The inner bottle of a standard IBC tank is made from High-Density Polyethylene (HDPE), one of the most chemically resistant plastics available. However, HDPE is not universally compatible with all chemicals. Storing an incompatible substance can cause the bottle to swell, crack, soften, or fail catastrophically -- resulting in hazardous spills, product loss, and potential injury. This guide provides a comprehensive compatibility reference for the most commonly stored chemicals in IBC tanks.
Important Disclaimer
This guide is provided for general reference only. Chemical compatibility is affected by concentration, temperature, exposure duration, and the presence of other chemicals. Always consult the chemical manufacturer’s Safety Data Sheet (SDS) and the IBC manufacturer’s recommendations before storing any chemical. When in doubt, request a compatibility test coupon or contact our team at Omaha IBC Tanks for guidance.
Understanding Compatibility Ratings
Chemical compatibility is typically rated on a scale that considers the effect of the chemical on the container material over time. Here is the rating system used in this guide:
Excellent
No effect. Safe for long-term storage.
Good
Minor effect. Suitable for limited exposure.
Fair
Moderate effect. Short-term only. Test first.
Not Recommended
Severe attack. Do not store in HDPE.
HDPE Compatibility Chart: Common Chemicals
Acids
| Chemical | Concentration | 68°F / 20°C | 140°F / 60°C |
|---|---|---|---|
| Acetic Acid | Up to 50% | A | B |
| Acetic Acid | Glacial (100%) | B | C |
| Citric Acid | All concentrations | A | A |
| Hydrochloric Acid | Up to 37% | A | B |
| Nitric Acid | Up to 50% | B | C |
| Nitric Acid | 70% (concentrated) | D | D |
| Phosphoric Acid | Up to 85% | A | B |
| Sulfuric Acid | Up to 70% | A | B |
| Sulfuric Acid | 90-98% | D | D |
| Chromic Acid | Up to 50% | C | D |
Bases & Alkalis
| Chemical | Concentration | 68°F / 20°C | 140°F / 60°C |
|---|---|---|---|
| Ammonium Hydroxide | All concentrations | A | A |
| Calcium Hydroxide | Saturated | A | A |
| Sodium Hydroxide (Lye) | Up to 50% | A | B |
| Potassium Hydroxide | Up to 50% | A | B |
| Sodium Hypochlorite (Bleach) | Up to 12.5% | A | B |
Solvents
| Chemical | 68°F / 20°C | 140°F / 60°C | Notes |
|---|---|---|---|
| Acetone | B | D | Short-term only at room temp |
| Benzene | D | D | Causes severe swelling |
| Methylene Chloride | D | D | Dissolves HDPE rapidly |
| Toluene | D | D | Causes rapid swelling and softening |
| Xylene | D | D | Incompatible with HDPE at any temp |
| Mineral Spirits | C | D | Slight swelling at room temp |
| Turpentine | C | D | Short-term only |
Oils & Fuels
| Chemical | 68°F / 20°C | 140°F / 60°C | Notes |
|---|---|---|---|
| Vegetable Oil | A | A | Excellent compatibility |
| Motor Oil | B | C | Slight absorption over time |
| Diesel Fuel | B | C | Some swelling with extended contact |
| Gasoline | D | D | Aromatic components attack HDPE |
| Hydraulic Fluid | B | C | Depends on specific fluid type |
Alcohols & Common Solutions
| Chemical | Concentration | 68°F / 20°C | 140°F / 60°C |
|---|---|---|---|
| Ethanol (Ethyl Alcohol) | Up to 95% | A | B |
| Isopropyl Alcohol (IPA) | Up to 100% | A | B |
| Methanol | 100% | A | B |
| Ethylene Glycol | All concentrations | A | A |
| Propylene Glycol | All concentrations | A | A |
| Hydrogen Peroxide | Up to 30% | A | B |
| Formaldehyde | Up to 40% | A | B |
Temperature Effects on Compatibility
Temperature is a critical variable in chemical compatibility. As a general rule, every 18°F (10°C) increase in temperature roughly doubles the rate of chemical attack on HDPE. A chemical rated “A” at room temperature may degrade to “B” or “C” at elevated temperatures. This is why the charts above include ratings at both 68°F and 140°F.
For heated IBC applications, such as storing viscous products that need to be kept warm for dispensing, it is critical to verify compatibility at the actual storage temperature, not just room temperature. See our IBC heating solutions guide for safe heating methods that maintain even temperature distribution and avoid hot spots.
Concentration Limits
Many chemicals are compatible with HDPE at dilute concentrations but become aggressive at higher concentrations. Key examples:
- Nitric acid is acceptable up to about 50% concentration at room temperature, but concentrated nitric acid (70%+) is a powerful oxidizer that attacks HDPE aggressively.
- Sulfuric acid is compatible up to about 70% concentration. Above 90%, it becomes a dehydrating agent that damages polyethylene.
- Acetic acid is excellent up to 50% but glacial (100%) acetic acid can cause environmental stress cracking over time, especially at elevated temperatures.
- Hydrogen peroxide is compatible up to 30%, but higher concentrations are strong oxidizers that degrade HDPE and may create pressure buildup from oxygen gas evolution.
Chemicals That Should Never Be Stored in HDPE IBCs
The following substances are categorically incompatible with HDPE and must never be stored in standard IBC tanks:
- ⚠Aromatic hydrocarbons: Benzene, toluene, xylene, and their derivatives cause severe swelling and softening of HDPE within hours.
- ⚠Chlorinated solvents: Methylene chloride, chloroform, carbon tetrachloride, and trichloroethylene dissolve HDPE rapidly.
- ⚠Strong oxidizers (concentrated): Concentrated nitric acid (70%+), concentrated sulfuric acid (90%+), oleum, and chromic acid at high concentrations.
- ⚠Bromine and fluorine: Elemental halogens (except chlorine in dilute aqueous solution) attack HDPE directly.
- ⚠Gasoline and jet fuel: The aromatic fraction (especially in premium gasoline) causes swelling and permeation through HDPE walls.
Environmental Stress Cracking (ESC)
Even chemicals rated “A” for HDPE resistance can cause a phenomenon called environmental stress cracking (ESC) under the right conditions. ESC occurs when a chemical that does not dissolve or swell the plastic instead accelerates crack growth at points of residual stress -- such as near molded corners, valve fittings, or areas that have been scratched or dented. Common ESC agents include surfactants (detergents, wetting agents), silicone oils, and even some food-grade oils at elevated temperatures.
To minimize ESC risk: keep IBCs away from excessive heat, avoid over-tightening fittings, handle the bottle gently during maintenance, and replace bottles that show any signs of surface cracking. For more on extending your IBC’s useful life, see our IBC tank lifespan guide.
Special Considerations for UN-Rated IBCs
If you are transporting hazardous materials, the IBC must carry a current UN rating for the specific hazard class and packing group of the chemical being shipped. Chemical compatibility of the HDPE is a necessary but not sufficient condition -- the IBC must also be tested and certified for the specific type of dangerous goods. Consult our IBC regulations guide for details on DOT and UN compliance requirements.
Get Expert Guidance
If you are unsure whether a particular chemical is safe to store in an HDPE IBC tank, do not guess. Contact our team at Omaha IBC Tanks with the chemical name, concentration, and storage temperature, and we will help you determine the right container solution. We stock new and reconditioned IBC tanks suitable for a wide range of chemical applications, and we can source specialty containers for aggressive chemicals that require cross-linked polyethylene or fluorinated HDPE bottles.