Waters 2414 - Page 94

June 11, 2015, 715004754 Rev. A
Page 94
Required tools and materials
• A wrench suitable for removing and replacing the column
• A solvent miscible in both the mobile phase and water (methanol is commonly
used)
•HPLC-grade water
• A strong cleaning solvent suitable for your system (6N nitric acid is commonly
used)
• A separate waste container for acid waste
• If you use an acid as a cleaning solvent, a means of measuring the pH of the
acid effluent
Requirement: If you use 6N nitric acid and operate the detector at high
sensitivities, flush the system extensively with water to remove all traces of the acid.
Avoid flushing nitric acid through the reference flow cell.
To decontaminate the fluid path:
Requirement: Strictly adhere to the following procedure.
1. Stop the pump or solvent delivery system, and replace the column with a union.
2. Replace the mobile phase with an intermediary solvent miscible in both the
current solvent and water.
3. Set the detector to purge mode for approximately 5 minutes, and operate it for
an additional 5 minutes in normal mode.
4. Restart the pump or solvent delivery system, and then set the flow rate to
5 mL/min, maintaining the purge for at least 5 minutes.
5. Switch the pump or solvent delivery system to HPLC-grade water, and flush the
detector for 10 minutes.
6. Switch the pump or solvent delivery system to the cleaning solvent, and flush
the detector for 10 minutes.
7. Switch the pump or solvent delivery system back to HPLC-grade water and flush
until the pH of the waste effluent is neutral (a pH value of 6.0 to 7.0).
8. Switch the pump or solvent delivery system back to the water-miscible
intermediate solvent, and flush for 10 minutes.
9. Switch the pump or solvent delivery system back to the mobile phase, and flush
for 5 minutes.
10. Disengage the purge mode, and stop the pump or solvent delivery system.
11. Reattach the column and reequilibrate the detector.
Warning: Strictly adhere to the following procedure.
Warning: Provide a separate, clean, waste container for the cleaning
solution. Do not allow organic waste to mix with acid waste.