ASTM D2024-65(1997)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Please contact ASTM International (www.astm.org) for the latest information.
Designation: D 2024 – 65 (Reapproved 1997)
Standard Test Method for
Cloud Point of Nonionic Surfactants
This standard is issued under the fixed designation D2024; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (ϵ) indicates an editorial change since the last revision or reapproval.
method is not appropriate.
1. Scope
1.1 This test method covers the determination of the solu-
4. Interferences
bility inversion temperature or “cloud point” of nonionic
4.1 Ionicsurfactantsordetergentsinconcentrationsdownto
surfactants or detergent systems which are characteristically
1 % or less of the nonionic surfactant drastically raise the
less soluble in water at higher temperatures than at lower
characteristiccloudpointofthelatter.Thepresenceofsaltsand
temperatures. It is limited to those surfactants and detergent
bases (that is, non-surface active materials) will lower the
systems for which the visible solubility change occurs over a
characteristic cloud point. Acids tend to raise the cloud point.
range of 1°C or less at concentrations of 0.5 to 1.0 % in water
between 30 and 95°C.
5. Apparatus
1.2 Chemical Limitations—Nonionic surfactants that ex-
5.1 Thermometer—AnASTMPartialImmersionThermom-
hibit a characteristic cloud point in general terms consist of a
eter having a range from−20 to+150°C or 0 to 302°F and
water-in-soluble moiety condensed with 50 to 75 % by weight
conforming to the requirements for Thermometer 1C or 1F in
of ethylene oxide.
accordance with Specification E1E1.
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
6. Procedure
responsibility of the user of this standard to establish appro-
6.1 Prepare a 1.0 % test solution by weighing a 16 0.1-g
priate safety and health practices and determine the applica-
sample into a 150-mL beaker and add 100 mL of distilled or
bility of regulatory limitations prior to use.
demineralized water which is at a temperature of less than
30°C.Agitateuntilthesampleisdissolved.Pour5065mLof
2. Referenced Documents
test solution into a 25 by 200-mm test tube of borosilicate
2.1 ASTM Standards:
glass. While agitating the test solution slowly with the ther-
E1 Specification for ASTM Thermometers
mometer, heat the test tube with a bunsen burner until the test
solution becomes definitely cloudy. Remove from heat. While
3. Significance and Use
stirring slowly with the thermometer, allow the test solution to
3.1 The cloud point temperature is a reproducible charac-
cool slowly until it becomes clear. Record the temperature
teristic of certain pur
...