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Phthalic Anhydride Storage Tank Selection

Storing Phthalic Anhydride? Start Here

Phthalic anhydride (PAN) is a versatile chemical used in making plasticizers, resins, and coatings. It comes as a solid or molten liquid, depending on your needs. When stored above 100°C, it can release fumes, so handling it with care is essential. If you're dealing with molten PAN, you'll need to keep it hot, between 140-160°C, to prevent it from solidifying.

Can you store it in a poly tank?

No, poly tanks are not suitable for storing molten phthalic anhydride. The high temperatures required for molten PAN exceed the limits of most plastics. Instead, use 316L stainless steel tanks, which can withstand the heat and prevent corrosion.

Watch out for fumes

When phthalic anhydride is heated, it can release fine particulate fumes. These fumes are the main exposure risk, so make sure your storage area is well-ventilated and that workers use appropriate respiratory protection.

The safety that actually matters

  • Ensure proper ventilation to manage fumes.
  • Use 316L stainless steel tanks for molten storage.
  • Equip workers with protective gear, especially respirators.

Common questions

Can I store solid phthalic anhydride in a poly tank?
Yes, but only in dry, indoor conditions at ambient temperatures.
What gasket material should I use?
Viton (FKM) is recommended for high-temperature applications with phthalic anhydride.
Why can't I use HDPE tanks?
HDPE tanks can't handle the high temperatures needed for molten phthalic anhydride.

Need a tank for this chemical?

Our team will confirm the right material and a freight quote to your ZIP. Call 866-418-1777 or browse the chemical compatibility database.

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Sources & References

All compatibility ratings, hazard classifications, and chemical identifiers on this page are sourced from authoritative third-party publications. Verify against the original references before final specification.

  1. PubChem Compound Database — entry for Phthalic Anhydride (CID 6811, CAS 85-44-9). pubchem.ncbi.nlm.nih.gov. National Library of Medicine / NCBI. Canonical chemical-identity reference.
  2. Snyder Industries Chemical Resistance Recommendations — system-of-construction guidance for polyethylene chemical-storage tanks at industrial ASTM 1.9 SG design rating. SNY-3041 Chemical Resistance Chart. Snyder Industries, current edition. Resin + fitting + gasket + bolt MOC matrix.
  3. Equistar Technical Tip — Chemical Resistance of Polyethylene — LDPE / MDPE / HDPE rating chart by concentration and temperature, distributed by Enduraplas. enduraplas.com (PDF). Equistar polyethylene resin chemical-resistance data, distributed via Enduraplas.
  4. NFPA 704: Standard System for the Identification of the Hazards of Materials for Emergency Response. nfpa.org. NFPA 704 'fire diamond' health/flammability/instability/special-hazard rating system (0–4 scale).
  5. UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS), current revision. unece.org/transport/ghs. GHS pictograms, signal words, and H-statement codes referenced in this guide.
  6. ASTM D1998 — Standard Specification for Polyethylene Upright Storage Tanks, current edition. astm.org. Cited as the design-specific-gravity standard (typically 1.9 SG) for industrial chemical-service polyethylene tanks.
  7. NIOSH Pocket Guide to Chemical Hazards — occupational exposure limits, PPE, and IDLH data for Phthalic Anhydride. cdc.gov/niosh/npg. CDC / NIOSH chemical-specific occupational-safety reference.

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