[Ballistic]

How to safely clean Aluminium Powder container?

Hi guys, I have an empty HDPE bottle which used to contain fine Aluminium powder. Considering this substance cannot be made damp, how would you go about cleaning the bottle to use for something else?

I was thinking bottle brush, but then I'll be stuck with a powdery bottle brush?

cheers

B

[Borek]

Water with some detergent should do the trick IMHO.

You may try also some slightly alkaline solution.

[Stepan]

Aluminum powder is coated with wax. Detergent is better choice than the alkaline solution. The last one may give Hydrogen if reacts with Aluminum.

[Ballistic]

I don't believe this aluminium is coated with wax.

I am working on the assumption that the aluminium rapidly oxidises when damp and heats up rapidly igniting the released hydrogen.

[enahs]

The aluminum is already oxidized to aluminum oxide. No H was given off.

Just soap and water and scrubbing.
You could probably blow most of it out first with compressed air; but be very careful; inhaling the powder is very bad for your health, so wear PROPER equipment if you go this route.

[Arkcon]

I don't believe this aluminium is coated with wax.

I am working on the assumption that the aluminium rapidly oxidises when damp and heats up rapidly igniting the released hydrogen.

No.  Powdered aluminum doesn't react with water.  Magnesium metal, in bulk, reacts slowly with hot water, releasing hydrogen, so you may be confusing the two.

[Stepan]

I don't believe this aluminium is coated with wax.

I am working on the assumption that the aluminium rapidly oxidises when damp and heats up rapidly igniting the released hydrogen.

Powdered aluminum spiked with stearates, polystyrene or similar materials during production. They serve as passivators to prevent dust detonation and Al self ignition. This is why Aluminum Powder is hydrophobic.   

[Stepan]

I don't believe this aluminium is coated with wax.

I am working on the assumption that the aluminium rapidly oxidises when damp and heats up rapidly igniting the released hydrogen.

No.  Powdered aluminum doesn't react with water.  Magnesium metal, in bulk, reacts slowly with hot water, releasing hydrogen, so you may be confusing the two.

Aluminum would react with water if it wouldn't be passivated. Al does react with water in anaerobic conditions or in presence of acid, base, or elemental mercury, which prevent formation of the protective alumina layer. 

[Borek]

Aluminum would react with water if it wouldn't be passivated. Al does react with water in anaerobic conditions

That's not the situation we are talking about, we are talking about small amount of dust staining walls of a container open to the atmosphere (air & humidity). Don't make things more complicated than they are.

[408]

I am working on the assumption that the aluminium rapidly oxidises when damp and heats up rapidly igniting the released hydrogen.

Not going to happen.  I have wet powdered aluminum many times.  Soap, water, scrub.  done.  Or dilute NaOH or dilute HCl solution

[Stepan]

That's not the situation we are talking about, we are talking about small amount of dust staining walls of a container open to the atmosphere (air & humidity). Don't make things more complicated than they are.

Sorry, I overlooked that we are talking a small scale. As an industrial chemist I was thinking more like 5m3 container and 1000 kg of powder.