How to Read Amine Class Results on a Fatty Amine COA
2026-11-10
How to Read Amine Class Results on a Fatty Amine COA
A batch of C12–14 alkyldimethylamine can meet the total amine value range while leaving another purchasing question unanswered: how much of the amine falls into the tertiary class? That is why a certificate of analysis may list total amine value, tertiary amine content, and primary plus secondary amines on separate lines. store.astm.org
What primary, secondary, and tertiary mean
These names count the organic groups attached to nitrogen. A primary amine has one, a secondary amine has two, and a tertiary amine has three. In C12–14 alkyldimethylamine, the three groups are one long alkyl chain and two methyl groups. amines (A00274)
Read each COA line against its own limit
| COA entry | What to check |
|---|---|
| Total amine value | The overall titratable amine response, commonly expressed in mg KOH/g. Compare it with the agreed range using the specified method. |
| Tertiary amine content | The reported amount of tertiary amine. Confirm how the percentage was calculated before comparing it with the minimum. |
| Primary and secondary amines | Whether the result covers both classes together or reports them separately. Apply the corresponding combined or individual limits. |
Total amine value sums the response from the amines measured by the method. Class-specific tests distinguish how that response is distributed. ASTM D2074 describes separate determinations for total, primary, secondary, and tertiary amine values in fatty amines. store.astm.org
Compare offers before approving a trial batch
Suppose a surfactant manufacturer is qualifying a second source for its oxidation line. One COA lists a total amine value and a combined primary-plus-secondary result. The other lists only a total amine value. If the plant’s specification includes a combined limit, ask the second supplier for that result and its test method before completing the comparison.
When sourcing C12–14 alkyldimethylamine as a tertiary amine intermediate, share your required tertiary amine minimum, primary and secondary amine limits, and reporting units with China Amines Co., Limited. Request the proposed grade specification and a representative COA for your review.
Technical references
- IUPAC Gold Book — Amines
- ASTM D2074 — Total, primary, secondary, and tertiary amine values of fatty amines
- ECHA — Amines, C12–14-alkyldimethyl