Confirming EDTA free acid and sodium salt identities with three documents

Trial design and interpretation

Compare chemical name, CAS number and salt form on the quotation, SDS and label. Record free-acid assay and water-insoluble fraction separately. Ask for clarification if a supplier uses the solubility of a salt to describe the free acid.

Recording Free acid content

Free acid content (Mass fraction): ENVO published industrial grade ≥99.0%. Test the acid form and request separate water and metal impurity results. Loss on drying (Mass fraction): ENVO published free acid ≤0.2%. Check the method specified for the commercial acid form.

How can an order for EDTA avoid inadvertently specifying a neutralised salt?

Check the full substance name, CAS number and current SDS, then compare solubility in the intended solvent and the system pH. Industrial chelation: For the free acid, record dissolution conditions and endpoint pH. Compare complexation of the target ion.

What to record

• Quoted product name
• CAS number on label
• Chemical form
• Dissolution under specified conditions

Technical references

• ENVO public product information · Verify against the ordered grade and lot ↗

Products and processes