glacial acetic acid

[mikem_]

We have all at one time had the need to remove calcium buildup from our tanks or equipment at one time or another.
The common practice is to use vinegar, but it takes so much time for it to dissolve the calcium.
Having been an acrylic fabricator for years, I have used glacial acetic acid in mixes to bond acrylic.
Coincidentally it is what is used to make vinegar.http://en.wikipedia.org/wiki/Acetic_acid">http://en.wikipedia.org/wiki/Acetic_acid</a>
Just a thought for any of you diy-ers. You can buy acetic acid at most Wolf camera shops. It is used in developing.

 

[kevin]

I know you say it is used to make vinegar, but is it reef-safe?

 

[mikem_]

it is water soluable, I believe the ratio is 50-1` to make vinegar....
acetic is the least acidic of the acids.... It has a very pungent smell,,, like vinegar on steroids.

 

[kevin]

Ok... I was just currious. You learn something new every day.

 

[mojo]

Vinegar is usually 3% acetic acid and 97% water; there's nothing wrong with using acetic acid in your tank. However, do make sure that if you DIY with any chemical that you're getting a very pure sample. I have no idea how they create/extract acetic acid for photographic or any other equipment, but it's possible they use some other</em> process that may yeild it non-reef safe.

Having said all that, I've used 100% acetic acid (from Flynn Scientific) to dissolve calcium from parts. I about passed out, too....

 

[cgill311]

I work in a chem lab with all sorts of concentrated acids. If you guys are using glacial (just means concentrated or 100%) acetic acid, be sure to use it in a WELL ventilated area. We only use special fume hoods in the lab when working with acids or other volatile chemicals. Also be sure to wear gloves and eye protection. I can speak from experience that any concentrated acid (even though acetic is weak compared to sulfuric, nitric, or hydrocloric) can burn your skin.

Even though it takes a long time, I'd stick with vinegar.

 

[cgill311]

mikem. wrote: it is water soluable, I believe the ratio is 50-1` to make vinegar....
acetic is the least acidic of the acids.... It has a very pungent smell,,, like vinegar on steroids.

Acetic acid is NOT the least acidic acid. It is one of the weaker commonly known acids.

 

[mikem_]

I stand corrected

 

[mikem_]

Glacial acetic acid has a freezing temp of around 65 degrees, I think it freezes solid at 62. If you get "glacial" it means 100% pure acetic, no additives.
For those of you thinking of using it to make your own vinegar .......(NO NO NO) it has to go through a fermentation process.......

 

[justonemoretank]

Hooorray for chemistry, DIY, and Reeftanks! You gotta love this hobby. Everyone make sure you have your safety goggles on!

 

[myreef]

As was stated before, use in a well ventilated area...and yes the freezing point is fairly high...as I have received a full gallon completely frozen before...took 3-4 days to thaw out.

 

[maureen]

The strength and weakness of acids simply means how much the acid donates its free proton, or hydrogen ion (H+). In the case of sulfuric acid or hydrochloric acid, there is a complete dissociation which is why it is so reactive.

HCl --> H+ + Cl-

In the case of acetic acid, however, it is considered to be a weak acid because it only partially ionizes.

CH3COOH <--> H+ + CH3COO-

The quantitative determination of a weak versus strong acid is more of a continuum than a black and white determination. That being said, acetic acid is one of the stronger "weaker" acids. It donates a lot more H+ than some of the other acids also categorized as weak.

So what does this all mean for our tanks? Well, adding enough vinegar (5% acetic acid) can certainly drop the pH in your tank, and drop it considerably. So, if adding it to the tank, do it slowly and monitor pH frequently.

As for the removal of calcium buildup, I would suggest diluting glacial acetic acid. You can certainly make it more concentrated than 5% (by mass), but I wouldn't dip any of my equipment in more than 20-30%. I would worry about the acid eating through my powerheads, etc. Remember, it's not THAT weak of an acid! If nothing else, you are protecting yourself from inhaling that pungent odor. And yes, it CAN just about knock you out!

I'll stop my science lesson, but hope this was helpful for those of you who were interested in the chemistry of the acid

 

[kevin]

Thank you for the chemistry lesson. I was waiting for you to chime in. :lol2:

 

[maureen]

He-he! At least I didn't torture you all with pKa values and buffer calculations. I'll leave that for another day

 

[goodfortune]

Interesting post...BTW, it seems that you would be better off using glacial acetic acid for removing calcium deposits from reef tank equipment and accesories than muriatic acid; muriatic acid is strongly corrosive to stainless steel.

http://www.nationaldriller.com/CDA/Archives/d67160c626197010VgnVCM100000f932a8c0____">Check out this article</a>

- Michael

 

[gwen_o_lyn]

maureen3177 wrote: He-he! At least I didn't torture you all with pKa values and buffer calculations. I'll leave that for another day

Sounds like she's teasing us. We'll have to nickname you Tom Jr if you keep this up girl!!!

 

[kevin]

She might give us midterm and final exams too

 

[gwen_o_lyn]

kj_yoda wrote: She might give us midterm and final exams too

ouch- go ahead and sign me up for summer school!! :unsure:

 

[maureen]

gwen_o_lyn wrote: ouch- go ahead and sign me up for summer school!! :unsure:

Okay okay guys!! You keep this up and I might just do that...... don't make me pull out my periodic table :thumbs:

Yes, I've officially declared myself a nerd

Have a great day everyone!!

 

[johnqx4]

The quantitative determination of a weak versus strong acid is more of a continuum than a black and white determination.

This confirms the fact: By not majoring in Chemistry, I did not miss my life's calling...:yay: