1. 1.5 mL/min of 90% organic is more than most plasmas can stand. Dilute 1/4 with water aand decrease flow rate to 1 mL/min, optimize sample gas, try again.
2. Use a lower flow nebulizer and decrease the liquid flow even more.
I would not suggest a Peltier cooled systm for this, snice the melting point of TB alcohol is too high - would probably solidify.
De: PLASMACHEM-L: Analytical Chem.(ICP's, DCP's, MIP's). em nome de Julia Spraul
Enviada: ter 12/21/2010 9:59
Para: [log in to unmask]
Assunto: Tertbutyl hydroperoxide (TBHP) analysis
I searched the archives for this before posting and did not find any info there, so here's some background on a problem I'm currently trying to solve. Any suggestions of things to try are welcome! Thanks in advance!
I have samples that are ~45% tertbutyl alcohol (TBA), ~45% tertbutyl hydroperoxide (TBHP), with the balance of water and iC4s. I'm trying to analyze these samples for corrosion metals (Fe, Cr) as well as Mo, Na, and P by ICP-AES. I've previously been able to analyze 20% TBA in water with no problems, however when I try to analyze these samples at a similar dilution, the plasma-Z is exceeded and the plasma extinguishes. I have also diluted the samples in isopropanol and had the same problems. We have a Perkin Elmer 5300 DV ICP. Settings used were 1500W, Plasma gas 15 L/min, Aux 0.5 L/min, Neb 0.45 L/min. 1.2 mm quartz injector, baffled cyclonic spray chamber, Meinhard C1 neb, flow rate 1.5 mL/min (tried lowering this too, with same results). Does anyone have suggestions of maybe some better settings for this sample type?
Some other things: We also have graphite furnace and flame AAs available for use if they'd handle this sample better. And we're also investigating ways to decompose the TBHP before analysis, but the ways we've come up with interfere with the elements we're looking for.
Any suggestions would be greatly appreciated. Replies here or offline are welcome.
Julia C. Spraul
Researcher, Analytical Services, Newtown Square
Lyondell Chemical Company
3801 West Chester Pike
Newtown Square, PA 19073
Office: +1 610.359.2357
Fax: +1 610.359.2442
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