8
New Liner and Plug Conditioning
New Liner and Plug Conditioning
All new liners and plugs should be conditioned as a set prior to being put into service. The break-in procedure is
used to condition the Teflon® to ensure a proper seal. CEM recommends conditioning the plugs and liners based
on the acid type that will be used.
WARNING
Proper precautions must be taken to avoid contact with acids or acid vapors. Protective gear should be
worn as outlined in the user’s safety program for hazardous materials and the acid manufacturer’s safety
data sheet. Refer to these guidelines for proper handling and disposal of the acids.
Nitric Acid Liner and Plug Conditioning
1.
Use hot soapy water and foam brush to clean the liners and plugs. Rinse thoroughly with DI water and allow to
dry completely before use.
NOTE
Micro 90 Cleaner® liquid detergent works well on Teflon. Avoid detergents that contain ingredients that
could cause potential contamination such as Na and P. Avoid abrasive cleansers and stiff brushes which
can scratch the Teflon surface.
2.
Place 0.25 g ± 0.05 g
of tea leaves or appropriate sample into each liner. Never add sample or liquid to liner
with sleeve in place.
3.
Add 10 mL of HNO
3
to each liner. Use the acid to rinse the inside of the liner to ensure that the sample is in
the base of the liner.
4.
Wait 15 minutes to allow pre-digestion.
5.
Assemble and torque each vessel. See “Vessel Assembly” for detailed instructions.
6.
Select and load the “Plant Material” method from the One Touch directory.
7.
Place vessels in turntable and insert the turntable into the cavity. See “Turntable Setup” and “Vessel Distribu-
tion” for detailed instructions.
8.
Close the instrument door and run the preprogrammed “Plant Material” method. Verify that vessel count, type,
and position are correct. It is normal for vessels to vent during digestion.
9.
After completion of the method, permit the vessels to cool in the automated sequence until the vessels cool
for a minimum of 15 minutes.
WARNING
Allow vessels to cool for a minimum of 15 minutes before opening the microwave door.
To prevent the possibility of severe burns, ensure that gloves and protective gear as outlined in your safety
program are worn.
10.
Remove the vessel assemblies from the turntable. See “Vessel Removal” for detailed instructions.
11.
Rinse the liners and plugs with deionized water.
