iron in the original sample as
change for at least 48 h.
follows:
Fe, ppm A 3 B!/W
~
17. Interferences
17.1 No interfering elements are normally present in graph-
where:
ite.
A = iron per 100 mL of solution in the aliquot used, µg,
B = aliquot factor = original volume divided by aliquot
18. Reagents
taken for analysis, and
18.1 Ammonium Hydroxide (NH OH) (1+1)—Mix equal W = original sample weight, g.
volumes of concentrated NH OH, sp gr 0.90 and water.
CALCIUM BY THE PERMANGANATE
18.2 Bromine Water—Add 10 mL of bromine to 1 L of
(COLORIMETRIC) TEST METHOD
water. Allow to stand for 24 h.
18.3 Hydrochloric Acid (HCl) (1+1)—Mix equal volumes
22. Summary of Test Method
of concentrated HCl, sp gr 1.19 and water.
22.1 Calcium is precipitated as the oxalate, filtered off, and
18.4 Hydroxylamine Hydrochloride Solution—Dissolve 10
dissolved in sulfuric acid.The acid solution is added to a dilute
g of hydroxylamine hydrochloride (NH OH·HCl) in water and
potassium permanganate solution, and the decrease in absorp-
dilute to 100 mL. Discard the solution if color develops on
tion is measured at a wavelength of 528 nm.
standing for long periods of time.
18.5 Iron, Standard Solution (1 mL = 0.1 mg Fe)—Into a
23. Stability of Color
100-mLbeaker, weigh 0.1000 g of iron wire. Dissolve the wire
in 50 mLof HCl (1+1).Add 1 mLof bromine water to oxidize 23.1 Potassium permanganate solution is decomposed rap-
idly by exposure to air or light. Photometric readings should be
the iron to the ferric state. Boil the solution to expel the excess
bromine and dilute to 1 L in a volumetric flask. made at once.
18.6 Iron Wire, primary standard, over 99.9 % pure.
24. Interferences
18.7 o-Phenanthroline—Dissolve2gof 1,10-
phenanthrolineinethylalcoholanddiluteto250mLwithethyl 24.1 Ashedgraphitesamplesarenormallyfreeofsignificant
alcohol in a volumetric flask. Discard this solution if color concentrations of possible interfering ions.
develops upon long standing.
25. Reagents
19. Preparation of Calibration Curve
25.1 Ammonium Hydroxide (NH OH ) (1+6)—Mix 1 vol-
4 2
19.1 Calibration Solutions—Transfer 0.0, 1.0, 2.0, 3.0, 4.0, ume of concentrated NH OH , sp gr 0.90 with 6 volumes of
4 2
5.0, and 6.0 mLof iron solution (1 mL= 0.1 mg Fe) to 100-mL water.
´1
C560–88 (2005)
25.2 Ammonium Oxalate Solution—Prepare a saturated so- and mixed, proceed as follows: pipet a suitable aliquot (usually
lution of ammonium oxalate ((NH )
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.