[Jimbo80008]

This might be a strange question but imagine you have a beaker filled with small grains of Bismuth metal, carbon and aluminium oxide, what would be the best way to seperate the aluminium oxide out of the beaker without losing any of the bismuth or carbon? for clarity, I only need the aluminium oxide out of the beaker, the carbon and bismuth may remain mixed in the beaker.

[Borek]

Sounds quite homeworkish. What are your thoughts?

[Jimbo80008]

well you are not wrong. Its my first time posting on the forum so my excuse for misplacing the post. Its a problem i ran into while working on a school project.

[Aldebaran]

An interesting question which might provoke some creative discussion. I’m thinking vacuum distillation might have a role to play

[rjb]

In my opinion, you're looking for a reagent which will react with aluminium oxide to form a new (ideally water) soluble compound, but will leave the other components untouched. This would allow you to filter out of insoluble Carbon and Bismuth which could be returned to the beaker. The filtrate would contain your new aluminium compound which could (if you wanted) undergo further reaction to produce aluminium oxide, your original compound.

As a possible clue, you might like to think a little about the reactions of aluminium oxide and common bench acids remembering of course that you do have to consider the reactions of these with the Bismuth present also.

P.s. Where are you from? Just curious as I noticed that you spell Aluminium the correct way, so clearly not the US!

[Enthalpy]

Flotation might work, as the density differences seem usable.

Melting the bismuth away seems simple and would be a step to the solution. It won't be grains any more afterwards.