Aluminum corrosion hazards?

[er9]

I'm trying to figure out what the aluminum on my boat is corroding into and what hazards they pose.

Still researching but havn't come across anything specific to my problems and questions.

I have two issues that i'm sure that almost all of us have on older boats and i just want to clarify. First is...at the base of the mast, the aluminum has corroded. When i bought the boat the bilge had water leaking from the two fresh water tanks. the water level was covering the bottom three to four inches of the mast for quite some time. There was a thick layer of dissolved aluminum sludge at the base of the mast. ive solved the leak problem, the bilge has been dry for months and this sludge has dried to a powder.

I'm under the impression this sludge was aluminum chloride. after a quick search of aluminum chloride (really nasty stuff) im a bit concerned as it can cause blindness. got me wondering first am i correct? is this aluminum chloride and if so would stirring up this dust trying to clean up the mast base be a serious hazard?

my second question is related. the same sludge resides heavily in my old water tanks. are these tanks safe to use for showering and washing? i'm not drinking from them but am concerned.

iv'e never heard of or read of any issues yet but am still researching. Unfortunately new tanks are a few months away but will be living aboard full time in a couple of weeks.

[thinwater]

Originally Posted by er9

I'm trying to figure out what the aluminum on my boat is corroding into and what hazards they pose.

Still researching but havn't come across anything specific to my problems and questions.

I have two issues that i'm sure that almost all of us have on older boats and i just want to clarify. First is...at the base of the mast, the aluminum has corroded. When i bought the boat the bilge had water leaking from the two fresh water tanks. the water level was covering the bottom three to four inches of the mast for quite some time. There was a thick layer of dissolved aluminum sludge at the base of the mast. ive solved the leak problem, the bilge has been dry for months and this sludge has dried to a powder.

I'm under the impression this sludge was aluminum chloride. after a quick search of aluminum chloride (really nasty stuff) im a bit concerned as it can cause blindness. got me wondering first am i correct? is this aluminum chloride and if so would stirring up this dust trying to clean up the mast base be a serious hazard?

my second question is related. the same sludge resides heavily in my old water tanks. are these tanks safe to use for showering and washing? i'm not drinking from them but am concerned.

Iv'e never heard of or read of any issues yet but am still researching. Unfortunately new tanks are a few months away but will be living aboard full time in a couple of weeks.

Aluminum hydroxide. Not to worry. AlCl3 is unstable and basically does not exist outside of a lab.

[SealyTechSrvcs]

You should be OK for cleaning - always use proper PPE for handling chemicals (lab goggles, gloves, and at least a paper mask). As far as using the tank, I specify a rhino-lining like coating for all tanks (fuel and potable water) in the custom boats that we design. This prevents corrosion in the tanks and makes them easier to clean. We also use is sometimes in lockers on steel vessels.

[Stumble]

What caused the damage was likely the chloride, but it is so reactive it quickly breaks down and leaves you with aluminium oxides. I wouldn't eat it, but it won't cause any real issues. I do suggest wearing a dust mask when cleaning any powder like substance, that stuff can cause lung irritation even if it is chemically benign.