Re: Neutralizing acid..

roman kielich (romek@ozemail.com.au)
Tue, 4 Jul 1995 23:07:27 +1000

>I've got a simple question for any of you out there... How do I neutralize
>Sulfuric Acid (92%) or at least bring it down to a level where I can dispose
>of it without fear of destroying any life or piping? I would imagine adding
>a simple base would do the trick, but would rather hear from someone who
knows.
>
>Thanks,
>Adam

Adam,
first be very careful. It burns like hell. When you mix sulfuric acid and
water, plenty of heat is released, water can splatter. because of higher
specific gravity, ALWAYS add acid to water and stir!!! Now, when you add a
base (hydroxide) there is plenty of heat released too.
The best method of getting rid of sulfuric acid is to buy marble
(crystalline form of calcium carbonate - chalk) size around 6-10 mm. During
reaction a lot of carbon dioxide is released (like soda water or better) and
almost insoluble calcium sulfate is formed. Calcium sulfate is just plaster
of Paris or gypsum. You need large glass or plastic vessel (bucket will do).
Put some marbles, add water and SLOWLY add some acid. Mix, add... watch for
rising temperature (water can boil). Wear goggles, rubber gloves and old
clothing. Control pH with some indicators, but as long as carbon dioxide is
being released, you are on a safe side. The beauty of it is that gypsum can
be safely disposed. If you use sodium bicarbonate (used to control pH of
water in swimming pools) then there is plenty of carbon dioxide and water
soluble sodium sulfate. Wash it with plenty of water. DON'T drain acid!!! Be
carefull while diluting! Wear a protective clothing. Try small amount first,
and just in case prepare some of sodium bicarbonate solution,(to wash your
skin or eyes).
Roman
Roman Kielich (Lane Cove, NSW, Australia)
e-mail: romek@ozemail.com.au (or roman_kielich@sydpcug.org.au)
Fidonet 3:712/505 phone: 61-2-418 6971