Extraction:
• If applicable add an internal standard to the sample.
• Fill an appropriate amount of solid sample material (depending on the TOC
value) into a round flask.
• Add an appropriate amount of a more polar extractant (e.g. DCM, acetone
. . . .)
• Add a small piece of activated copper sheet for desulphurization.
• Add a magnetic stir bar to the flask and close the flask with a stopper.
• Treat the raw extract for 15 min in the ultrasonic bath.
• Afterwards use a magnetic stirrer and let it stir for 12 h.
• Use a pleated filter to separate the extract from the solids. Collect the extract
separately.
• If an exhaustive extraction is required, repeat the extraction step with a
second, less polar solvent.
• Concentrate the extract to approx. 1 mL.
• Switch extract solvents from DCM to n-hexane by adding approx. 2 mL of
n-hexane to the raw extract and concentrate the sample by rotary evaporation. Repeat this procedure twice.
• Prepare a Pasteur pipette by half-filling with Na 2 SO 4 (use glass wool as
stopper at top and bottom)
• After concentration to approx. 1 mL dry the n-hexane phase over the
Na 2 SO 4 filled pipette and collect the dried extract.
Further handling:
Proceed with fractionation of the raw extract
Standard Operation Procedure SOP 4—Procedure for Fractionation
of Fossil Matter Extracts
• Prepare a 2 g silica column. Use only high-quality silica gel. Activate the
silica gel column in the oven at 200
C overnight.
• For conditioning add approx. 5 mL of n-pentane on the top of the column
and let the solvent elute through the bottom of the column. Leave the
column wet.
• Transfer the raw extract (reduced to a volume of approx. 0.5 mL) onto the
top of the column. Let the sample penetrate completely the upper silica
layers.
• Wash the empty extract vial with 0.5 mL of n-pentane and add the washing
solvent also onto the top of the column.
• Add 5 mL n-pentane on the top of the column and collect the percolating
solvent at the bottom. This is the first fraction (aliphatic hydrocarbons).
(continued)
7.1 Analyses of Fossil Matter
139
• If applicable add an internal standard to the sample.
• Fill an appropriate amount of solid sample material (depending on the TOC
value) into a round flask.
• Add an appropriate amount of a more polar extractant (e.g. DCM, acetone
. . . .)
• Add a small piece of activated copper sheet for desulphurization.
• Add a magnetic stir bar to the flask and close the flask with a stopper.
• Treat the raw extract for 15 min in the ultrasonic bath.
• Afterwards use a magnetic stirrer and let it stir for 12 h.
• Use a pleated filter to separate the extract from the solids. Collect the extract
separately.
• If an exhaustive extraction is required, repeat the extraction step with a
second, less polar solvent.
• Concentrate the extract to approx. 1 mL.
• Switch extract solvents from DCM to n-hexane by adding approx. 2 mL of
n-hexane to the raw extract and concentrate the sample by rotary evaporation. Repeat this procedure twice.
• Prepare a Pasteur pipette by half-filling with Na 2 SO 4 (use glass wool as
stopper at top and bottom)
• After concentration to approx. 1 mL dry the n-hexane phase over the
Na 2 SO 4 filled pipette and collect the dried extract.
Further handling:
Proceed with fractionation of the raw extract
Standard Operation Procedure SOP 4—Procedure for Fractionation
of Fossil Matter Extracts
• Prepare a 2 g silica column. Use only high-quality silica gel. Activate the
silica gel column in the oven at 200
C overnight.
• For conditioning add approx. 5 mL of n-pentane on the top of the column
and let the solvent elute through the bottom of the column. Leave the
column wet.
• Transfer the raw extract (reduced to a volume of approx. 0.5 mL) onto the
top of the column. Let the sample penetrate completely the upper silica
layers.
• Wash the empty extract vial with 0.5 mL of n-pentane and add the washing
solvent also onto the top of the column.
• Add 5 mL n-pentane on the top of the column and collect the percolating
solvent at the bottom. This is the first fraction (aliphatic hydrocarbons).
(continued)
7.1 Analyses of Fossil Matter
139