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Appendix C
5/20/2009
21
12.2.1.18 JT Baker PN 1820-01 Cupric Oxide
Wire, Baker Analyzed, A.C.S. Reagent grade or
equivalent.
12.2.2 Make sure oven is off and cooled to room temperature.
12.2.3 Remove the old column by unscrewing the two side screws
on the mounting plate.
12.2.4 Remove the injection port slide, and the injection block.
12.2.5 Release the TC gas line from the side of the block.
12.2.6 Remove the syringe from under the 4 port valve.
12.2.7 Rinse the syringe and replace the old plunger and tip with a
new plunger and tip.
12.2.8 Remove the old mist trap filter ball and replace with a new
filter, taking care not to touch with bare fingers.
12.2.9 Remove the ultra pure water trap, rinse well, and return.
There is no need to fill with water.
12.2.10 The catalyst and the cupric oxide may be used straight
from the bottle, but it is recommended that each be pre-
combusted between 680
°
and 850
°
C for 90 minutes. This
reduces the time needed to condition the column. Left over
pre-combusted catalyst and cupric oxide may be stored in a
desiccator.
12.2.11 Place 2 platinum screens in the bottom of the column.
Cover with a very thin layer of quartz wool. Note:
pressure problems may arise if the quartz wool is too thick.
12.2.12 Pour 120 mm of catalyst into the tube. Top with 2-4 mm of
cupric oxide. Note: The CuO is used to prevent back
splashing of the vaporized sample, which causes doublet
peaks.
12.2.13 Smear a thin layer of high vacuum silicone grease 1-2 mm
below the top of the column. Set aside.
12.2.14 Remove the old orings from the top of the injection block.
Rinse the block. Put a thin layer of silicone grease on the
new black oring and put into place. Lay a new (white)
Teflon oring on top. Do not grease. Note: the Teflon
coated oring on the underside of the injection block needs
to be replaced twice yearly.
12.2.15 Remove the injection needle from the injection slide.
Rinse the slide, Replace with a new needle (remove the
wire from inside the new needle). Adjust the needle so that
only a millimeter or so is showing through the slide, and
then tighten the knurled nut. The tip of the needle should
not be visible when holding the slide on a horizontal plane.
It will score the Teflon oring if it is out too far.
12.2.16 Slide the air tubing back onto the needle.
12.2.17 Insert the column into the bottom of the injection block.
Place into the furnace opening, making sure that the drain