Citric Acid (C6H8O7, CAS 77-92-9) is a white crystalline organic acid made by fermentation. It is very soluble in water and often supplied as a 50% solution with a specific gravity of about 1.24. It is used as a food and beverage acidulant, a chelating agent in cleaners and detergents, for descaling and metal passivation, and in pharmaceuticals and cosmetics. Food-grade citric acid storage requires food-contact tank materials. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.
HDPE is the most economical tank material for Citric Acid, rated Excellent. Polypropylene, nylon and PVDF (Kynar®) are also rated Good or better. Rated Fair (contact us before use): aluminum hardware.
How Citric Acid works with the plastics used to make our storage tanks.
| Material | Relative cost | Rating |
|---|---|---|
| HDPE $ | $$$$ | A Excellent |
| Polypropylene $$ | $$$$ | A Excellent |
| Nylon $$$ | $$$$ | A Excellent |
| PVDF (Kynar®) $$$$ | $$$$ | A Excellent |
How Citric Acid works with the plastics used for tank fittings.
| Material | Rating |
|---|---|
| HDPE | A Excellent |
| PVC | B Good |
| CPVC | B Good |
| Polypropylene | A Excellent |
| PVDF | A Excellent |
How Citric Acid works with gasket and O-ring materials.
| Material | Rating |
|---|---|
| Buna-N | A Excellent |
| EPDM | A Excellent |
| Viton® | A Excellent |
How Citric Acid works with the metals used for fittings and bolts.
| Material | Rating |
|---|---|
| 316 Stainless Steel | A Excellent |
| Hastelloy | A Excellent |
| Titanium | — No Data |
| Aluminum | C Fair |
Storing this chemical in PVDF?
PVDF tanks from 25 to 5,000 gallons with fittings installed. Confirm concentration and temperature with us before you order.
Send the chemical, concentration, temperature and size. We’ll match the tank and fittings and send a quote.