What Ratio of Peracetic acid?

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paz1
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What Ratio of Peracetic acid?

Post by paz1 » Fri Dec 02, 2011 4:47 pm

Hi,

I am being very thick here, but can some please spell it out for me. I have read several post regarding the ratio of dilution of Peracetic Acid, but I am still just as confused as before reading them. I can not get my head round the figures of making up x% solution.

Can someone please provide me a ratio for how many mls of Peracetic acid (5%) I add to 1 litre of water. Any help will be greatly appreciated.

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Kev888
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Re: What Ratio of Peracetic acid?

Post by Kev888 » Fri Dec 02, 2011 7:23 pm

I have some 5% solution from the Malt Miller (though I just noticed it seems to have disappeared from his site..). It suggests a rate of 3-to-5ml added to 250ml of water, so that would equate to 12-to-20ml added to 1L of water. To be honest, I just went with that suggested ratio and haven't bothered to calculate what it means in terms of 'actual' dose, but here goes:

20ml of 5% peracetic in 1000ml = 2ml in 100ml, but the solution is only 5% to begin with, so the actual amount of peracetic acid is 5% of 2ml = 0.1ml in 100ml, or 0.1% If you wanted to make about 250ml or so at a strength of 0.1%, then the quantity of acid needed is about 250 x 0.1 / 100 = 0.25ml. But the original mix is only 5% acid, so 0.25ml is only 5% of what must actually be added; the total (100%) of whats needed would be 100 / 5 x 0.25 = 5ml

At least that 'seems' right.. As I mentioned I've not worked it out before so anyone able to confirm that this is about right would be most welcome..

Cheers
kev
Last edited by Kev888 on Thu Feb 14, 2013 9:51 pm, edited 1 time in total.
Kev

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paz1
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Re: What Ratio of Peracetic acid?

Post by paz1 » Fri Dec 02, 2011 9:19 pm

Thanks Kev, thats really helpful. Thanks alot.

I was going crazy thinking will I burn my hands or will I leave the equipment unsanitiased.

Having followed your equation through, it also makes sense and seems logical.

Thanks once again.

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