- ▸ Corrosion inhibitor: Inhibits corrosion of metal in water-contact systems.
- ▸ Cooling water treatment: Corrosion control in recirculating/cooling water.
- ▸ Water-treatment formulations: Phosphonate additive in industrial water programs.
A grade-specific Safety Data Sheet (SDS) — with the complete hazard classification, handling precautions, and transport information — is supplied with every shipment and available on request. Confirm all safety and regulatory details against the SDS for your specific grade.
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Transport classification per the UN Model Regulations / 49 CFR 172.101 Hazardous Materials Table. Confirm against the grade-specific SDS (Section 14) before shipping.
2-Hydroxyphosphonocarboxylic Acid (CAS 23783-26-8), known as HPAA, is an organophosphonic acid used as a corrosion inhibitor. It is applied in industrial water-treatment programs, where phosphonates of this type protect metal surfaces in recirculating and cooling-water systems.
Frequently Asked Questions
What is 2-hydroxyphosphonocarboxylic acid (HPAA)?
HPAA (CAS 23783-26-8, C2H5O6P) is an organophosphonic acid used as a corrosion inhibitor in industrial water treatment. Phosphonates of this type help protect metal surfaces in recirculating and cooling-water systems. RawSource supplies it in bulk to water-treatment formulators.
What is HPAA used for?
HPAA is used as a corrosion inhibitor in industrial water-treatment programs, particularly for corrosion control of metal in recirculating and cooling-water systems. It is incorporated as a phosphonate additive in cooling-water and process-water formulations.
Is HPAA the same as phosphonic acid or phosphoric acid?
No. HPAA is a specific hydroxyphosphonocarboxylic acid (CAS 23783-26-8) containing both a phosphonate (C-P) group and a carboxylic acid group. It is distinct from inorganic phosphoric acid and from simple phosphonic acid. Identity should be confirmed by CAS number on the CoA.
What CAS number and HS code apply to HPAA?
The CAS number is 23783-26-8. It classifies under HS 2931.49 (non-halogenated organo-phosphorus derivatives, other). Confirm the destination tariff line with your customs broker.
How is bulk HPAA supplied and quoted?
RawSource supplies HPAA in bulk for water-treatment blending, typically as an aqueous solution in drums, totes, and IBCs. Pricing is volume-dependent; request a bulk quote with your target quantity and active-content requirement. CoA and SDS are provided with each shipment.