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Specialty Chemistry Forums => Citizen Chemist => Topic started by: Giles87 on May 18, 2018, 07:11:23 PM

Title: Buffered Sulfuric Acid Dangers
Post by: Giles87 on May 18, 2018, 07:11:23 PM
Is it possible for buffered sulfuric acid to remain on a surface and not cause any damage, specifically finished/sealed wood, tile, acrylic interior paint, plastics?

If yes, will the acid remain wet indefinitely and still be capable of burning someone if touched months later?

If no, will the acid eventually dry and become inert or evaporate?

I believe it is a 93% buffered sulfuric acid; details from the label are below:

PH: Less than 1 (1% AQUEOUS SOLUTION)
BOILING POINT: 235 degrees F
SPECIFIC GRAVITY (H2O=1): 1.240 TO 1.280
VAPOR PRESSURE (mm Hg): 1.7mm 250 degrees F VAPOR DENSITY (AIR=1): less than 1.0 MMHg at 100 degrees F
SOLUBILITY IN WATER: Complete
PERCENT VOLATILE (BY WEIGHT): 7% EVAPORATION RATE (EITHER=1): Less than 1.0 WEIGHT/GALLON: 16.00 LB
APPEARANCE: Clear to dark brown with no odor

Thanks
Title: Re: Buffered Sulfuric Acid Dangers
Post by: Borek on May 19, 2018, 03:41:06 AM
Chances are some plastics and some finishings will survive. Initially it will absorb water from the air getting a bit diluted, but eventually it will dry out.
Title: Re: Buffered Sulfuric Acid Dangers
Post by: Arkcon on May 19, 2018, 10:06:18 AM
I really don't understand what buffered means when describing concentrated sulfuric acid, or if this is delivered as a concentrate, with a buffering agent,that is then diluted and used.

This has come up on our forum before, and I really don't know the layman's solution to a spill on the floor.  Sulfuric acid isn't going to evaporate when dried and Borek: has described how it will stay in equilibrium with the ambient humidity as a strong solution of sulfuric acid, which is at least a little bit hazardous.

But it can't float like a bead of mercury on a surface forever, either.  Eventually, it will react with most surface coatings, reacting with and damaging them and eventually soaking into a porous surface somehow.

In the lab, when I have sulfuric acid, that I for some reason don't want anymore, I dilute it with water and neutralize with a weak base like sodium carbonate.  And floor spills get cleaned up in the lab in that way. 
Title: Re: Buffered Sulfuric Acid Dangers
Post by: Giles87 on November 12, 2018, 08:19:34 PM
Thank you for your replies. Wanted to follow-up on this.

Is it possible if any sulfuric acid splattered on something, i.e. finished wood, leather furniture, painted walls with latex paint, plastic/metal electronics, etc. and wasn’t wiped down with water that it could still be “live” and capable of burning someone if touched?

For anyone wondering, the acid listed above was a heavy duty drain cleaner. After the plumber used it he set up fans to air the place out. He walked through the area with the acid’s plastic bottle and we’re worried some may have splashed on furnishings and things not easily cleaned.

This happened about nine (9) months ago so we were wondering if any acid might be dry by now if it didn’t destroy a surface it came into contact with initially or if it could still be wet and dangerous if on plastic or similar surface it couldn’t burn.

Are we worrying for nothing?

Thank you!
Title: Re: Buffered Sulfuric Acid Dangers
Post by: Borek on November 13, 2018, 02:56:11 AM
Are we worrying for nothing?

After nine months? Yes.