Aluminum Hydroxide
Aluminum Hydroxide (ATH, CAS 21645-51-2) with min. 64.5% Al2O3, supplied wholesale by Zyntex. Halogen-free, low-smoke flame retardant and filler for cables, rubber and plastics, and raw material for aluminum chemicals. CoA and SDS.
Description
Aluminum Hydroxide Product Overview
Aluminum hydroxide (Al(OH)3), also called alumina trihydrate (ATH), is a white, odorless powder that is insoluble in water but dissolves in strong acids and alkalis. It contains about 65% Al2O3 and about 35% chemically bound water.
When heated above about 200°C, aluminum hydroxide decomposes and releases its bound water. This reaction absorbs heat, cools the material, dilutes flammable gases and leaves a protective oxide layer, while producing very little smoke. That makes ATH the most widely used halogen-free flame retardant in cables, rubber, thermosets and plastics. It is often combined with Zinc borate or melamine-based additives such as Melamine cyanurate.
It is also used as a white filler in solid surfaces, paints and paper, and as the raw material for aluminum compounds such as Aluminum Sulfate, sodium aluminate and polyaluminum chloride used in water treatment.
Key Applications of Aluminum Hydroxide
Main application areas:
🔌 Cables and Wires
Halogen-free, low-smoke flame retardant in cable compounds.
🏭 Rubber and Plastics
Flame retardant filler in rubber, thermosets and thermoplastics.
🧱 Solid Surfaces
White filler in acrylic solid surfaces and engineered stone.
💧 Aluminum Chemicals
Raw material for aluminum sulfate, sodium aluminate and PAC.
Aluminum Hydroxide Technical Specifications
| Parameter | Standard Value |
|---|---|
| Product Name | Aluminum Hydroxide (ATH) |
| CAS Number | 21645-51-2 |
| EC Number | 244-492-7 |
| Molecular Formula / Weight | Al(OH)3 / 78.00 g/mol |
| Assay (Al2O3 Content) | Min 64.5% |
| Appearance | White amorphous or fine crystalline powder |
| Moisture (Surface) | Max 0.3% |
| Solubility | Insoluble in water and alcohol; soluble in strong acids and alkalis |
| Documents | CoA and SDS with every lot |
⚠️ Safety & Handling: Not classified as hazardous under GHS. Avoid inhaling fine dust and wear dust protection and eye protection when handling large quantities. Store in tightly closed bags in a dry place, away from strong acids and alkalis. Always consult the Safety Data Sheet (SDS) for full classification and handling instructions.
Frequently Asked Questions
How does aluminum hydroxide work as a flame retardant?
It decomposes above about 200°C, releasing water vapor. This absorbs heat, dilutes flammable gases and forms a protective oxide layer, with very low smoke generation.
Which particle sizes are available?
Several particle size grades can be offered, from fine grades for cables to coarser grades for fillers. Tell us your application when requesting a quote.
How can I get a price and documents?
Prices depend on quantity, packaging and destination. Contact us with your required volume to receive a quotation together with the CoA and SDS.
