What's the best procedure for making salicylic acid?

Is it possible to make salicylic acid from aspirin using pretty common household gear? 

If not, what would be the procedure for deriving it from willow? and what kind of willow to use? 

Would it be more cost effective to buy crystalline salicylic acid? 

Bonus Question:  What ppm would be good for using it as a facial cleanser and an anti-dandruff shampoo? or rather, what ppm would be bad?

If it matters, I've done a year of chemistry and a year of organic chemistry with labs.  I sucked at the classes but rocked the labs like KISS at an assisted-living activity day.

 

Comments

[makendo]

Yes, buying it is greener: ASA is made from SA anyway, so if you were to extract ASA from aspirin, then hydrolyze it to SA, you've wasted a lot of reagents and solvents for nothing. Good info for your app here:
personalformulator.com/wvss/product_info.php

[AngryRedhead]

YAAAAY!!!!  I could not find a source for it.  Great site.

And ya, I've made aspirin before in an organic chem lab.  Absolutely horrific yield if I remember correctly.  I think I got a 3% yield or worse.  lol

 

[rncbme]

Salicylic acid is the main ingredient in "Bar Keeper's Friend" and also most wood bleaches (Lowes, Home Depot, etc). It is obtainable in much larger quantities than what most people would think about making w/aspirin.

[lemonie]

It's not going to be hard to obtain from Aspirin - but you've got the product to purify afterwards. Possible yes, but if you can buy it that would be easier.

The skin-destroying formulations for wart-removal are ~ 10% w/v, so you'd want much less than that or a short exposure.

DIY acid-peel?

L

[AngryRedhead]

Oh my god, no, not a DIY acid-peel.  Just facial cleanser and anti-dandruff shampoo since salicylic acid is the typical active ingredient in both (or at least in the ones that I like).

Buying it would most definitely be easier.

 

[lemonie]

It's a pretty-strong phenolic acid, but I didn't know it was in those things. Start it below 0.01% w/v and knock it up an order of magnitude at a time if you don't think it's enough?

L

[AngryRedhead]

The anti-dandruff shampoo I like best is 1.8% salicylic acid.  You can buy pimple creams from 2-5% I believe.  Beyond that you're getting into prescription levels of it, I think.  I suspect it's because you use water and don't leave it on for any great length of time because it's all washes and soaps.  I keep a bottle of hydrogen peroxide by the tub (for cleaning ears), so maybe if something went horribly wrong, I could douse myself in it.  I doubt I'd need to though, but it's always good to have an emergency plan, right?

 

[lemonie]

Bi-carb' rather than peroxide I think. I didn't know the 'poo was that much, but I'm learning here...

L

[AngryRedhead]

Funny you should mention bicarb because it often seems I also have a big box of baking soda in the bathroom too.  It's great for household cleaning and unclogging semi-clogged drains (obviously with a bit of vinegar too).

Salicylic acid is pretty amazing stuff, and it helps with a lot of different skin conditions.

 

[Burf]

http://www.crscientific.com/article-aspirin.html

[AngryRedhead]

Ha!  I knew it!  It seems I can buy it for pretty cheap though.