Quote:
Well, it is an evil chemical, but not one that is hard to get rid of.
In the warnings, it says that if you expose it to water or oxygen, it can burn. (it is in methanol, which keeps air and water away from it, guess what? Methanol burns too.)
When you add water, the byproducts are NaOH and CO2 (carbon dioxide). Ever make soap? NaOH is lye and very caustic.
I would put the containers somewhere that won't burn and would not be affected by caustic water. Then I would open them and let them dry out. Then, I would rinse them out with water, then put in some vinegar and swirl that around. If the vinegar bubbles (produces CO2) wash them out with water again. At least the first time you do this, be at least 50' away when you turn the water on.
UNDER NO CIRCUMSTANCES SHOULD YOU INHALE WHAT COMES OUT OF THEM!!!
I hope that helps.
Edited to add: I looked a little more closely at the MSDS form. The pH of a 0.5% Aq. Solution is 14. That means that it needs about a 10^7 dilution factor to be neutral (less if vinegar or battery acid are used). How to say this. . . . This stuff is bad. How bad? If you get any on you, the fastest way to neutralize it would be to pour a bunch of battery acid on yourself.
Also, the reaction causes heat and you don't want to melt the container so, don't dribble the water in, give it all the water it wants to react with, and then a bunch more water to cool everything down.
So flood with water then rinse with vinegar and if vinegar bubbles flood with water again.....?
after it is thoughly rinsed and cleaned it should be fine for water/garden/fish... right?