ASTM D718-86(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: D718 − 86 (Reapproved 2020)
Standard Test Methods for
Analysis of Aluminum Silicate Pigment
This standard is issued under the fixed designation D718; 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 E11 Specification for Woven Wire Test Sieve Cloth and Test
Sieves
1.1 These test methods cover the analysis of aluminum
silicate pigment.
3. Significance and Use
1.2 The values stated in SI units are to be regarded as the
3.1 These test methods may be used to confirm the stated
standard. The values given in parentheses are for information
aluminum oxide and SiO content of aluminum silicate for
only.
quality control.
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
4. Apparatus
responsibility of the user of this standard to establish appro-
4.1 Platinum Crucible.
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
4.2 Electric furnace (or gas burner), capable of 1050 to
1.4 This international standard was developed in accor-
1100°C.
dance with internationally recognized principles on standard-
4.3 Volumetric flask, 100 and 250 mL.
ization established in the Decision on Principles for the
4.4 Colorimeter, with transmission range from 400 to 550
Development of International Standards, Guides and Recom-
nm.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
4.5 High Silica Crucible.
2. Referenced Documents
5. Purity of Reagents
2.1 ASTM Standards:
5.1 Reagent grade chemicals shall be used in all tests.
D234 Specification for Raw Linseed Oil (Withdrawn 2007)
Unless otherwise indicated, it is intended that all reagents shall
D280 Test Methods for Hygroscopic Moisture (and Other
conform to the specifications of the Committee on Analytical
Matter Volatile Under the Test Conditions) in Pigments
Reagents of the American Chemical Society, where such
D717 Test Methods for Analysis of Magnesium Silicate
specifications are available. Other grades may be used, pro-
Pigment
vided it is first ascertained that the reagent is of sufficiently
D1193 Specification for Reagent Water
high purity to permit its use without lessening the accuracy of
D1208 Test Methods for Common Properties of Certain
the determination.
Pigments
5.2 Unless otherwise indicated, references to water shall be
D2448 Test Method for Water-Soluble Salts in Pigments by
understood to mean Type II of Specification D1193.
Measuring the Specific Resistance of the Leachate of the
Pigment
SILICON DIOXIDE
6. Procedure
These test methods are under the jurisdiction of ASTM Committee D01 on
6.1 Determine the silicon dioxide content in accordance
Paint and Related Coatings, Materials, and Applications and are the direct
with Test Methods D717.
responsibility of Subcommittee D01.31 on Pigment Specifications.
Current edition approved June 1, 2020. Published June 2020. Originally
approved in 1943. Last previous edition approved in 2014 as D718 – 86 (2014).
DOI: 10.1520/D0718-86R20.
2 4
For referenced ASTM standards, visit the ASTM website, www.astm.org, or ACS Reagent Chemicals, Specifications and Procedures for Reagents and
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standard-Grade Reference Materials, American Chemical Society, Washington,
Standards volume information, refer to the standard’s Document Summary page on DC. For suggestions on the testing of reagents not listed by theAmerican Chemical
the ASTM website. Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset,
The last approved version of this historical standard is referenced on U.K., and the United States Pharmacopeia and National Formulary, U.S. Pharma-
www.astm.org. copeial Convention, Inc. (USPC), Rockville, MD.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D718 − 86 (2020)
ALUMINUM OXIDE 8. Procedure
8.1 If an appreciable residue remains after the treatment
7. Reagents
withHFinaccordancewith7.4ofTestMethodsD717,fusethe
7.1 Ammonium Acetate (20 %)—Dissolve 200 g of ammo-
residue with a small amount of K S O until it is dissolved.
2 2 7
nium acetate (NH C H O ) in 1 L of distilled water.
Leach the pyrosulfate melt out of the crucible with water and
4 2 3 2
combine the solution with the filtrate reserved in accordance
7.2 Ammonium Chloride Solution (20 g/L)—Dissolve 20 g
with 7.3 or Test Methods D717.
of ammonium chloride (NH Cl) in water and dilute to 1 L.
8.2 Bring the volume of the combined solution to 250 mL,
7.3 Ammonium Hydroxide (sp gr 0.90—Concentrated am-
and, if necessary, add HCl in order to ensure a total of 10 to 15
monium hydroxide (NH OH).
mL of HCl, add a few drops of methyl red indicator solution,
7.4 Diphenylamine Indicator Solution (1 g/100 mL)—
and heat to boiling. Add concentrated NH OH (sp gr 0.90)
Dissolve1gof diphenylamine in 100 mL of concentrated
dropwise until 1 drop changes the color of the solution to a
sulfuric acid (H SO , sp gr 1.84).
2 4
distinct yellow. Reheat the solution containing the precipitated
7.5 Hydrochloric Acid (sp gr 1.19)—Concentrated hydro-
hydroxides to boiling, boil for 1 or 2 min, and filter. Wash the
chloric acid (HCl).
precipitate once by decantation and then slightly on the filter
with hot NH Cl.
7.6 Hydrochloric Acid (1+3)—Mix 1 volume of concen-
trated HCl (sp gr 1.19) with 3 volumes of water.
8.3 Transfer the precipitate and paper to the original beaker
inwhichtheprecipitationwasmade.Dissolvetheprecipitatein
7.7 Hydrofluoric Acid (48 %)—Concentrated hydrofluoric
hot HCl (1+3), dilute to 100 mL, and precipitate again as
acid (HF).
described in 8.2. After filtering, wash the precipitate ten times
7.8 Hydrogen Peroxide (H O , 3 %, freshly prepared)—
2 2
with small portions of hot NH Cl solution. Transfer the
Mix 1 volume of H O (30 %) with 9 volumes of distilled
2 2
precipitate to a weighed platinum crucible, heat slowly until
water.
the paper is charred, and finally ignite to constant weight at
7.9 Hydroxylamine Hydrochloride (10 %)—Dissolve 10 g
1050 to 1100°C in an electric furnace or over a burner, taking
of NH OH · HCl in 100 mL of distilled water. Prepare fresh
2 care to avoid reduction. Weigh the precipitate as
weekly.
Al O +TiO +Fe O .
2 3 2 2 3
7.10 Iron Standard—Dissolve 0.1 g of analytical grade iron
8.4 Fuse the combined oxides from 8.3with9to10gof
wire in 10 mL of HCl (1+1) and dilute to 1 L. Each millilitre
K S O in a platinum crucible, starting at low temperature and
2 2 7
contains 0.1 mg of Fe.
increasing the heat gradually until the oxides have all dis-
solved. Take up the melt with 5 mLof H SO (1+1) in 150 mL
7.11 Mercuric Chloride Solution (HgCl ), saturated.
2 4
of water and warm to effect solution. Transfer the solution to a
7.12 Methyl Red Indicator Solution—Dissolve 0.2 g of
250-mL volumetric flask, dilute to volume, and mix well.
methyl red in 100 mL of methanol, ethanol, or isopropanol.
Reserve for TiO and Fe O determinations.
2 2 3
7.13 Potassium Dichromate, Standard Solution (0.05 N)—
8.5 Determine the percent of TiO as follows: Pipet an
Dissolve 2.457 g of potassium dichromate (K Cr O ) in water
2 2 7
aliquot containing 0.2 to 3.0 mg of TiO into a 100-mL
and dilute to 1 L. Standardize against National Bureau of
volumetric flask. For samples containing 0.5 to 3 % TiO,a
Standards’ standard sample No. 27b of Sibley iron ore, using
20-mL aliquot is suitable. Add 5 mL of H O (3 %), dilute to
2 2
such an amount as to give approximately the same titration as
volume with H SO (1+9) and mix well. Obtain the colorimet-
2 4
the sample to be analyzed.
ric reading in a suitable colorimeter using a filter with
7.14 Phosphoric Acid (H PO , 85 %)—Concentrated phos-
3 4
transmission limits of 400 to 450 nm or at 410
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