time necessary to dissolve e-scrap

[andu]

I have 8 liters of spent solution, but doesn't look this dark. I get a white salt when any drop dries up which I'd like to guess it's the aluminium chloride I still wanna filter the foils and do a fresh hcl time maybe rid of the grey particles. Picture with the plates is fresh, other two have few days.

 

[andu]

Alright I made a mess, poured two liters of acid, when i went back it had all evaporated and had the crystaline semi-transparent thing, so i poured some tap water, and now i have this sludge I should believe is aluminium oxide? Luckily most I dissolved is in different containers now and this was just latest attempt to finish dissolving this. Btw the other solution was amazingly thick.
image too big so had to upload here.

 

[andu]

Alright I made a mess, poured two liters of acid, when i went back it had all evaporated and had the crystaline semi-transparent thing, so i poured some tap water, and now i have this sludge I should believe is aluminium oxide? Luckily most I dissolved is in different containers now and this was just latest attempt to finish dissolving this. Btw the other solution was amazingly thick.
image too big so had to upload here.

any idea how i get rid of that? more acid doesn't seem to help.