One of our customer is carrying out NAPTHA Analysis using UltraSonic
Nebuliser . I hope you might have tried that . They are doing As
analysis but I am not sure about Hg .
ALL INDIA MANAGER ( Service Division)
ADVANCE SCIENTIFIC EQUIPMENT PVT LTD.
Ghatkopar , Mumbai -400086 .
email : [log in to unmask]
Mo: 91-9323973276 / 9967079393.
LL : 022-25002632 .
From: PLASMACHEM-L: Analytical Chem.(ICP's, DCP's, MIP's).
[mailto:[log in to unmask]] On Behalf Of (Geoff Tyler)
Sent: Monday, January 04, 2010 10:00 PM
To: [log in to unmask]
Subject: digestion method of naphtha for sub ppb Hg determination (by
I have a puzzle that hopefully someone can help me.
We have a need to determine sub ppb (ug/L in solution) of Hg in naphtha
While the peltier cooled Spray chamber on the ICP-OES will get us to
about 5 ppb Hg, we need to think of digestion & pre-concentrate for
aqueous hydride generation Hg determination to achieve the goal of sub
ppb LOQ. (so the LOD needs to be < 0.2ppb).
I have thoughts of conc HNO3 attack on neat naphtha & then careful
pre-concentration. I can see of sorts of problems like:
1 Would Conc HNO3 digest all the naphtha?
2 How to pre-concentrate the digested aqueous solution, without
loss of Hg
maybe a closed vessel microwave oven will solve that ?
3 How to ensure oxiding state is not too strong to prevent NaBH4
(or SnCl2) reduction to enable reduction to Hg vapour.
There is insufficient need to justify a specific low level Hg analyser
in petroleum ( like that supplied by PSA )