Re: How pure is "One Shot" drain cleaner?

[The Home Scientist]

On Tuesday, January 1, 2013 4:30:09 PM UTC-5, Joe Anderson Wales, UK wrote:

Hello all, I must firstly admit that I miss the old forums:(

Anyway, does anyone have any experience with "One Shot" sulfuric acid-based drain cleaners, i.e. are there usually any dyes added or suspended carbon particles? Thanks

 

Drain cleaners use technical-grade sulfuric acid, which means no analysis is done on it, other than perhaps a rough check to make sure it's of whatever minimum concentration is listed on the label.

I've done quick analyses on various brands of drain cleaner sulfuric acid I've bought here in the US. They've ranged from about 91% or 92% sulfuric acid up to 96%+. The color has been anything from what looks like reagent-grade acid to almost black. The black or dark brown acids, as you know, appear that way because they contain colloidal carbon. That's present because concentrated sulfuric acid rips most organic compounds to shreds, with the only real end product being carbon. Carbon is inert and generally harmless, so even dark-colored acid is probably fine for most or all of what you want to do.

I'd still use reagent-grade acid if I were doing a quantitative analysis or something else that's particularly sensitive to reagent purity, but for simple syntheses, I wouldn't hesitate to use the technical-grade acid. You typically have to purify the product by recrystallization or other means anyway, so the purity of the reactants usually isn't a factor.

[Joe Anderson Wales, UK]

Ok, thanks.

In your experience, typically how concentrated was the One Shot acid, did it have a dye in it, and how much (if any) colloidal carbon was present?

Thanks

[Joe Anderson]

Bump!

[The Home Scientist]

I'm not familiar with that brand, but it really doesn't matter. Again, stuff like sulfuric acid drain cleaners uses technical-grade chemicals, and even within a brand one batch may differ significantly from another.

You might be interested in a couple of videos I did on this topic:

http://www.youtube.com/watch?v=-bweWvb0wws
http://www.youtube.com/watch?v=XEH1RG3IJtg