Activated Alumina Desiccant specifications
| Property | Unit | Ø1–2 mm | Ø2–3 mm | Ø3–5 mm | Ø4–6 mm | Test condition |
|---|---|---|---|---|---|---|
| Al₂O₃ content | % wt | ≥ 93 | ≥ 93 | ≥ 93 | ≥ 93 | — |
| Surface area | m²/g | ≥ 300 | ≥ 300 | ≥ 300 | ≥ 300 | BET |
| Pore volume | ml/g | ≥ 0.40 | ≥ 0.40 | ≥ 0.40 | ≥ 0.40 | — |
| Static water adsorption | % wt | ≥ 18 | ≥ 18 | ≥ 18 | ≥ 18 | RH 60%, 25 °C |
| Bulk density | g/ml | 0.68–0.75 | 0.68–0.75 | 0.68–0.75 | 0.68–0.75 | Tapped |
| Crush strength | N / ball | ≥ 40 | ≥ 80 | ≥ 130 | ≥ 150 | Avg. of 25 balls |
Where is Activated Alumina Desiccant used?
Activated alumina desiccant is used to dry compressed air, industrial gases and liquid hydrocarbons, and as a guard layer that protects molecular sieve from liquid water.
Air separation pre-purification
Bottom PPU layer that takes up bulk water.
Liquid drying
Dries LPG, solvents and transformer oil.
Activated Alumina Desiccant vs other adsorbents: which do you need?
Choose activated alumina for dew points down to about −40 °C and wet, acidic or liquid-laden feeds; use molecular sieve when you need −70 °C or lower.
| Desiccant | Typical dew point | Strength |
|---|---|---|
| Activated alumina (this product) | to about −40 °C | Tolerates liquid water, cheap to regenerate |
| 4A molecular sieve | to −70 °C and below | Deep drying, low outlet moisture |
| Silica gel | to about −40 °C | Can shatter in liquid water |
What is Activated Alumina Desiccant?
Activated alumina desiccant is a porous, high-surface-area form of aluminium oxide whose surface attracts and holds water molecules from gases and liquids.
Type
Activated aluminium oxide
Adsorbs
H₂O, acids, polar molecules
Form
Balls 1–2, 2–3, 3–5, 4–6 mm
How does Activated Alumina Desiccant work?
Water is adsorbed on the large internal surface of the alumina pores and released again when the bed is heated or purged with dry gas, so the same charge is used for years.
- Wet air or gas flows through the bed — usually from the bottom up.
- Water is adsorbed — outlet dew point falls to about −40 °C.
- Tower switches to regeneration — purge air or heat drives the water off.
When should you use Activated Alumina Desiccant?
Use activated alumina when you need reliable drying to around −40 °C, or a tough first layer that takes liquid water before a molecular sieve bed.
- Heatless or heated compressed-air dryers.
- Feeds that may carry liquid water or acid traces.
- Layered beds with 4A or 13X on top.
How do you regenerate Activated Alumina Desiccant?
Regenerate it with dry purge air in heatless dryers, or with hot air or gas at about 150–200 °C in heated dryers; it withstands thousands of cycles.
Heatless
15–20% dry purge air
Heated
150–200 °C
Service life
3–5 years
