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GC-FID cresults to TPH mg/kg of soil samples

Posted: Wed Jan 16, 2008 7:39 am
by kankyo
Hello All,

I am analyzing the TPH of the oil contaminated soil extracted using CS2 and analyzed by GC-FID. I will be reporting my results using standard light oil as mg TPH/ kg of soil. In my analysis, I used 10 g of soil samples and extracted TPH using 50 ml of CS2, and injected 2ul in GC-FID. I now got chromatograms. I also have my calibration curve using a standard light oil.

My problem is that based on my results I don’t know to express the TPH as mg/kg of soil based on standard light oil results. Could anybody help me please. I know that this is just a simple arithmetic to most of you. I already tried to exert effort on this but still I think it doesn’t work.

In my calibration curve, I plotted the total area of GC peaks except that of CS2 and arrived at a straight line. Now, I have the total area of the chromatogram, then what steps, what formula should I used in order to get the TPH mg/kg of soil..

Thank you so much

Posted: Wed Jan 16, 2008 1:17 pm
by JGK
If your Oil STDs are (or can be) expressed in mg/mL.

Caculate extracted sample concentration (mg/mL) from calibration curve
Multiply by 50 to give sample concentration (mg/10g)
Multiply by 100 to give sample concentration in mg/kg