I don't use ICP-OES, but 100 ug/L sounds like a huge concentration to
me, and that in acid solution, it is asking to complex with anything
poorly soluble that may also have been left around from your previous
analyses in the introduction system, like maybe Fe(III), or even a
divalent ion at huge concentration. You most likely have Sb in V
oxidation state as its oxoacid in acidic solution. This would indeed be
chelated well by tartrate, fluoride, or oxalate, but don't use oxalate,
because it will precipitate lead and some other divalent ion salts and
complexes, and don't use fluoride, or you will precipitate high calcium
and magnesium concentrations. - It sounds like your "base metal mine
wastewater" is loaded with metals, if you don't mine me saying so. I
hope I was not off base with that assumption. At 1000 ppm dissolved
solids, you may have to add a lot of chelator before it scavenges up all
the metals it can scavenge, that are at higher concentrations still.
Maybe youwater try diluting first so the tartrate addition won't be a
R. Steven Pappas, Ph.D.
Emergency Response & Air Toxicants Branch
Centers for Disease Control & Prevention
4770 Buford Hwy. NE, M.S. F-44
Atlanta, GA 30341-3717
[log in to unmask]
From: PLASMACHEM-L: Analytical Chem.(ICP's, DCP's, MIP's).
[mailto:[log in to unmask]] On Behalf Of Gerry Grady
Sent: Tuesday, January 19, 2010 4:43 PM
To: [log in to unmask]
Subject: Sb Antimony carryover in ICP-OES
I have an application query from a customer lab regarding unusual
behaviour of Antimony in ICP-OES analysis.
In summary it appears that Antimony exhibits carryover when in simple
Sample & Standard matrices (e.g. 1%HNO3), but washes out quickly & has
excellent RSD's in a more complex sample solution (in this case a
wastewater sample from a base metal mine with about 1000ppm dissolved
Sb concentrations are in the region of 100 ug/L.
I have heard that adding tartaric acid is the key to solving this Sb
stability/ mobility problem, but would welcome any specific advice.
Instrument is a Varian 720 AX.
Many thanks for an comment!
Varian ICP Sales
JVA Analytical Ltd