ASTM D1845-86(2020)

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: D1845 − 86 (Reapproved 2020)
Standard Test Methods for
Chemical Analysis of Strontium Chromate Pigment
This standard is issued under the fixed designation D1845; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope D387 Test Method for Color and Strength of Chromatic
Pigments with a Mechanical Muller
1.1 These test methods cover the chemical analysis of
D444 Test Methods for Chemical Analysis of Zinc Yellow
strontium chromate pigment.
Pigment (Zinc Chromate Yellow)
1.2 The analytical procedures appear in the following order:
D1193 Specification for Reagent Water
Sections
3. Significance and Use
Strontium by the Strontium Sulfate Method 7 to 10
3.1 These test methods may be used to confirm the stated
Chromium by the Thiosulfate Method 11 to 14
Chloride Content 15
strontium oxide and chromium oxide content of strontium
Sulfate Content 16
chromate.
Moisture and Other Volatile Matter 17
Coarse Particles 18
4. Apparatus
Mass Color and Tinting Strength 19
4.1 Gooch crucible.
1.3 This values stated in SI units are to be considered the
standard. The values given in parentheses are for information
4.2 Electric Furnace, capable of 800°C.
only.
5. Purity of Reagents
1.4 This standard does not purport to address all of the
5.1 Reagent grade chemicals shall be used in all tests.
safety concerns, if any, associated with its use. It is the
Unless otherwise indicated, it is intended that all reagents shall
responsibility of the user of this standard to establish appro-
conform to the specifications of the Committee on Analytical
priate safety, health, and environmental practices and deter-
Reagents of the American Chemical Society, where such
mine the applicability of regulatory limitations prior to use.
specifications are available. Other grades may be used, pro-
1.5 This international standard was developed in accor-
vided it is first ascertained that the reagent is of sufficiently
dance with internationally recognized principles on standard-
high purity to permit its use, without lessening the accuracy of
ization established in the Decision on Principles for the
the determination.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
5.2 Unless otherwise indicated, references to water shall be
Barriers to Trade (TBT) Committee.
understood to mean Type II of Specification D1193.
6. Preparation of Sample
2. Referenced Documents
6.1 Mix the sample thoroughly. Take a sufficient quantity
2.1 ASTM Standards:
for chemical analysis and pass it through a No. 325 (4-µm)
D185 Test Methods for Coarse Particles in Pigments
sieve.
D280 Test Methods for Hygroscopic Moisture (and Other
Matter Volatile Under the Test Conditions) in Pigments
STRONTIUM BY THE STRONTIUM SULFATE
METHOD
7. Reagents
These test methods are under the jurisdiction of ASTM Committee D01 on
Paint and Related Coatings, Materials, and Applications and are the direct
7.1 Acetic Acid (glacial).
responsibility of Subcommittee D01.31 on Pigment Specifications.
Current edition approved June 1, 2020. Published June 2020. Originally
approved in 1961. Last previous edition approved in 2014 as D1845 – 86 (2014). ACS Reagent Chemicals, Specifications and Procedures for Reagents and
DOI: 10.1520/D1845-86R20. Standard-Grade Reference Materials, American Chemical Society, Washington,
For referenced ASTM standards, visit the ASTM website, www.astm.org, or DC. For suggestions on the testing of reagents not listed by theAmerican Chemical
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset,
Standards volume information, refer to the standard’s Document Summary page on U.K., and the United States Pharmacopeia and National Formulary, U.S. Pharma-
the ASTM website. copeial Convention, Inc. (USPC), Rockville, MD.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D1845 − 86 (2020)
7.2 AmmoniumHydroxide(1+3)—Mix1volumeofconcen- CHROMIUM BY THE THIOSULFATE METHOD
trated ammonium hydroxide (NH OH, sp gr 0.90) with 3
volumes of water. 11. Reagents
11.1 Hydrochloric Acid (1+5)—Mix 1 volume of concen-
7.3 Ethyl Alcohol, conforming to Formula No. 2B or No. 30
trated hydrochloric acid (HCl, sp gr 1.19) with 5 volumes of
of the U.S. Bureau of Alcohol, Tobacco, and Firearms.
water.
7.4 Hydrochloric Acid (1+1)—Mix equal volumes of con-
11.2 PotassiumIodideSolution(150gperL)—Dissolve150
centrated hydrochloric acid (HCl, sp gr 1.19) and water.
g of potassium iodide (KI) in water and dilute to 1 L.
7.5 Sulfuric Acid (1+19)—Mix 1 volume of concentrated
11.3 Sodium Thiosulfate Standard Solution (0.1 N)—
sulfuric acid (H SO , sp gr 1.84) with 19 volumes of water.
Dissolve 24.8 g of reagent grade Na S O ·5H O in recently
2 4
2 2 3 2
boiled water and dilute to 1 L with additional recently boiled
8. Procedure water. To standardize, pipet 25 mL of the standard potassium
dichromate solution (exactly 0.1000 N) into a 250-mL Erlen-
8.1 Weigh to 0.1 mg about 0.5 g of the sample into a
meyer flask.Add 100 mL of water, 15 mL of potassium iodide
400-mLbeaker.Add 40 mLof HCl (1+1) and heat the solution
solution, and 15 mL of concentrated hydrochloric acid (sp gr
to dissolve the pigment. Add 40 mL of ethyl alcohol until the
1.19). Titrate the liberated iodine with so
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