Acid and GRP

[clyst]

HI all!

I'm in the sh one t again .I'v spilt battery acid, best part of a full battery, in the bilges of a Folk song . the bilges were dry when the spillage occured having just been cleaned prior to craning out. the acid has been sloshing about on the moorings for nearly 6 days. I'v cleaned the acid out (that was a job in it self!) and flushed with salt water.The bilges smell and feel OK but what about the long term effect? Is there anything else I should be doing? Will there be acid burning away in any grp scratches etc?

Any advice would be helpfull.

regards terry

 

[BrendanS]

I'm not an expert on this subject, but a quick fix based on simple chemistry would be to mix some baking soda into a bucket of water and slosh it round. If you see any fizzing, that is possibly the alkali neutralising the acid. Make sure it goes everywhere the acid could have reached. Give it half an hour then wash out again. A weak alkali like this won't do any harm, but will only be effective if the bulk of the acid is already cleaned out and rinsed as you've already done

If you've already *thoroughly* rinsed out, then I doubt there's anything much left of it to worry about

No idea what damage could have been caused while the acid was sitting there though.

 

[PaulAG]

Sorry to hear about this problem, but did you know that one of the fears of submariners in the days of diesel electric subs. was that of getting battery acid (sulphuric acid) mixed with seawater. Salt plus strong acid produces chlorine, a highly poisonous gas with very nasty effects on lungs. It was used for this purpose in WW1. Baking soda as suggested, would be a very good way of seeing if you have got all the acid washed out and neutralising any remaining.

PaulAG

 

[johmal]

Battery acid - as Sulphuric Acid goes is not that strong. The glass fibre won't react, and the resin should be reasonably inert as far as dilute sulphuric acid is concerned.

A good rinse, and baking powder as sujested would help.

I think you will be OK.

John M

 

[VicS]

Sulphuric acid is what is termed a strong acid, battery acid is roughly a 25%, by volume, solution in water.... fairly concentrated by most standards. With salt (sodium chloride) hydrgen chloride is formed not chlorine. This is a corrosive gas so is not very welcome but is not toxic like chlorine. An oxidising agent must be present to produce chlorine. Chlorine will, however, be produced if the acid in a battery becomes contaminated with salt.

The good news is that GRP is resistant to acid attack, at least to sulphuric acid (not so resistant to caustic alkali).

The best way of dealing with an acid spill of this nature is to flush away with copious quantities of water, as you have done, finally neutralising the last traces with a weak alkali such as sodium hydrogen carbonate (baking powder or bicabonate of soda) or even perhaps some dilute sodium carbonate (washing soda) solution. If you could get hold of some litmus paper you could check that all is neutral (the children's Chemistry teacher would, I am sure, be only to willing to help).

If it's any consolation I emptied a battery into the bilges 24 years ago and dealt with it as outlined above with no long term problems. I still have the boat!

 

[clyst]

Cheers for that VICS!!
That eases my mind and thanks to you all for your help. Now for the real confession---------It wasn't my boat it was my friend's who asked a favour of me to get the boat ready for winter storage during his bout of illness!! didn't have the heart to tell him until I was sure no lasting damage was done.mmmmmm to be honest I'm not sure I would have confessed to him anyway.

fair winds to you all

Terry

 

[1114C]

Not that it is any comfort but things could have been worse - laying up this season I took an old battery home in the back of the car and I now am the proud owner of a Volvo with almost no back seat

Car seats not as resisitant as hulls it seems!

 

[steffen]

Hi Vic, Can you elucidate on that part of chlorine forming please.
First you say that sulphuric acid with salt forms hydorgen chloride, bu tin the next line you say that when acid is contaminated with salt it does form chlorine.

I am not trying to (dont know the proper word) you but i really want to know having heard the horror stories of WWII submariners.

Happy sailings, Steffen

 

[bedouin]

I think if you get chloride ions into a battery then chlorine gas will be given off when you charge it.

 

[Spacewaist]

What about the keel bolts...?

Dunno if a Folk Song has them, or if so what they are made of, but 6 days in a 25% acid solution will have been a challenge for most metals.

 

[clyst]

Steffen.
To pasify(if thats the right spelling) the chemists, after soaking up the acid with various rags and stout rubber gloves (Sha'nt tell you where that went) sea water was bucketed into the keel sump . I was in close proximity at the time and there did n't seem to be any gasses given off but the sump was spotless!! I can only assume that I did a good job in cleaning up the area prior to dousing with water. Any way sha'nt do it again!!

regards Terry

 

[VicS]

Re: Chlorine

Yes I think this is probably the answer. The lead IV oxide in a battery is a very strong oxidising agent but I think the temperature needs to be raised before chlorine is poduced by oxidation of (hydrogen) chloride by this route. I'm afraid I'm no longer in a position to experiment to find out, but certainly electrolysis of sodium chloride solution produces chlorine at the anode, as any pupil paying attention in his or her science lessons will know.

<P ID="edit"><FONT SIZE=-1>Edited by VicS on 24/10/2002 21:34 (server time).</FONT></P>

 

[janie]

Re: Volvos

Just over a year ago, we replaced our 30 year old Volvo engine, and the old MD6 went in the back of the Volvo Estate, but on the drive home it tipped sideways and broke the window (to which the aerial is attached). Insurance replaced with a surcharge!

One week later, the mast for hauling up all the dinghy starting flags for open meetings goes from one clubhouse to the other in the same Volvo, and crazes the front windscreen. After the repairer's comments that the former break didn't look like a typical stone hitting from the outside, we waited a year before replacing the front windscreen!