Epichlorohydrin Storage & Tank Compatibility

Storing Epichlorohydrin? Start Here

Epichlorohydrin (_C3H5ClO, CAS 106-89-8) is a clear, colorless, mobile liquid with a sharp, chloroform-like odor and a structure that combines a reactive three-membered epoxide ring with a chloromethyl group. That dual reactivity makes it one of the most important building blocks in industrial chemistry: it is the principal precursor to bisphenol-A and bisphenol-F epoxy resins, to synthetic glycerin, to wet-strength paper resins, to ion-exchange media, and to a range of specialty elastomers and surfactants. The same reactivity that makes it valuable also makes it dangerous. Epichlorohydrin is flammable, acutely toxic by every route of exposure, corrosive to skin and eyes, a confirmed sensitizer, and classified as a probable human carcinogen and mutagen. It hydrolyzes slowly in water to acidic products, so storage systems must keep the product dry, cool, inhibited, and sealed against air and moisture.

Is Epichlorohydrin Compatible With Polyethylene (HDPE / XLPE) Tanks?

The honest answer is: conditionally, and only within tight limits. Mainstream polyethylene chemical-resistance charts, including the Braskem polyethylene resistance bulletin and common HDPE pipe and tank resistance guides, list epichlorohydrin as resistant (marked plus or R) to MDPE and HDPE at ambient temperature, roughly 20 to 23 C. Polyethylene bottles and HDPE containers are in fact used to package laboratory and small-volume quantities. That places epichlorohydrin in a different class from aromatic, chlorinated, and ketone bulk solvents that swell and stress-crack polyethylene outright.

That said, epichlorohydrin is a reactive chlorinated epoxide, not an inert salt solution, so we rate HDPE and XLPE as Conditional rather than fully recommended. Resistance is documented at ambient; published data does not support warm or hot immersion, and prolonged contact at elevated temperature can lead to absorption, softening, and loss of mechanical strength. For any bulk or long-duration storage we steer customers to 316 stainless steel or fluoropolymer-lined vessels. If polyethylene is used for secondary containment or short-term ambient duty, confirm the specific resin grade, wall thickness, and service temperature with the tank manufacturer before committing the vessel, and keep the product dry to avoid acidic hydrolysis byproducts.

Material compatibility at a glance

Epichlorohydrin is best stored in dry, inhibited form in 316 stainless steel or fluoropolymer-lined vessels with PTFE or fluoroelastomer seals. Published polyethylene resistance charts rate HDPE as resistant at ambient temperature, so HDPE or XLPE may serve secondary containment or short-term ambient duty, but as a reactive chlorinated epoxide it warrants a conditional rating: ambient only, no elevated-heat immersion, and manufacturer sign-off on resin and wall section. Avoid PVC, CPVC, polypropylene, and common rubber seals. Keep the product dry, because contact with water hydrolyzes it to acidic byproducts that drive corrosion.

Ratings: S suitable · C conditional / limited · U unsuitable. Verify against the cited resistance charts and your concentration/temperature before specifying.

The safety that actually matters

• Treat as a CMR substance: epichlorohydrin may cause cancer (H350), may cause genetic defects (H340), and may damage fertility or the unborn child (H360). Follow your engineering controls and exposure-limit program rigorously.
• It is fatal if inhaled (H330) and toxic by skin contact and ingestion. Use closed transfer, local exhaust ventilation, and supplied-air respiratory protection where vapor exposure is possible.
• It causes severe skin burns and serious eye damage (H314, H318) and is a respiratory and skin sensitizer (H317, H334). Wear chemical-resistant gloves, full face and eye protection, and impervious clothing; provide emergency eyewash and shower.
• It is a flammable liquid (H226), flash point about 34 C; keep away from heat, sparks, and open flame, bond and ground during transfer, and use explosion-rated equipment.
• Keep the product dry and cool; contact with water drives slow hydrolysis to acidic, corrosive byproducts. Avoid contact with strong oxidizers, strong acids and caustics, and with zinc, aluminum, and iron and aluminum chlorides, which can trigger violent reaction.
• Provide secondary containment sized to the largest vessel and protect waterways; the material is harmful to aquatic life (H402, H412).

Common questions

Can I store epichlorohydrin in an HDPE or XLPE tank?

Conditionally and only at ambient temperature. Polyethylene resistance charts rate HDPE as resistant to epichlorohydrin near 20 to 23 C, and HDPE is used for small containers, but because it is a reactive chlorinated epoxide we rate it Conditional. For bulk or long-term storage choose 316 stainless steel or a fluoropolymer-lined vessel, and confirm resin grade and service temperature with the tank manufacturer.

What is the NFPA 704 rating for epichlorohydrin?

Health 4, Flammability 3, Instability 2, with the special W notation meaning it reacts with water. The Health 4 reflects that it can be lethal under emergency conditions, and the W warns that contact with water yields acidic hydrolysis products.

Why does epichlorohydrin need to be kept dry?

Epichlorohydrin hydrolyzes slowly in the presence of water and moisture to form acidic byproducts. Those acids promote corrosion of metal systems and degrade product quality, so storage should be sealed, inhibited, and protected from humidity, water ingress, and air.

What gaskets and seals work with epichlorohydrin?

Fluoropolymers such as PTFE and PVDF, and fluoroelastomer seals, give the best service. Common elastomers like Buna-N, EPDM, and natural rubber are attacked or swell and should be avoided. Always confirm seal material against the supplier safety data sheet for your specific conditions.