Separate aluminium from brass threaded bushing without affecting the brass

I wanted to separate aluminium from brass threaded bushing without affecting the brass.


I also suppose that brass isn't the brass but it's a phosphor bronze.


Does brass and phosphor bronze amalgamate with mercury without scratching?


Is it possible to dissolve aluminium without affecting the brass?


I've also read that aluminium can corrode in the presence of brass, but I suppose brass is isolated from bushing or pressed really tight to prevent corrosion.


