Neme - 27-12-2016 at 03:49
Few weeks ago I was trying many different ions as catalyst for luminol CL.
All in form of nitrates. The results were kind of surprising.
I found that actually not small amount of metal ions when mixed with hydrogen peroxide and luminol in sodium hydroxide give quick flash of light
before precipitate (I guess metal hydroxide) starts forming.
I guess that's the reason why is usually used ferricyanide which is stable complex and not ferric chloride or something like that. Also copper based
catalyst for luminol CL is usually in tetraamincopper(II) complex.
The surprising part was when I tried sodium cation in form of sodium nitrate, there actually was weak long-lasting glow. This gives me no sense since
sodium was present from the beginning in the sodium hydroxide. What do you think? Impurities?
Another weird thing happened when I tried lithium nitrate and achieved strong medium-lasting glow. Also potassium nitrate gave weak glow.
What are your opinions, are all my chemicals contaminated, or it possible for alkaline metals to somehow catalyze this?
Tsjerk - 27-12-2016 at 23:15
Apperently cyanide by itself can catalyze this reaction, so maybe nitrates do the same.
Neme - 28-12-2016 at 01:38
I don't think so, I tried with many nitrates e.g. Ba(NO3)2, AgNO3, NH4NO3 and it was not catalyzed at all