NH3 purification questions???
I just went to Ace Hardware and bought professional strength non-sudsy ammonia, and it's just fine. The water in it won't hurt..
You can make your own ammonia very easily by adding a base (i.e. lye drain cleaner) to an ammonium salt (i.e. ammonium sulphate fertilizer) then bubbling the NH3 through water. The ammonia solution you get will be as pure as the water you used and you can make it as concentrated as you want.
Ace brand is 10% ammonium hydroxide, I believe it was, and it was plenty basic and pure (check the MSDS) the way it is. No need to give newbies anymore steps if they don't have to. Thanks for the chemistry tip, though!
The method of making ammonia I mentioned is somewhat dangerous (since it generates NH3 gas) and requires a bit of chemistry equipment anyway so I'd advise against it unless one has the right equipment and a bit of chemistry experience. I had a close call myself when I accidentally inhaled a significant amount of NH3 gas when I was cleaning out the reaction flask afterwards. Like Cl2 though, it will give you a fright the second you inhale a significant amount of it so it gives you adequate warning before you inhale dangerous amounts, unlike insidious gases such as CO. If in doubt about the purity of an OTC product, activated charcoal works wonders for cleaning chemicals.
I had some homemade NH3 solution lying around in the shed, I wasn't expecting it to be very concentrated but I gave it a smell and it burned my throat so it was pretty concentrated. This is the way to go in my opinion. You don't know what kind of contaminants might be in hardware store ammonia. However, with ammonia at least you can get an idea by doing an evaporation test.