Can someone give me the chemical reaction (byproducts) when using baking soda to neutralize a weak sulfuric acid solution?  I want to change out my old anodizing bath and am too lazy to open up the old chem book.

I'm a Chemical Engineer will that do?  Look here at the bottom of the page you'll see the reaction.  [url]http://www.chem.umn.edu/services/lecturedemo/info/EndothermicRXN.html[/url]You'll make a lot of CO2 gas and sodium sulfate (a harmless salt that will be invisibly dissolved in the remaining solution).  This is the same thing that happens when one neutralizes battery acid.  Add the bicarbonate very slowy to avoid foaming over.  Wear lots of protective gear against splashing.  When there's no more CO2 coming off add more Bicarb to be safe then you should be able to safely dispose of the now harmless solution.  Here's more tips. [url]http://www.ncnr.nist.gov/safety/acid.html[/url]  You may want to dissolve some of the Bicarb in water before adding to avoid the foaming reaction.   The more dilution you can do the safer.  Add the reagents together in very small quantities and very cautiously to avoid splashing reations (e.g. foaming).  

As an organic chemist I agree with MOnkeyGrip...sounds like a good safe plan.

Like the others mentioned, it should be all right.  It might get a little exothermic…[:D]


Sloth…… Organic chemistry…. Sweet![bounce] The company I work for specializes in Organic chemistry.
We work with a LOT of chlorosilanes!

Monkeygrip mentions diluting the sodium bicarbinate... NEVER add water to acid.  The water immediately heats up and boils, splattering all over, or even exploding.  Always add acid to water.

Wear goggles AND a face shield, rubber apron, if you have one, a slicker suit is better.  long rubber gloves.  Make sure the area is well ventilated.

Have a helper nearby, but not close enough to get splattered, with a running water hose in hand ready to hose you down in case of an accident.

But what do I know, I screw with this stuff almost daily.

Hehe..... You ever seen water thrown on a large spill of Oleum (Sulfuric Acid w/Sulfur Trioxide)heehee![peep]

A comes before W, allways add Acid to Water...

Yeah, they're right.  In fact, you'ld probably be better off doing the neutralization in a separate (very large) vessel, adding portions of the acidic solution little by little to a strong solution of the bicarb.  

Keep in mind that (in the worst case) if you do get sufuric acid in your eyes DON'T PANIC wash it out fast and you should be OK.  Keep a hose or lots of water nearby.  From what I've read, you've only got a 25% solution which is a little less than battery acid.  I've heard of mechanics getting battery acid in the eyes (often) and (in one incedent) he douched it out with a Coke and was fine  (Chemical war stories).  I myself was sprayed with 66 Baume (93%) sulfuric acid at a Pulp Mill I was working at.  It instantly burned holes in my jacket and burned my eye a bit but I washed it out in a nearby sink.  I miss those hands-on days.  

Thanks for the tips.  I neutralized 3 gal of 33% battery acid/water this afternoon.  I could not believe how much baking soda it took... at least 10 lbs?!?!?!  Maybe I went too fast or something... its really sludgey now.

Anyway, it sounds like everything is now drain safe?

Good job.  Way to manhandle it.  
 As far as I know the sludge is just excess sodium bicarbonate, and the remaining junk is just water, sodium sulfate and excess bicarb.  Which sounds OK to dump to me.  Anybody else have a thought?

How long will it take until we see the first story...


..."Well, I ran out of tannerite, but I had some H2O2 and an old car battery...."


I would say to decant and dump liquid drown drain.  Solid will probably cake up when it dries--toss it in trash.

Whew dude you're lucky! I have to unload tanker trucks of this mess...... Nothing like dressed in a full acid suit in 90 degree florida weather!

Winter time ain't so bad but the summer months suck!

Ya know, looking back on how much Bicarbonate it took, you could have neutralized the whole mess with very little Red Devil Lye, which I've bought and used for making soap.