Acetone COA + batch traceability — what a verified plant must produce
How a verified plant ships acetone — what a per-batch CoA must contain, how the sealed retain sample programme works, and how to verify the CoA matches the lot you actually receive.
Why batch CoA matters
Bulk acetone is one of the cheapest reagents in chemistry, but off-spec acetone hides downstream costs that dwarf the unit price: a single 1 ppm aldehyde overshoot can ruin an entire pharmaceutical recrystallisation step. A verified plant treats the per-batch CoA as a binding quality document, not a marketing PDF.
What a credible CoA must include
- Batch number + production date — must round-trip to the drum / IBC label and the bill of lading.
- Assay (GC) ≥ 99.5% with the GC method reference (typically ASTM E681 or ISO 22995).
- Water content (Karl-Fischer) — for industrial grade ≤ 0.30%; tighter for reagent / pharma.
- Acidity, expressed as acetic acid — drift here means oxidation; freshness check.
- Permanganate time — reducing-substance proxy.
- Non-volatile residue — solids check.
- Signature + date of the QA manager (named, not stamped).
Sealed retain-sample programme
ChemExact-verified plants keep a 2 × 250 mL sealed retain sample of every production batch for 3 years in a temperature-controlled archive. If your incoming QC flags an anomaly, you can request the retain sample for re-test by an independent lab. This breaks the "the supplier swears it was in spec at dispatch" stalemate.
How to verify on receipt
- Compare batch number on the CoA to the drum head label and the commercial invoice.
- Pull a 100 mL sample under N2 from each drum (or from the tote / ISO tank dip-tube).
- Run a water KF and GC assay in your incoming QC.
- If results deviate > 0.5% from the CoA, freeze the lot and request the sealed retain.
Common failure modes
- Photocopied CoAs without signature — refuse.
- Batch number mismatch between CoA and drum label — refuse and quarantine.
- Outdated test methods (ASTM withdrawn 1990s spec) — ask for an upgraded retest.
Frequently asked
Does industrial-grade acetone need a CoA per batch?
Yes — even at industrial grade, a per-batch CoA is the standard. If a supplier offers "generic" CoA on letterhead, that's a dealbreaker for any audited downstream use.
Can I request a retain sample from a previous shipment?
Verified plants keep retains for 3 years. Email your supplier's QA team with the batch number and the request will normally be honoured within 5-10 working days.
What's the cheapest way to spot a falsified CoA?
Check the QA-manager signature is hand-signed (not stamped), and that the batch number on the CoA matches the drum-head label. > 80% of forged CoAs fail at least one of these two.