Sciencemadness Discussion Board

pottery grade KNO3

jamit - 18-8-2011 at 00:48

I recently purchased some potassium nitrate from a pottery supply store. :D

It burned fine with 50/50 sugar combo. However, the color of potassium nitrate is off yellow, which to me indicates that it is not pure.

My question is: what kind of impurities might be in the pottery potassium nitrate?

I guess I could purify it by recrystallization, but I wonder if anyone's purchased any pottery KNO3 and tested for purity.

Retard-3000 - 18-8-2011 at 02:26

I've bought KNO3 before that was slightly yellow, i've also had some that when dissolved in solution gave a slightly dirty yellow/brown colour. After recrystallization though i had beautiful, perfectly white crystals :D

Neil - 19-8-2011 at 05:34

Fe?

It's so easy to purify, why not? :P