ASTM D2024-09

Standard Test Method for Cloud Point of Nonionic Surfactants

SIGNIFICANCE AND USE
The cloud point temperature is a reproducible characteristic of certain  pure  nonionic surfactants. It is also characteristic of certain nonionic surfactant formulated systems. This test method is appropriate for both systems.
Note 1—If the transition from a distinctly cloudy to a clear solution is not sharp, that is, if it does not take place within a range of 1°C, this test method is not appropriate.
SCOPE
1.1 This test method covers a procedure to determine the “cloud point” of nonionic surfactants or detergent systems. Cloud Point is the temperature at which dissolved components (solids or liquids) are no longer completely soluble, precipating as a second phase giving the fluid a cloudy appearance. It is limited to those surfactants and detergent systems for which the visible solubility change occurs over a range of 1°C or less at concentrations of 0.5 to 1.0 % in DI water between 30 and 95°C.
1.2 Chemical Limitations—Nonionic surfactants that exhibit a characteristic cloud point in general terms consist of a water-in-soluble moiety condensed with 50 to 75 % by weight of ethylene oxide. If the level of ethoxylation is too low the surfactant may not be water soluble at temperatures less than 30°C, and if it is too high no cloud point may exist.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 30-Sep-2009
• ICS: 71.100.40 - Surface active agents
• Technical Committee: D12 - Soaps and Other Detergents
• Drafting Committee: D12.15 - Physical Testing

Relations

• Replaces: ASTM D2024-65(2003) - Standard Test Method for Cloud Point of Nonionic Surfactants
• Effective Date: 01-Oct-2009
• Referred By: ASTM D8179-18 - Standard Guide for Characterizing Detergents for the Cleaning of Clinically-used Medical Devices
• Effective Date: 01-Oct-2009
• Referred By: ASTM D4252-89(2017) - Standard Test Methods for Chemical Analysis of Alcohol Ethoxylates and Alkylphenol Ethoxylates
• Effective Date: 01-Oct-2009

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D2024 − 09
Standard Test Method for
1
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 (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
not sharp, that is, if it does not take place within a range of 1°C, this test
1. Scope
method is not appropriate.
1.1 This test method covers a procedure to determine the
“cloud point” of nonionic surfactants or detergent systems.
4. Interferences
Cloud Point is the temperature at which dissolved components
4.1 Ionicsurfactantsordetergentsinconcentrationsdownto
(solidsorliquids)arenolongercompletelysoluble,precipating
1 % or less of the nonionic surfactant drastically raise the
as a second phase giving the fluid a cloudy appearance. It is
characteristiccloudpointofthelatter.Thepresenceofsaltsand
limitedtothosesurfactantsanddetergentsystemsforwhichthe
bases (that is, non-surface active materials) will lower the
visible solubility change occurs over a range of 1°C or less at
characteristic cloud point, while acids tend to raise the cloud
concentrations of 0.5 to 1.0 % in DI water between 30 and
point.
95°C.
1.2 ChemicalLimitations—Nonionicsurfactantsthatexhibit
5. Apparatus
a characteristic cloud point in general terms consist of a
5.1 Thermometer—AnASTM Partial ImmersionThermom-
water-in-soluble moiety condensed with 50 to 75 % by weight
eter having a range from−20 to+150°C or 0 to 302°F and
of ethylene oxide. If the level of ethoxylation is too low the
conforming to the requirements for Thermometer 1C or 1F in
surfactant may not be water soluble at temperatures less than
accordance with Specification E1.
30°C, and if it is too high no cloud point may exist.
1.3 This standard does not purport to address all of the
6. Procedure
safety concerns, if any, associated with its use. It is the
6.1 Prepare a 1.0 % test solution by weighing a 1 6 0.1-g
responsibility of the user of this standard to establish appro-
sample into a 150-mL beaker and add 99 g of distilled or
priate safety and health practices and determine the applica-
de-mineralized water which is at a temperature of less than
bility of regulatory limitations prior to use.
30°C,i.e.roomtemperature.Mixuntilthesampleisdissolved;
2. Referenced Documents initial sample should be clear and homogeneous. Pour 50 6 2
2
mLof test solution into a 25 by 200-mm borosilicate glass test
2.1 ASTM Standards:
tube.Placethefilledtesttubeintoa1000mLbeakerwaterbath
E1Specification for ASTM Liquid-in-Glass Thermometers
containing900mLofwaterandamagneticstirrer.Positionthe
tube on an angle so it rests in the pour point of the beaker.
3. Significance and Use
Insert a thermometer into the test tube and in the water bath to
3.1 The cloud point temperature is a reproducible charac-
monitor temperatures. Slowly heat water bath and sample at a
teristic of certain pure nonionic surfactants. It is also charac-
rate of
...

This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation:D2024–65 (Reapproved 2003) Designation: D2024 – 09
Standard Test Method for
1
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 (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope
1.1This test method covers the determination of the solubility inversion temperature or “cloud point” of nonionic surfactants or
detergent systems which are characteristically less soluble in water at higher temperatures than at lower temperatures. It is limited
to those surfactants and detergent systems for which the visible solubility change occurs over a range of 1°C or less at
concentrations of 0.5 to 1.0 % in water between 30 and 95°C.
1.1 This test method covers a procedure to determine the “cloud point” of nonionic surfactants or detergent systems. Cloud
Pointisthetemperatureatwhichdissolvedcomponents(solidsorliquids)arenolongercompletelysoluble,precipatingasasecond
phase giving the fluid a cloudy appearance. It is limited to those surfactants and detergent systems for which the visible solubility
change occurs over a range of 1°C or less at concentrations of 0.5 to 1.0 % in DI water between 30 and 95°C.
1.2 Chemical Limitations—Nonionic surfactants that exhibit a characteristic cloud point in general terms consist of a
water-in-soluble moiety condensed with 50 to 75 % by weight of ethylene oxide. —Nonionic surfactants that exhibit a
characteristic cloud point in general terms consist of a water-in-soluble moiety condensed with 50 to 75 % by weight of ethylene
oxide. If the level of ethoxylation is too low the surfactant may not be water soluble at temperatures less than 30°C, and if it is
too high no cloud point may exist.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
E1 Specification for ASTM Liquid-in-Glass Thermometers
3. Significance and Use
3.1 The cloud point temperature is a reproducible characteristic of certain pure nonionic surfactants. It is also characteristic of
certain nonionic surfactant formulated systems. This test method is appropriate for both systems.
NOTE 1—Ifthetransitionfromadistinctlycloudytoaclearsolutionisnotsharp,thatis,ifitdoesnottakeplacewithinarangeof1°C,thistestmethod
is not appropriate.
4. Interferences
4.1 Ionic surfactants or detergents in concentrations down to1%or less of the nonionic surfactant drastically raise the
characteristic cloud point of the latter. The presence of salts and bases (that is, non-surface active materials) will lower the
characteristic cloud point. Acidspoint, while acids tend to raise the cloud point.
5. Apparatus
5.1 Thermometer—An ASTM Partial Immersion Thermometer having a range from−20 to+150°C or 0 to 302°F and
conforming to the requirements for Thermometer 1C or 1F in accordance with Specification E1.
1
This test method is under the jurisdiction ofASTM Committee D12 on Soaps and Other Detergents and is the direct responsibility of Subcommittee D12.15 on Physical
Testing.
Current edition approved Aug. 31, 1965. Published October 1965. Originally published as D2024–62T. Last previous edition D2024–62T. DOI: 10.1520/D2024-65R03.
Current edition approved Oct. 1, 2009. Published November 2009. Originally approved in 1962 as D2024–62T. Last previous edition approved in 2003 as
D2024–65(2003). DOI: 10.1520/D2024-09.
2
ForreferencedASTMstandards,visittheASTMwebsite,www.astm.org,[e-mail]ards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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D2024 – 09
6. Procedure
6.1Prepare a 1.0 % test solution by weighing a 1 6 0.1-g sample into a 150-mL beaker and add 100 mL of distilled or
demineralized water which is at a temperature of less than 30°C. Agitate until the sample is dissolved. Pour 50 6 5 mL of te
...