ASTM D6647-18

Standard Test Method for Determination of Acid Soluble Iron via Atomic Absorption

SIGNIFICANCE AND USE
5.1 In certain applications, such as acid purification, acidic food or chemical purification or decolorization, or other applications wherein iron may be leached out of the carbon, the use of acid-washed carbons will reduce or eliminate color pickup in the effluent or in the product. The acid soluble iron content is usually specified by the carbon supplier to prevent unacceptable levels of iron leach occurring.  
5.2 Detection limits, sensitivity, and optimum ranges will vary with the models of atomic absorption spectrophotometers. General instrumental parameters are as follows:  
5.2.1 Iron hollow cathode lamp.  
5.2.2 Wavelength: 248.3 nm.  
5.2.3 Fuel: acetylene (high purity).  
5.2.4 Oxidant: air (from compressed air line, laboratory compressor, or a cylinder of compressed air—all need to be clean and dry).  
5.2.5 Type of flame: oxidizing.  
5.2.6 The following lines may also be used:    
248.8 nm Relative Sensitivity 2  
271.9 nm Relative Sensitivity 4  
302.1 nm Relative Sensitivity 5  
252.7 nm Relative Sensitivity 6  
372.0 nm Relative Sensitivity 10  
5.3 The method, as written, is intended for carbons having an acid soluble iron content of 0.0030 to 0.050 %. For carbons having higher iron contents, larger dilutions or smaller aliquots may be used.  
5.4 The user should validate that there are no interferences from other metals in the sample matrix.  
5.5 To prevent erroneous results, the user should ensure that no iron instruments contact any of the sample or the solutions used in this procedure. Only glass, ceramics, or plastic should be allowed to contact the sample or solutions.
SCOPE
1.1 This test method covers the determination of the acid soluble iron content of granular and powdered activated carbons, using an atomic absorption spectroscopy method by direct aspiration. Hydrochloric acid is used to extract the iron. This test method is not directly usable to determine the total iron concentration of a sample.  
1.2 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. For a specific hazard statement, see Section 8.  
1.3 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.

General Information

• Status: Published
• Publication Date: 30-Apr-2018
• ICS: 19.020 - Test conditions and procedures in general
• ICS: 71.040.50 - Physicochemical methods of analysis
• Technical Committee: D28 - Activated Carbon
• Drafting Committee: D28.02 - Liquid Phase Evaluation

Relations

• Replaces: ASTM D6647-01(2011) - Standard Test Method for Determination of Acid Soluble Iron Via Atomic Absorption
• Effective Date: 01-May-2018
• Refers: ASTM E287-02(2019) - Standard Specification for Laboratory Glass Graduated Burets
• Effective Date: 01-Jul-2019
• Refers: ASTM E288-10(2017) - Standard Specification for Laboratory Glass Volumetric Flasks
• Effective Date: 01-Nov-2017
• Refers: ASTM E177-14 - Standard Practice for Use of the Terms Precision and Bias in ASTM Test Methods
• Effective Date: 01-May-2014
• Refers: ASTM E11-13 - Standard Specification for Woven Wire Test Sieve Cloth and Test Sieves
• Effective Date: 01-Oct-2013
• Refers: ASTM E691-13 - Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
• Effective Date: 01-May-2013
• Refers: ASTM E177-13 - Standard Practice for Use of the Terms Precision and Bias in ASTM Test Methods
• Effective Date: 01-May-2013
• Refers: ASTM E287-02(2012) - Standard Specification for Laboratory Glass Graduated Burets
• Effective Date: 01-Nov-2012
• Refers: ASTM E691-11 - Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
• Effective Date: 01-Nov-2011
• Refers: ASTM D2652-11 - Standard Terminology Relating to Activated Carbon
• Effective Date: 15-Jun-2011
• Refers: ASTM E177-10 - Standard Practice for Use of the Terms Precision and Bias in ASTM Test Methods
• Effective Date: 01-Oct-2010
• Refers: ASTM E288-10 - Standard Specification for Laboratory Glass Volumetric Flasks
• Effective Date: 01-Apr-2010
• Refers: ASTM E11-09e1 - Standard Specification for Woven Wire Test Sieve Cloth and Test Sieves
• Effective Date: 01-May-2009
• Refers: ASTM E177-08 - Standard Practice for Use of the Terms Precision and Bias in ASTM Test Methods
• Effective Date: 01-Oct-2008
• Refers: ASTM E691-08 - Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
• Effective Date: 01-Oct-2008

Overview

ASTM D6647-18 is a globally recognized standard developed by ASTM International for the determination of acid soluble iron in granular and powdered activated carbons, utilizing atomic absorption spectroscopy (AAS) via direct aspiration. This test method is not intended to determine total iron content but is specifically designed to assess the iron that is extractable by hydrochloric acid from activated carbon materials. Ensuring low acid soluble iron content in activated carbons is essential in sensitive applications, such as acid purification and chemical processes, to prevent unwanted iron leaching that can cause color contamination or impact product quality.

Key Topics

• Purpose of the Standard
  ASTM D6647-18 offers precise instructions for measuring acid soluble iron levels in activated carbon. This information helps suppliers and users confirm quality, especially where the presence of iron is strictly controlled.

• Test Principles

  • Hydrochloric acid is used to extract soluble iron from a ground, oven-dried carbon sample.
  • Atomic absorption spectroscopy (AAS) quantitatively measures the iron content in the filtrate.
  • The method covers acid soluble iron content in the range of 0.0030% to 0.050% for activated carbons. For higher concentrations, further dilution or smaller sample aliquots are recommended.
  • Users must take precautions to prevent contamination, notably by avoiding contact with iron-containing equipment.

• Instrument and Chemical Requirements

  • Suitable AAS instrumentation, including an iron hollow cathode lamp and oxidizing flame.
  • High purity reagents specifically conforming to relevant ASTM specifications, such as hydrochloric acid and Type II reagent water.

• Accuracy, Precision, and Interferences

  • The standard underlines the importance of instrument calibration, matrix interference validation, and correct handling to achieve accurate and reproducible results.
  • Laboratories are advised to follow prescribed procedures for sample preparation, calibration, and calculation for reliable analysis.

Applications

ASTM D6647-18 is widely applied in sectors where activated carbons are used and iron contamination must be minimized:

• Acid Purification: Ensures that activated carbon does not release excessive iron into acids, maintaining product clarity and purity.
• Food and Beverage Industry: Acid-washed carbon with low soluble iron prevents iron leaching, which can cause discoloration and affect taste.
• Chemical Processing: Guarantees consistent performance of activated carbons in purification and decolorization processes.
• Activated Carbon Manufacturing: Used as a quality control reference by carbon producers to certify that their materials meet client specifications for acid soluble iron.
• Water Treatment: Helps operators select carbons that do not introduce additional iron, supporting regulatory compliance.

Implementing ASTM D6647-18 ensures consistent product quality, regulatory adherence, and optimal performance in applications sensitive to iron contamination.

Related Standards

For a comprehensive quality assurance program and laboratory compliance, the following referenced standards are often used in conjunction with ASTM D6647-18:

• ASTM D1193 – Specification for Reagent Water
• ASTM D2652 – Terminology Relating to Activated Carbon
• ASTM E11 – Specification for Woven Wire Test Sieve Cloth and Test Sieves
• ASTM E177 – Practice for Use of Terms Precision and Bias in ASTM Test Methods
• ASTM E287 – Specification for Laboratory Glass Graduated Burets
• ASTM E288 – Specification for Laboratory Glass Volumetric Flasks
• ASTM E300 – Practice for Sampling Industrial Chemicals
• ASTM E691 – Practice for Conducting Interlaboratory Studies to Determine Test Method Precision

Utilizing ASTM D6647-18 alongside these standards enhances laboratory proficiency and ensures reliable and valid analytical outcomes when assessing acid soluble iron in activated carbons.

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: D6647 − 18
Standard Test Method for
Determination of Acid Soluble Iron via Atomic Absorption
This standard is issued under the fixed designation D6647; 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 2.2 NIST Publication:
Circular 602 Testing of Glass Volumetric Apparatus
1.1 This test method covers the determination of the acid
soluble iron content of granular and powdered activated
3. Terminology
carbons, using an atomic absorption spectroscopy method by
3.1 Definitions—Terms relating to this standard are defined
direct aspiration. Hydrochloric acid is used to extract the iron.
in Terminology D2652.
This test method is not directly usable to determine the total
3.1.1 atomic absorption—in flame atomic absorption
iron concentration of a sample.
spectrometry, a sample is aspirated into a flame and atomized.
1.2 This standard does not purport to address all of the
A light beam is directed through the flame, into a
safety concerns, if any, associated with its use. It is the
monochromator, and onto a detector that measures the amount
responsibility of the user of this standard to establish appro-
of light absorbed by the atomized element in the flame.
priate safety, health, and environmental practices and deter-
Because each metal has its own characteristic absorption
mine the applicability of regulatory limitations prior to use.
wavelength, a source lamp of that element is used.The amount
For a specific hazard statement, see Section 8.
of energy at the characteristic wavelength absorbed in the
1.3 This international standard was developed in accor-
flame is proportional to the concentration of the element in the
dance with internationally recognized principles on standard-
sample over a limited concentration range.
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom- 4. Summary of Test Method
mendations issued by the World Trade Organization Technical
4.1 Arepresentativesampleofthematerialtobeanalyzedis
Barriers to Trade (TBT) Committee.
collected according to Practice E300. A known weight of the
sample is ground until 95 % or more of the sample passes 325
2. Referenced Documents
mesh. The ground sample is oven dried, and then mixed with
2.1 ASTM Standards: a dilute hydrochloric acid. The solution is boiled for 5 min to
D1193 Specification for Reagent Water convert the iron into a soluble chloride, and then cooled and
D2652 Terminology Relating to Activated Carbon filtered. The filter cake is washed with water. Then the filtrate
E11 Specification for Woven Wire Test Sieve Cloth and Test is transferred quantitatively to a beaker. The concentration of
Sieves iron in the filtrate is measured by atomic absorption against a
E177 Practice for Use of the Terms Precision and Bias in set of standards. The acid soluble iron concentration is then
ASTM Test Methods calculated against the weight of the original sample.
E287 Specification for Laboratory Glass Graduated Burets
5. Significance and Use
E288 Specification for Laboratory Glass Volumetric Flasks
E300 Practice for Sampling Industrial Chemicals 5.1 In certain applications, such as acid purification, acidic
E691 Practice for Conducting an Interlaboratory Study to food or chemical purification or decolorization, or other
Determine the Precision of a Test Method applicationswhereinironmaybeleachedoutofthecarbon,the
use of acid-washed carbons will reduce or eliminate color
pickup in the effluent or in the product. The acid soluble iron
content is usually specified by the carbon supplier to prevent
This test method is under the jurisdiction of ASTM Committee D28 on
unacceptable levels of iron leach occurring.
ActivatedCarbonandisthedirectresponsibilityofSubcommitteeD28.02onLiquid
Phase Evaluation.
5.2 Detection limits, sensitivity, and optimum ranges will
CurrenteditionapprovedMay1,2018.PublishedJune2018Originallyapproved
vary with the models of atomic absorption spectrophotometers.
in 2001. Last previous edition approved in 2011 as D6647 – 01 (2011). DOI:
10.1520/D6647-18.
General instrumental parameters are as follows:
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 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
D6647 − 18
5.2.1 Iron hollow cathode lamp. sufficiently high purity to permit its use without lessening the
5.2.2 Wavelength: 248.3 nm. accuracy of the determination.
5.2.3 Fuel: acetylene (high purity).
7.2 Purity of Water—References to water shall be under-
5.2.4 Oxidant: air (from compressed air line, laboratory
stood to mean reagent water conforming to Specification
compressor, or a cylinder of compressed air—all need to be
D1193 for Type II reagent water.
clean and dry).
7.3 Standard Iron Solution I—Completely dissolve 0.1000 g
5.2.5 Type of flame: oxidizing.
of iron wire, C.P., in 20 mL of hydrochloric acid, concentrated
5.2.6 The following lines may also be used:
ACS hydrochloric acid grade, and 50 mL of water. Allow to
248.8 nm Relative Sensitivity 2
stand overnight. Quantitatively transfer the solution into a 1-L
271.9 nm Relative Sensitivity 4
302.1 nm Relative Sensitivity 5
volumetric flask and dilute to the mark with water. Mix
252.7 nm Relative Sensitivity 6
thoroughly. This solution contains 0.1 mg of iron per mL.
372.0 nm Relative Sensitivity 10
7.4 Standard Iron Solution II—Pipette 100.0 mLof standard
5.3 The method, as written, is intended for carbons having
iron solution I into a 1-L volumetric flask. Dilute to the mark
an acid soluble iron content of 0.0030 to 0.050 %. For carbons
with water. Mix thoroughly. This solution contains 0.01 mg of
having higher iron contents, larger dilutions or smaller aliquots
iron/mL.
may be used.
NOTE 2—Commercially available iron solutions obtained from chemi-
5.4 The user should validate that there are no interferences
calsupplyhouseshavebeenfoundtobeacceptable,providedtheaccuracy
from other metals in the sample matrix.
of the solution meets specified requirements.
5.5 To prevent erroneous results, the user should ensure that
8. Hazards
no iron instruments contact any of the sample or the solutions
used in this procedure. Only glass, ceramics, or plastic should
8.1 Severalpotentialhazardsareassociatedwithconducting
be allowed to contact the sample or solutions.
this test procedure. It is not the purpose of this standard to
address all potential health and safety hazards associated with
6. Apparatus
its use. The user is responsible for establishing appropriate
6.1 Atomic Absorption Spectrometer, consisting of a light health and safety practices and determining the applicability of
source emitting the line spectrum of an element (see 5.2.1), a any federal and state regulations before attempting to use this
device for vaporizing the sample (usually a flame), a means for test method.
isolating an absorption line (monochromator or filter and 8.1.1 Since this procedure involves the use of hydrochloric
adjustable slit—see 5.2.2 and 5.2.6), and a photoelectric
acid, all necessary personal protective equipment for handling
detector with its associated electronic amplifying and measur- acids should be used, including rubber gloves, lab apron, and
ing equipment.
goggles. Careful handling and good laboratory technique
should always be used when working with chemicals. Avoid
6.2 Beakers—Griffen, low form, 400 mL, Pyrex or equiva-
contact with hydrochloric acid or acid vapor. Care should be
lent.
taken to prevent burns during handling of various solutions
6.3 Cylinder—ASTM, graduated, 100 mL.
during this test procedure.
6.4 Flask—Filtering, with side tube, 250 mL. 8.1.2 The atomic absorption spectrometer should be vented
appropriately, as recommended by the instrument
6.5 Buchner Funnel—Size D, 71-mm ID.
manufacturer, to dissipate fumes and vapors generated by the
6.6 Filter Paper—Whatman No. 3, 7.0 cm or equivalent.
combustion the flame. This precaution protects laboratory
personnel from toxic vapors, protects the instrument from
6.7 Flasks—Volumetric, 50, 100, 250, 500, and 1000 mL.
corrosive vapors, and prevents flame stability from being
6.8 Pipettes—Volumetric, 1, 2, 5, 10, 25, and 100 mL.
affected by room drafts.
6.9 325-Mesh Screen (U.S. Sieve series).
8.1.3 The user of this test should comply with all federal,
state, and local regulations for safe disposal of all samples and
6.10 Analytical Balance, accuracy 60.0001 g.
reagents used.
6.11 Hotplate.
NOTE 1—All volumetric measuring equipment should meet or exceed 9. Sampling
the requirements of NIST Circular 602. Volumetric glassware meeting
9.1 Collect a representative sample of the carbon to be
those specifications is normally designated as “Class A.” See also
tested using Practice E300. Approximately 10 g of the repre-
Specifications E287 and E288.
sentative sample will be needed for this test.
7. Reagents
10. Procedure
7.1 Purity of Reagents—Reagent-grade chemicals shall be
used in all tests. Unless otherwise indicated, it is intended that 10.1 Calibration Standards:
all reagents shall conform to the specifications of the Commit- 10.1.1 For those instruments which do not read out directly
tee onAnalytical Reagents of
...

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: D6647 − 01 (Reapproved 2011) D6647 − 18
Standard Test Method for
Determination of Acid Soluble Iron Viavia Atomic
Absorption
This standard is issued under the fixed designation D6647; 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 This test method covers the determination of the acid soluble iron content of granular and powdered activated carbons, using
an atomic absorption spectroscopy method by direct aspiration. Hydrochloric acid is used to extract the iron. This test method is
not directly usable to determine the total iron concentration of a sample.
1.2 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. For a specific hazard statement, see Section 8.
1.3 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:
D1193 Specification for Reagent Water
D2652 Terminology Relating to Activated Carbon
D1193 Specification for Reagent Water
E11 Specification for Woven Wire Test Sieve Cloth and Test Sieves
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
E287 Specification for Laboratory Glass Graduated Burets
E288 Specification for Laboratory Glass Volumetric Flasks
E300 Practice for Sampling Industrial Chemicals
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
2.2 NIST Publication:
Circular 602 Testing of Glass Volumetric Apparatus
3. Terminology
3.1 Definitions—Terms relating to this standard are defined in Terminology D2652.
3.1.1 atomic absorption—in flame atomic absorption spectrometry, a sample is aspirated into a flame and atomized. A light
beam is directed through the flame, into a monochromator, and onto a detector that measures the amount of light absorbed by the
atomized element in the flame. Because each metal has its own characteristic absorption wavelength, a source lamp of that element
is used. The amount of energy at the characteristic wavelength absorbed in the flame is proportional to the concentration of the
element in the sample over a limited concentration range.
4. Summary of Test Method
4.1 A representative sample of the material to be analyzed is collected according to Practice E300. A known weight of the
sample is ground until 95 % or more of the sample passes 325 mesh. The ground sample is oven dried, and then mixed with a dilute
This test method is under the jurisdiction of ASTM Committee D28 on Activated Carbon and is the direct responsibility of Subcommittee D28.02 on Liquid Phase
Evaluation.
Current edition approved Sept. 1, 2011May 1, 2018. Published November 2011June 2018 Originally approved in 2001. Last previous edition approved in 20062011 as
D6647 – 01 (2011).(2006). DOI: 10.1520/D6647-01R11.10.1520/D6647-18.
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.
Available from National Institute of Standards and Technology (NIST), 100 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
D6647 − 18
hydrochloric acid. The solution is boiled for 5 minutesmin to convert the iron into a soluble chloride, and then cooled and filtered.
The filter cake is washed with water. Then the filtrate is transferred quantitatively to a beaker. The concentration of iron in the
filtrate is measured by atomic absorption against a set of standards. The acid soluble iron concentration is then calculated against
the weight of the original sample.
5. Significance and Use
5.1 In certain applications, such as acid purification, acidic food or chemical purification or decolorization, or other applications
wherein iron may be leached out of the carbon, the use of acid-washed carbons will reduce or eliminate color pickup in the effluent
or in the product. The acid soluble iron content is usually specified by the carbon supplier to prevent unacceptable levels of iron
leach occurring.
5.2 Detection limits, sensitivity, and optimum ranges will vary with the models of atomic absorption spectrophotometers.
General instrumental parameters are as follows:
5.2.1 Iron hollow cathode lamp.
5.2.2 Wavelength: 248.3 nm.
5.2.3 Fuel: acetylene (high purity).
5.2.4 Oxidant: air (from compressed air line, laboratory compressor, or a cylinder of compressed air—all need to be clean and
dry).
5.2.5 Type of flame: oxidizing.
5.2.6 The following lines may also be used:
248.8 nm Relative Sensitivity 2
271.9 nm Relative Sensitivity 4
302.1 nm Relative Sensitivity 5
252.7 nm Relative Sensitivity 6
372.0 nm Relative Sensitivity 10
5.3 The method, as written, is intended for carbons having an acid soluble iron content of 0.0030 to 0.050 %0.050 %. For
carbons having higher iron contents, larger dilutions or smaller aliquots may be used.
5.4 The user should validate that there are no interferences from other metals in the sample matrix.
5.5 To prevent erroneous results, the user should ensure that no iron instruments contact any of the sample or the solutions used
in this procedure. Only glass, ceramics, or plastic should be allowed to contact the sample or solutions.
6. Apparatus
6.1 Atomic absorption spectrometer , Absorption Spectrometer, consisting of a light source emitting the line spectrum of an
element (see 5.2.1 above), ), a device for vaporizing the sample (usually a flame), a means for isolating an absorption line
(monochromator or filter and adjustable slit—see 5.2.2 and 5.2.6 above), ), and a photoelectric detector with its associated
electronic amplifying and measuring equipment.
6.2 Beakers—Griffen, low form, 400 ml.,mL, Pyrex or equivalent.
6.3 Cylinder—ASTM, graduated, 100 ml.mL.
6.4 Flask—Filtering, with side tube, 250 ml.mL.
6.5 Buchner Funnel—Size D, 71 mm. 71-mm ID.
6.6 Filter Paper—Whatman No. 3, 7.0 cm.cm or equivalent.
6.7 Flasks—Volumetric, 50, 100.100, 250, 500, and 1000 ml.mL.
6.8 Pipettes—Volumetric, 1,2,5,10,25, 1, 2, 5, 10, 25, and 100 ml.mL.
6.9 325 Mesh 325-Mesh Screen (U.S. Sieve series).
6.10 Analytical Balance, accuracy plus or minus 0.0001 60.0001 g.
6.11 Hot Plate. Hotplate.
NOTE 1—All volumetric measuring equipment should meet or exceed the requirements of NIST Circular 602. Volumetric glassware meeting those
specifications is normally designated as “Class A”.A.” See also specificationsSpecifications E287 and E288.
7. Reagents
7.1 Purity of Reagents—Reagent grade Reagent-grade chemicals shall be used in all tests. Unless otherwise indicated, it is
intended that all reagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical
Society, where such specifications are available. Other grades may be used, provided it is first ascertained that the reagent is of
sufficiently high purity to permit its use without lessening the accuracy of the determination.
D6647 − 18
7.2 Purity of Water—References to water shall be understood to mean reagent water conforming to specificationSpecification
D1193 for Type II reagent water.
7.3 Standard Iron Solution I—Completely dissolve 0.1000 grams 0.1000 g of iron wire, C.P., in 20 ml.mL of hydrochloric acid,
concentrated ACS hydrochloric acid grade, and 50 ml.mL of water. Allow to stand overnight. Quantitatively transfer the solution
into a one liter 1-L volumetric flask and dilute to the mark with water. Mix thoroughly. This solution contains 0.1 mg.mg of iron
per ml.mL.
7.4 Standard Iron Solution II—Pipette 100.0 ml.mL of standard iron solution I into a one liter 1-L volumetric flask. Dilute to
the mark with water. Mix thoroughly. This solution contains 0.01 mg.mg of iron/ml.iron/mL.
NOTE 2—Commercially available iron solutions obtained from chemical supply houses have been found to be acceptable, provided the accuracy of the
solution meets specified requirements.
8. Hazards
8.1 Several potential hazards are associated with conducting this test procedure. It is not the purpose of this standard to address
all potential health and safety hazards associated with its use. The user is responsible for establishing appropriate health and safety
practices and to determine determining the applicability of any federal and state regulations before attempting to use this test
method.
8.1.1 Since this procedure involves the use of hydrochloric acid, all necessary personal protective equipment for handling acids
should be used, including rubber gloves, lab apron, and goggles. Careful handling and good laboratory technique should always
be used when working with chemicals. Avoid contact with hydrochloric acid or acid vapor. Care should be taken to prevent burns
during handling of various solutions during this test procedure.
8.1.2 The atomic absorption spectrometer should be vented appropriately, as recommended by the instrument manufacturer, to
dissipate fumes and vapors generated by the combustion the flame. This precaution protects laboratory personnel from toxic
vapors, protects the instrument from corrosive vapors, and prevents flame stability from being affected by room drafts.
8.1.3 The user of this test should comply with all federal, state, and local regulations for safe disposal of all samples and
reagents used.
9. Sampling
9.1 Collect a representative sample of the carbon to be tested using Standard Practice E300. Approximately 10 gramsg of if the
representative sample will be neede
...