Determination of benzene in fuel by EN12177

[bublle]

How to handle with isobuthylmethyl ketone and other reagents?
When I try to prepare a calibration sample, I can't weight accuratly the mass of IBMK due to it's evaporation.
(weight decreases on and on...) All that makes my benzen determination no quite accuerate!!!!!!!
Should I make everything cold,like iBMK, flask, nC7, vial???

Thanx,
bublle

[chromatographer1]

Not all of us have access to the method EN12177. Can you describe the std you wish to prepare? unless you only wish they who have the method to advise you. Thanks.

Rod

[Peter Apps]

Hi Bublle

Using septa on containers reduces bias and variability:

APPS, P.J. and ARCHER, M. 2010. Evaluation of the source of bias caused by losses of solvent vapour during sample preparation. Journal of Accreditation and Quality Control 15: 171–180.

There was some good discussion on handling voaltile solvents a while ago, try a search of the forum and the archives.

Peter

[Beetle Juice]

When I prepare standards of volatile compounds e.g. MIBK. I find extracting a certain volume using a glass/gas syringe and then working out the mass taken from the density (D=m/v)much more reproducible than weighing it out.