ASTM D4711-89(2003)

Standard Test Method for Sulfonic and Sulfuric Acids in Alkylbenzene Sulfonic Acids

SIGNIFICANCE AND USE
Alkylbenzene sulfonic acids are important intermediates in the synthetic detergent industry and are defined under “alkyl benzene sulfonate” in Terminology D 459. This test method is suitable for the rapid monitoring of the sulfonic and sulfuric acid levels, both of which have a vital bearing on final product performance and appearance.
SCOPE
1.1 This test method is applicable to the determination of sulfonic and sulfuric acids in branched and linear alkylbenzene sulfonic acids used as intermediates in synthetic detergents.
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 the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Material Safety Data Sheets are available for reagents and materials. Review them for hazards prior to usage.

General Information

• Status: Historical
• Publication Date: 25-May-1989
• ICS: 71.080.40 - Organic acids
• Technical Committee: D12 - Soaps and Other Detergents
• Drafting Committee: D12.12 - Analysis and Specifications of Soaps, Synthetics, Detergents and their Components

Relations

• Replaces: ASTM D4711-89(1995)e1 - Standard Test Method for Sulfonic and Sulfuric Acids in Alkylbenzene Sulfonic Acids
• Effective Date: 26-May-1989
• Replaced By: ASTM D4711-89(2009) - Standard Test Method for Sulfonic and Sulfuric Acids in Alkylbenzene Sulfonic Acids
• 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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D4711–89(Reapproved2003)
Standard Test Method for
Sulfonic and Sulfuric Acids in Alkylbenzene Sulfonic Acids
This standard is issued under the fixed designation D4711; 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
1.1 This test method is applicable to the determination of
sulfonic and sulfuric acids in branched and linear alkylbenzene
sulfonic acids used as intermediates in synthetic detergents.
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 the user of this standard to establish appro-
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use. Material Safety
Data Sheets are available for reagents and materials. Review
them for hazards prior to usage.
2. Referenced Documents
2.1 ASTM Standards:
D459 Terminology Relating to Soaps and Other Detergents
E180 Practice for Determining the Precision of ASTM
Methods for Analysis and Testing of Industrial and Spe-
cialty Chemicals
3. Summary of Test Method
3.1 A methanolic solution of the sample is titrated with
cyclohexylamine in methanol to yield a potentiometric curve.
(See Fig. 1.)The first inflection represents the neutralization of
strong acids, such as sulfonics and alkylsulfurics, and the first
hydrogen of sulfuric acid. The second inflection represents the
neutralization of the second hydrogen of sulfuric acid. The
amount of sulfonic acid is calculated based on the titrant
Solvent. Methanol A. Differentiating titration curve
volume of the first inflection minus that between the two
Titrant. 0.1 N Cyclohexylamine B. First derivative curve of the curve A
inflections. The amount of sulfuric acid meanwhile is calcu-
FIG. 1 Titration of a detergent intermediate containing alkyl
lated from the titrant volume between the two inflections,
sulfonic acid and sulfuric acids.
which is equivalent to the amount of base required for
neutralization of the bisulfate anion.
4. Significance and Use
4.1 Alkylbenzenesulfonicacidsareimportantintermediates
in the synthetic detergent industry and are defined under “alkyl
This test method is under the jurisdiction of ASTM Committee D12 on Soaps
and Other Detergents and is the direct responsibility of Subcommittee D12.12 on
benzene sulfonate” in Terminology D459. This test method is
Analysis of Soaps and Synthetic Detergents.
suitable for the rapid monitoring of the sulfonic and sulfuric
Current edition approved May 26, 1989. Published July 1989. Originally
acid levels, both of which have a vital bearing on final product
published as D4711-87. Last previous edition D4711-87.
performance and appearance.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
5. Interferences
the ASTM website.
3 5.1 Strong acids, like nitric and hydrochloric, interfere, as
Withdrawn. The last approved version of this historical standard is referenced
on www.astm.org. do weak acids, such as carboxylic acids. Small amounts of
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D4711–89 (2003)
water originally present in the sample do not interfere in the 9.2 Add a magnetic stirring bar, 100 mL of anhydrous
determination. However, if as much as 5 % of water is present methanol, and stir with a magnetic stirrer until dissolved.
in the total solution (solvent plus sample), the end point 9.3 Titrate potentiometrically on the automatic titrator using
becomes less sharp. the combination electrode until a curve yielding two breaks is
obtained. (See Fig. 1.)
6. Apparatus
9.4 Record the volume of titrant to the first break as V , and
that to the second break V .
6.1 Potentiometric Titrator, and combination calomel ref- 2
erence electrode.
10. Calculation
6.2 Buret Assembly, having a 20 mL buret.
10.1 Calculate the weight percent sulfuric acid (H SO ) and
2 4
6.3 Beaker, 180 mL tall form.
weight percent sulfonic acid (RSO H) as follows:
6.4 Volumetric Flask, Class A, 500 mL.
6.5 Magnetic Stirrer, and stirring bar. %H SO 5 ~V 2V !~N!~98.08!~100!/~W!~1000! (3)
2 4 2 1
7. Reagents and Materials
%RSO H 5 ~2V 2V !~N!~MW!~100!/~W!~1000! (4)
3 1 2
7.1 Methanol, anhydrous,
where:
7.2 Cyclohexylamine (0.10 N)—Dissolve 10 g of reagent
V,V = millilitres of titrant at the first and the second end
1 2
cyclohexylamine in 1000 mL of anhydrous methanol. Stan-
points respectively.
dardize against sulfamic acid as described in Section 8.
N = normality of titrant,
7.3 Sulfamic Acid, acidimetric standard.
W = sample weight, g, and
MW = average equivalent weight of sulfonic acid.
8. Standardization of 0.10N Cyclohexylamine
,
6 7
11. Precision and Bias
8.1 All standardizations should
...