aa1ss1 - 23-2-2011 at 12:41
Sorry if this not right place for this question .
My question is.
Can we measure formaldehyde and acetaldehyde in ethylene oxide product by gas chromatography?
If it's can please, i need this method.
thank to all
Ozone - 23-2-2011 at 13:41
Not that I know of. There are two HPLC methods, however, that might work, The first EPA 8315 involves sparging gas through a buffered (citrate pH 4.5
or acetate 5.0 at 1M) solution of dinitrophenylhydrazine (DNPH), extraction with DCM, concentration and analysis via HPLC (C18, VIS 360nm). This is a
no-go (depending upon gas concentration) because the EO rings will hydrolize to give ethylene glycol (chemically it's ok, but it will create handling
problems).
The other, EPA TO-11, based upon a bound LpDNPH (supelco) cartridge would be more practical (meter gas through the cartridge, flush out remaining EO
with inert gas and elute with a minimal amount of, say, acetonitrile and chromatograph as given below.
HPLC:
A = AcCN:THF:water 30:10:60
B = AcCN:water 60:40
0% B for 1 min then a linear gradient to 100% B over 10 min. Flow = 1.5 mL/min.
Inject = 25 uL
See: Supelco (2007-2008). Chromatography Products for Analysis & Purification. Air monitoring applications, pp. 476.
Cheers,
O3