Sodium Hexafluorosilicate Storage — Na2SiF6 Drinking-Water Fluoridation Tank

Storing Sodium Hexafluorosilicate? Start Here

Sodium hexafluorosilicate is a key player in water fluoridation, especially for smaller water systems where handling dry materials is more practical than dealing with liquid chemicals. This white-to-off-white powder is not just for water treatment; it's also used in glass and ceramic production, and even as a mothproofing agent. If you're considering using it, understanding the right storage solutions is crucial to ensure safety and efficiency.

Can you store it in a poly tank?

Yes, sodium hexafluorosilicate can be stored in high-density polyethylene (HDPE) or cross-linked polyethylene (XLPE) tanks. These materials are ideal for handling the mildly acidic nature of its saturated solution. Avoid using glass, silica, or concrete without protective coatings, as the chemical can cause etching and degradation.

Watch Out for Fluoride Attack

When storing sodium hexafluorosilicate, be aware of its potential to attack glass, silica, and concrete. This is the same chemistry that makes it useful for etching glass. Ensure all storage and handling equipment is appropriately lined or made from compatible materials like HDPE or PVC to prevent damage.

The safety that actually matters

• Always use proper personal protective equipment (PPE) to avoid skin and inhalation exposure.
• Ensure good ventilation in storage and handling areas to minimize inhalation risks.
• Store in a cool, dry place to maintain chemical stability and prevent accidental exposure.

Common questions

Is sodium hexafluorosilicate safe for drinking water?

Yes, it's EPA-approved for water fluoridation when used correctly, adhering to safety guidelines.

What gaskets should I use?

EPDM gaskets are standard for this application, but always match gaskets to the manufacturer's compatibility chart.

Can I use stainless steel tanks?

316L stainless steel is acceptable for neutral pH solutions, but not ideal for prolonged contact with fluoride-rich solutions.