Buchi SpeedExtractor E-914, Operation Manual

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6 Operation
47
SpeedExtractor E-916 / E-916XL / E-914 Operation Manual
Alternatively, use a paper or glass fiber thimble to fill in your sample. The thimbles are recommended
for polymers and plastics (samples with tendency to melt during the extraction process) and sticky
samples, when not mixed with sand or diatomaceous earth. They are specially recommended for
the method development of the mentioned sample types. Glass fiber thimbles are beneficial for
gravimetric and residue determinations (lower blank value than paper thimbles).
NOTE
Close the plug screws hand tight. Over tightening the plugs can damage the cell. They are not
used to seal the cell but only to fix the filter and frit in place.
B
Insertion of the sample
Turn back the cell to its “regular” orientation (the frit is
now at the bottom) and insert the metal funnel
e
into
the offset of the cell (or the graduated line for the largest
cells; 40 mL for the E-916 , 60 mL for E-916XL and 120 mL
for the E-914). It is recommended to place the cells into
the cell rack for sample loading (E-916: P/N 053690;
E-916XL: P/N 11069547; E-914: P/N 053691) to provide
more stability.
In order to carefully load the sample into the cell using
the optional weighing boat
f
(P/N 053202). Rinse the
weighing boat with some additional sand. If desired, fill
any cell void volume with additional sand or, in the case
of the 10 mL cells, use the optional expansion element,
2 mL (P/N 053355) to reduce the amount of solvent for
extraction.
Alternatively, use a paper or glass fiber thimble to load your sample. The use of thimbles is recom-
mended for polymer samples and plastics with tendency to melt during the extraction process and
sticky samples, when not mixed with sand or diatomaceous earth. In particular they are recom-
mended for method development in case of complex sample types. Glass fiber thimbles are benefi-
cial for gravimetric and residue determinations with impact on lower blank value than paper thimbles.
NOTE
It is important not to fill the cell completely but to retain a void approx. 0.5 – 1 cm in height between
the sample bed and the upper filter. This prevents the sample from clogging in case of swelling
and thereby guarantees uniform flow.
Differently packed extraction cells usually require different amounts of solvent, because the dead
volume and back pressure are different.
e
f