ASTM D4607-94(1999)
(Test Method)Standard Test Method for Determination of Iodine Number of Activated Carbon
Standard Test Method for Determination of Iodine Number of Activated Carbon
SCOPE
1.1 This test method covers the determination of the relative activation level of unused or reactivated carbons by adsorption of iodine from aqueous solution. The amount of iodine absorbed (in milligrams) by 1 g of carbon using test conditions listed herein is called the iodine number.
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 and health practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 7.
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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
Designation:D 4607 – 94 (Reapproved 1999)
Standard Test Method for
Determination of Iodine Number of Activated Carbon
This standard is issued under the fixed designation D 4607; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope Circular 602—Testing of Glass Volumetric Apparatus
1.1 Thistestmethodcoversthedeterminationoftherelative
3. Summary of Test Method
activation level of unused or reactivated carbons by adsorption
3.1 This test method is based upon a three-point adsorption
of iodine from aqueous solution. The amount of iodine
isotherm (see Practices D 3860). A standard iodine solution is
absorbed (in milligrams) by1gof carbon using test conditions
treated with three different weights of activated carbon under
listed herein is called the iodine number.
specifiedconditions.Thecarbontreatedsolutionsarefilteredto
1.2 This standard does not purport to address all of the
separate the carbon from the treated iodine solution (filtrate).
safety concerns, if any, associated with its use. It is the
Iodine remaining in the filtrate is measured by titration. The
responsibility of the user of this standard to establish appro-
amount of iodine removed per gram of carbon is determined
priate safety and health practices and determine the applica-
for each carbon dosage and the resulting data used to plot an
bility of regulatory limitations prior to use. Specific hazard
adsorption isotherm. The amount of iodine adsorbed (in
statements are given in Section 7.
milligrams) per gram of carbon at a residual iodine concentra-
2. Referenced Documents tion of 0.02 N is reported as the iodine number.
3.2 Iodine concentration in the standard solution affects the
2.1 ASTM Standards:
capacity of an activated carbon for iodine adsorption. There-
C 819 Test Method for Specific Surface Area of Carbon or
fore, the normality of the standard iodine solution must be
Graphite
maintained at a constant value (0.100 6 0.001N) for all iodine
D 1193 Specification for Reagent Water
number measurements.
D 2652 Terminology Relating to Activated Carbon
3.3 The apparatus required consists of various laboratory
D 2867 Test Method for Moisture in Activated Carbon
glasswareusedtopreparesolutionsandcontactcarbonwiththe
D 3860 Practices for Determination ofAdsorptive Capacity
4 standard iodine solution. Filtration and titration equipment are
of Carbon by Isotherm Technique
also required.
E 11 Specification for Wire-Cloth Sieves for Testing Pur-
poses
4. Significance and Use
E 177 Practice for Use of the Terms Precision and Bias in
5 4.1 The iodine number is a relative indicator of porosity in
ASTM Test Methods
5 an activated carbon. It does not necessarily provide a measure
E 287 SpecificationforLaboratoryGlassGraduatedBurets
of the carbon’s ability to absorb other species. Iodine number
E 288 Specification for Laboratory Glass Volumetric
5 may be used as an approximation of surface area for some
Flasks
6 types of activated carbons (see Test Method C 819). However,
E 300 Practice for Sampling Industrial Chemicals
it must be realized that any relationship between surface area
2.2 NIST Publication:
and iodine number cannot be generalized. It varies with
changes in carbon raw material, processing conditions, and
This test method is under the jurisdiction of ASTM Committee D-28 on pore volume distribution (see Definitions D 2652).
ActivatedCarbonandisthedirectresponsibilityofSubcommitteeD28.02onLiquid
4.2 The presence of adsorbed volatiles, sulfur; and water
Phase Evaluation.
extractables may affect the measured iodine number of an
Current edition approved Nov. 15, 1994. Published January 1995. Originally
activated carbon.
published as D 4607 – 86. Last previous edition D 4607 – 86 (1990).
Discontinued—See 1986 Annual Book of ASTM Standards, Vol 15.01.
Annual Book of ASTM Standards, Vol 11.01.
Annual Book of ASTM Standards, Vol 15.01.
5 7
Annual Book of ASTM Standards, Vol 14.02. Available from National Institute of Standards and Technology, U.S. Depart-
Annual Book of ASTM Standards, Vol 15.05. ment of Commerce, Gaithersburg, MD 20899.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D 4607
5. Apparatus ated with the chemicals used in this procedure. The “Material
Safety Data Sheet” (MSDS) for each reagent listed in Section
NOTE 1—All volumetric measuring equipment should meet or exceed
6 should be read and understood. Special precautions to be
the requirements of NIST Circular 602. Volumetric glassware meeting
taken during use of each reagent are included on the “Material
these specifications is generally designated as “Class A”. See also
Safety Data Sheet” (MSDS). First aid procedures for contact
Specifications E 287 and E 288.
with a chemical are also listed on its “MSDS.” A “Material
5.1 Analytical Balance, accuracy 60.0001 g.
Safety Data Sheet” for each reagent may be obtained from the
5.2 Buret, 10-mL capacity or 5-mL precision buret.
manufacturer. Other safety and health hazard information on
5.3 Flasks, Erlenmeyer 250-mL capacity with ground glass
9,10 ,11
reagents used in this procedure is available.
stoppers.
7.3 Careful handling and good laboratory technique should
5.4 Flask, Erlenmeyer wide-mouthed, 250-mL capacity.
always be used when working with chemicals. Avoid contact
5.5 Beakers, assorted sizes.
with hydrochloric acid or acid vapor. Care should also be taken
5.6 Bottles, amber, for storage of iodine and thiosulfate
to prevent burns during heating of various solutions during this
solutions.
test procedure.
5.7 Funnels, 100-mm top inside diameter.
7.4 The user of this test method should comply with federal,
5.8 Filter Paper, 18.5-cm prefolded paper, Whatman No.
state, and local regulations for safe disposal of all samples and
2V or equivalent.
reagents used.
5.9 Pipets, volumetric type, 5.0, 10.0, 25.0, 50.0, and
100.0-mL capacity.
8. Preparation of Solutions
5.10 Volumetric Flasks,1L.
8.1 Hydrochloric Acid Solution (5 % by weight)—Add 70
5.11 Graduated Cylinders, 100 mL and 500 mL.
mL of concentrated hydrochloric acid to 550 mL of distilled
water and mix well. A graduated cylinder may be used for
6. Reagents
measurement of volume.
6.1 Purity of Reagents—Reagent grade chemicals shall be
8.2 Sodium Thiosulfate (0.100 N)—Dissolve 24.820 g of
used in all tests. Unless otherwise indicated, it is intended that
sodium thiosulfate in approximately 75 6 25 mL of freshly
all reagents shall conform to the specifications of the Commit-
boiled distilled water.Add 0.10 6 0.01 g of sodium carbonate
tee onAnalytical Reagents of theAmerican Chemical Society,
tominimizebacterialdecompositionofthethiosulfatesolution.
where such specifications are available. Other grades may be
Quantitatively transfer the mixture to a 1-L volumetric flask
used, provided it is first ascertained that the reagent is of
and dilute to the mark. Allow the solution to stand at least 4
sufficiently high purity to permit its use without lessening the
days before standardizing. The solution should be stored in an
accuracy of the determination.
amber bottle.
6.2 Purity of Water—References to water shall be under-
8.3 Standard Iodine Solution (0.100 6 0.001 N)—Weigh
stood to mean reagent water conforming to Specification
12.700 g of iodine and 19.100 g of potassium iodide (KI) into
D 1193 for Type II reagent water.
a beaker. Mix the dry iodine and potassium iodide.Add 2 to 5
6.3 Hydrochloric Acid, concentrated.
mLof water to the beaker and stir well. Continue adding small
6.4 Sodium Thiosulfate, (Na S O·5H O).
2 2 3 2
increments of water (approximately 5 mL each) while stirring
6.5 Iodine, United States Pharmacopeia, resublimed crys-
until the total volume is 50 to 60 mL. Allow the solution to
tals.
stand a minimum of4hto ensure that all crystals are
6.6 Potassium Iodide.
thoroughly dissolved. Occasional stirring during this 4-h pe-
6.7 Potassium Iodate, primary standard.
riod will aid in the dissolution. Quantitatively transfer to a 1-L
6.8 Starch, soluble potato or arrowroot.
volumetric flask and fill to the mark with distilled water. It is
6.9 Sodium Carbonate.
important that the standard iodine solution has an iodide-to-
iodine weight ratio of 1.5 to 1. Store the solution in an amber
7. Hazards
bottle.
7.1 Severalpotentialhazardsareassociatedwithconducting
8.4 Potassium Iodate Solution (0.1000 N)—Dry 4 or more
this test procedure. It is not the purpose of this standard to
grams of primary standard grade potassium iodate (KIO)at
address all potential health and safety hazards encountered
110 65°Cfor2handcooltoroomtemperatureinadesiccator.
with its use. The user is responsible for establishing appropri-
Dissolve 3.5667 6 0.1 mg of the dry potassium iodate in about
ate health and safety practices before use of this test procedure.
100 mL of distilled water. Quantitatively transfer to a 1-L
Determine the applicability of federal and state regulations
volumetric flask and fill to the mark with distilled water. Mix
before attempting to use this test method.
thoroughly and store in a glass-stoppered bottle.
7.2 Personnel conducting the iodine number procedure
should be aware of potential safety and health hazards associ-
The “Chemical Safety Data Sheet” for the subject chemical is available from
the Manufacturing Chemists Association, Washington, DC.
8 10
“Reagent Chemicals,American Chemical Society Specifications,”Am. Chemi- Sax, N. I., Dangerous Properties of Industrial Materials, 4th edition, 1975,
cal Soc., Washington, DC. For suggestions on the testing of reagents not listed by Van Nostrand Reinhold Company, New York, NY.
theAmerican Chemical Society, see “Reagent Chemicals and Standards,” by Joseph NIOSH/OSHA Pocket Guide to Chemical Haz
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.