ASTM D3970-80(1999)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:D3970–80(Reapproved 1999)
Standard Test Method for
Cerium in Paint Driers by Oxidimetric Determination
This standard is issued under the fixed designation D 3970; 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 5. Interferences
1.1 This test method covers the titrimetric determination of 5.1 Thistestmethodisspecificforceriuminthepresenceof
cerium in liquid cerium and rare earth paint driers and utilizes rare earth metals. Other drier metals with more than one
ferrous ammonium sulfate. valence may interfere and should be absent.
1.2 This test method is not applicable to dryer blends.
6. Reagents
1.3 This standard does not purport to address all of the
6.1 Purity of Reagents—Reagent grade chemicals shall be
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro- used in all tests. Unless otherwise indicated, it is intended that
all reagents purchased or prepared shall conform to the
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use. For a specific specifications of the Committee on Analytical Reagents of the
American Chemical Society, where such specifications are
hazard statement, see Section 7.
available . Other grades may be used, provided it is first
2. Referenced Documents
ascertained that the reagent is of sufficiently high purity to
2.1 ASTM Standards: permit its use without lessening the accuracy of the determi-
D 444 Test Methods for Chemical Analysis of Zinc Yellow nation.
Pigment (Zinc Chromate Yellow) 6.2 Purity of Water—Unless otherwise indicated, references
D 600 Specification for Liquid Paint Driers to water shall be understood to mean reagent water conforming
D 1193 Specification for Reagent Water to Type II of Specification D 1193.
E 180 Practice for Determining the Precision of ASTM 6.3 Ceric Sulfate Solution, Standard (0.1 N)—Standardized
Methods forAnalysis and Testing of Industrial Chemicals 0.1 N solutions of ceric sulfate (Ce(SO ))in1 N sulfuric acid
4 2
5 7
E 300 Practice for Sampling Industrial Chemicals may be purchased or prepared.
6.4 Ferroin Indicator (0.025 M)—Orthophenanthrolinefer-
3. Summary of Test Method 8
rous complex indicator.
3.1 The organic constituents of the liquid drier specimen are 6.5 Ferrous Ammonium Sulfate Solution, Standard (0.1
eliminated by treatment with nitric, sulfuric, and hydrochloric
M)—Standardized ferrous ammonium sulfate (FeSO ·
acids, and the cerium is converted to cerous sulfate.The cerous (NH ) SO ), 0.1 M, may be purchased or prepared in the
4 2 4
sulfate is oxidized to ceric sulfate with sodium bismuthate and
following manner. Dissolve 39.2 g of ferrous ammonium
titrated with standard ferrous ammonium sulfate.
Reagent Chemicals, American Chemical Society Specifications, American
4. Significance and Use
Chemical Society, Washington, DC. For suggestions on the testing of reagents not
4.1 This test method may be used to confirm in the presence
listed by the American Chemical Society, see Analar Standards for Laboratory
ofrareearthsthestatedceriumcontentofliquidpureceriumor Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,
rare earth driers manufactured for use in the coatings industry.
MD.
The sole source of supply of reagent grade 0.1 N solution of ceric sulfate in 1
Nsulfuricacid,knowntothecommitteeatthistimeisG.FrederickSmithCo.Ifyou
This test method is under the jurisdiction of ASTM Committee D-1 on Paint are aware of alternative suppliers, please provide this information to ASTM
and Related Coatings, Materials, andApplications and is the direct responsibility of Headquarters.Your comments will receive careful consideration at a meeting of the
Subcommittee D01.21 on Chemical Analysis of Paints and Paint Materials. responsible technical committee, which you may attend.
Current edition approved Dec. 31, 1980. Published April 1981. Thesolesourceofsupplyof0.025 Mferroinindicator,knowntothecommittee
Annual Book of ASTM Standards, Vol 06.03. at this time is G. Frederick Smith Co. If you are aware of alternative suppliers,
Annual Book of ASTM Standards, Vol 06.04. pleaseprovidethisinformationtoASTMHeadquarters.Yourcommentswillreceive
4 1
Annual Book of ASTM Standards, Vol 11.01. careful consideration at a meeting of the responsible technical committee, which
Annual Book of ASTM Standards, Vol 15.05.
you may attend.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D3970
sulfate in 250 mL of distilled water and add 20 mL of 8.3 If the sample is homogeneous keep it in a stoppered
concentrated sulfuric acid with stirring. Dilute to 1 L in a vessel to prevent solvent evaporation prior to analysis.
volumetric flask and standardize as follows:
9. Procedure
6.5.1 Pipet duplicate 20.0-mL portions of standard 0.1 N
ceric sulfate solution into 400-mL beakers and add 200-mL of
9.1 For the analysis use 1.0 g for 6 % of cerium and 2.0 g or
1.5 N sulfuric acid. Titrate with 0.1 N ferrous ammonium more for materials containing proportionally less cerium. Rare
sulfate solution as described in 9.9. Calculate the molarity, M,
earth driers are generally 45 to 50 % cerium. Thus in the
of this approximately 0.1 M solution as follows: analysis of 6 % rare earth driers, containing cerium, use 2.0 g.
Weigh the specimen from a weighing bottle or syringe by
M 5 V N/V (1)
2 1
difference, to 0.5 mg, transferring the specimen to a 250-mL
where:
Erlenmeyer flask.
V 5 ceric sulfate solution, mL,
2 9.2 Place the flask on a hot plate and warm to volatilize
N 5 normality of ceric sulfate solution, and
solvent (Note 2). Cool the flask.
V 5 ferrous am
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