ASTM D1957-86(1995)e1

Standard Test Method for Hydroxyl Value of Fatty Oils and Acids

SCOPE
1.1 This test method covers the determination of the hydroxyl content of castor oil, dehydrated castor oil, and their derivatives. This test method may also be used for other fatty products such as fatty alcohols, mono- and diglycerides, and hydroxystearic acid, but the precision will not necessarily be as indicated.  
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 whoever uses this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 6.

General Information

• Status: Historical
• Publication Date: 26-Mar-1986
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications

Relations

• Replaced By: ASTM D1957-86(2001) - Standard Test Method for Hydroxyl Value of Fatty Oils and Acids (Withdrawn 2007)
• Effective Date: 27-Mar-1986
• Referred By: ASTM E222-23 - Standard Test Methods for Hydroxyl Groups Using Acetic Anhydride Acetylation
• Effective Date: 27-Mar-1986

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
e1
Designation: D 1957 – 86 (Reapproved 1995)
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Test Method for
Hydroxyl Value of Fatty Oils and Acids
This standard is issued under the fixed designation D 1957; 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.
e NOTE—Keywords were added editorially in May 1995.
1. Scope 4.2 Condensers, straight-tube, Liebig type, having standard
ground-glass joints.
1.1 This test method covers the determination of the hy-
droxyl content of castor oil, dehydrated castor oil, and their
5. Reagents
derivatives. This test method may also be used for other fatty
5.1 Purity of Reagents—Reagent grade chemicals shall be
products such as fatty alcohols, mono- and diglycerides, and
used in all tests. Unless otherwise indicated, it is intended that
hydroxystearic acid, but the precision will not necessarily be as
all reagents shall conform to the Specifications of the Com-
indicated.
mittee on Analytical Reagents of the American Chemical
1.2 This standard does not purport to address all of the
Society, where such specifications are available. Other grades
safety concerns, if any, associated with its use. It is the
may be used provided it is first ascertained that the reagent is
responsibility of whoever uses this standard to consult and
of sufficiently high purity to permit its use without lessening
establish appropriate safety and health practices and deter-
the accuracy of the determination.
mine the applicability of regulatory limitations prior to use.
5.2 Purity of Water—Unless otherwise indicated, references
Specific hazard statements are given in Section 6.
to water shall be understood to mean reagent water conforming
2. Referenced Documents to Type I of Specification D 1193.
5.3 Acetic Anhydride,(Warning—See 6.5) fresh.
2.1 ASTM Standards:
2 5.4 n-Butyl Alcohol (Warning—See 6.1), neutralized with
D 1193 Specification for Reagent Water
0.5 N alcoholic potassium hydroxide (KOH) solution to a faint
3. Significance and Use pink phenolphthalein end point.
5.5 Ethyl Alcohol or Denatured Alcohol, conforming to
3.1 Hydroxyl value is important in establishing reactivity
Formula No. 3A or 30 of the U. S. Bureau of Alcohol, Tobacco,
with acids and isocyanates. It is also a measure of the degree of
and Firearms. Formula No. 3A is a mixture of 100 parts by
dehydration of castor oil.
volume of ethanol to 5 parts by volume of methanol. Formula
3.2 This test method determines the total amount of residual
30 is 100 parts by volume of ethanol and 10 parts by volume
hydroxyl groups present in oils and other fatty acid-containing
of methanol.
materials, reported as hydroxyl value.
5.6 Phenolphthalein Indicator Solution (10 g/L)—Dissolve
3.3 This test method involves the acetylation of hydroxyl-
1 g of phenolphthalein in methanol, ethanol, or isopropanol,
containing fatty oils and acids using pyridine as solvent. Other
and dilute to 100 mL.
groups that will react with acetic anhydride such as primary
5.7 Potassium Hydroxide, Alcoholic Solution (0.5 N)
and secondary amines under the conditions of the method will
(Warning—See 6.3)—Prepare and standardize a 0.5 N solu-
be reported as hydroxyl. The hydroxyl value is expressed as
tion of potassium hydroxide (KOH) in ethanol. The strength
milligrams of potassium hydroxide equivalent to the hydroxyl
should be not less than 0.5 N in order that the blank titrations
content of1gofthe oil. A correction is applied for acid groups
will take less than 50 mL to avoid refilling the buret.
present.
5.8 Pyridine (Warning—See 6.4), distilled at 114 to
4. Apparatus
115°C.
5.9 Pyridine-Acetic Anhydride Solution (3 + 1)—Mix 3 vol-
4.1 Erlenmeyer Flask, 250-mL, standard ground-glass-
umes of pyridine with 1 volume of acetic anhydride. Prepare
stoppered.
fresh before using.
This test method is under the jurisdiction of ASTM Committee D-1 on Paint
Reagent Chemicals, American Chemical Society Specifications, American
and Related Coatings, Materials, and Applications and is the direct responsibility of
Chemical Society, Washington, DC. For suggestions on the testing of reagents not
Subcommittee D01.32 on Drying Oils. listed by the American Chemical Society, see Analar Standards for Laboratory
Current edition approved March 27, 1986. Published May 1986. Originally Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
published as D 1957 – 61 T. Last previous edition D 1957 – 63 (1984). and National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,
Annual Book of ASTM Standards, Vol 11.01. MD.
D 1957
6. Hazards h. By this method of heating only slight, if an
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