Standard Active Last Updated: Dec 27, 2016
ASTM D820-93(2016)

Standard Test Methods for Chemical Analysis of Soaps Containing Synthetic Detergents


These test methods detail the standard procedures for the chemical analysis of soaps containing synthetic detergents. The analytical procedures include the determination of the following chemical properties and substances: moisture and other matter volatile at a specified temperature; free alkali or free acid; anhydrous, salt-free soda soap; alcohol-soluble matter; matter insoluble in water; total alkalinity of matter insoluble in alcohol (alkaline salts); sodium silicate; phosphates; phosphates by colorimetric method using molybdenum blue); unsaponified and unsaponifiable matter; free fatty matter; chlorides in alcohol-soluble matter; rosin by McNicoll method; synthetic detergent by difference; and neutral inorganic salts.


1.1 These test methods cover procedures for the chemical analysis of soaps containing synthetic detergents.

1.2 The analytical procedures appear in the following order:





Moisture and Other Matter Volatile at 105°C (Oven Method)

5 and 6

Free Alkali or Free Acid

7 and 8

Anhydrous, Salt-Free, Soda Soap

9 – 12

Alcohol-Soluble Matter

13 and 14

Matter Insoluble in Water

15 and 15

Total Alkalinity of Matter Insoluble in Alcohol (Alkaline Salts)

16 and 17

Sodium Silicate

18 – 20


21 – 28

Phosphate (Colorimetric Method Using Molybdenum Blue)

29 – 34

Unsaponified and Unsaponifiable Matter

35 – 39

Free Fatty Matter


Chlorides in Alcohol-Soluble Matter

41 – 43

Rosin (McNicoll Method)

44 – 47

Synthetic Detergent (by Difference)


Neutral, Inorganic Salts


1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.4 This standard does not purport to address all of the safety problems, 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.

Contact Sales
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Book of Standards Volume: 15.04
Developed by Subcommittee: D12.12
Pages: 10
DOI: 10.1520/D0820-93R16
ICS Code: 71.100.40