Sodium Hydroxide (50%) (NaOH, CAS 1310-73-2) is a clear, highly corrosive alkaline solution with a specific gravity of about 1.53 that is made in the chlor-alkali process alongside chlorine. It is used in water and wastewater pH control, chemical manufacturing, pulp and paper, aluminum processing, food processing, soaps and cleaning chemicals. Because 50% NaOH starts to freeze near 54°F (12°C), outdoor sodium hydroxide tanks are often heat traced and insulated. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.
Safety data: Sodium Hydroxide Solution Safety Data Sheet (SDS) – Formosa Plastics USA
Polypropylene is the most economical tank material for Sodium Hydroxide (50%), rated Excellent. Nylon and HDPE are also rated Good or better. Avoid PVDF (Kynar®) tanks, PVDF fittings and Viton® gaskets. Rated Fair (contact us before use): Hastelloy hardware.
How Sodium Hydroxide (50%) works with the plastics used to make our storage tanks.
| Material | Rating |
|---|---|
| HDPE | |
| Polypropylene | |
| Nylon | |
| PVDF (Kynar®) |
How Sodium Hydroxide (50%) works with the plastics used for tank fittings.
| Material | Rating |
|---|---|
| HDPE | |
| PVC | |
| CPVC | |
| Polypropylene | |
| PVDF |
How Sodium Hydroxide (50%) works with gasket and O-ring materials.
| Material | Rating |
|---|---|
| Buna-N | |
| EPDM | |
| Viton® |
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