MeshPL
Hazard to Others
Posts: 329
Registered: 20-4-2015
Location: Universe
Member Is Offline
Mood: No Mood
|
|
Test for nitrite
Hello everybody!
I was wondering if any of you know a good test to detect small amount of nitrites in presence of:
-some alcohol (traces)
-a lot of nitrates
-little fluoride
-some metal ions (Pb, Cu, Ni, little Na)
-highly acidic pH (around 1)
Thre were some nice tests, like thiourea + iron (III), sulphamic acid + barium, azo coupling, indole nitrosylation but I'm not sure if they will be
good for those conditions. Also indole or reagents for azo coupling are hard to get.
[Edited on 23-2-2016 by MeshPL]
|
|
|
UC235
National Hazard
Posts: 565
Registered: 28-12-2014
Member Is Offline
Mood: No Mood
|
|
Nitrous acid has a pKa of 3.4 so anything more acidic than that is going to get you HONO from nitrites and it decomposes quite readily.
|
|
|
MeshPL
Hazard to Others
Posts: 329
Registered: 20-4-2015
Location: Universe
Member Is Offline
Mood: No Mood
|
|
Yea, but I'm pretty sure traces will remain I think, and I want to detect those traces.
Unless, you say, that there will be no detectable traces, than I may give that up.
|
|
|
nezza
Hazard to Others
Posts: 324
Registered: 17-4-2011
Location: UK
Member Is Offline
Mood: phosphorescent
|
|
Azo coupling should work and is likely to be quick, easy and sensitive.
If you're not part of the solution, you're part of the precipitate.
|
|
|
woelen
Super Administrator
Posts: 7985
Registered: 20-8-2005
Location: Netherlands
Member Is Online
Mood: interested
|
|
Add some thiocyanate salt. You obtain some nitrosyl thiocyanate, which is very dark brown in aqueous solution and slowly decomposes. This reaction is
quite sensitive.
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
