Product Manual for IonPac CS16
Page 15 of 65
3.12.
Using AutoRegen
®
with the Chemical Suppression Mode
Dionex recommends using an AutoRegen Accessory (P/N 039594) with eluents that do not contain acetonitrile.
It
should be used with the CMMS 300. The AutoRegen Accessory saves regenerant preparation time and reduces regenerant
consumption and waste.
Acetonitrile is not compatible with the AutoRegen Cation Regenerant Cartridge. The acetonitrile diffuses
into the TBAOH regenerant, concentrates during recirculation and eventually hydrolyzes to acetate and
ammonia, depleting the capacity of the AutoRegen Cation Regenerant Cartridge. If acetonitrile is used with
suppressed conductivity, a pressurized vessel rather than the AutoRegen must be used.
CAUTION
!
When using an AutoRegen System, the regenerant passes over the hydroxide form anion exchange resin in the AutoRegen
Cation Regenerant Cartridge where specific anionic contaminants (such as chloride ions) are continuously removed from the
regenerant (TBAOH) to restore the salt form of the regenerant to the base form. If solvents are used in the eluent, ionic
contaminants from the solvent component of the eluent which are not removed by the AutoRegen Regenerant Cartridge
slowly accumulate in the regenerant. This results in slowly increasing background conductivity. The rate at which the
background conductivity increases versus the required analysis sensitivity will determine how often the regenerant must be
changed. It is not necessary to change the AutoRegen Regenerant Cartridge until it is completely expended.
Use Dionex Cation Regenerant Solution (TBAOH, 0.1 M tetrabutylammonium hydroxide, P/N 039602). This ensures
maximum system performance. If you are using the AutoRegen Accessory (P/N 039594) equipped with an AutoRegen
Cation Regenerant Cartridge (P/N 039563), prepare 0.5 to 1.0 liter of the regenerant. If you plan to use a pressurized vessel,
prepare several liters.
Equilibrate the AutoRegen Cation Regenerant Cartridge to new regenerant. When replacing the recycled regenerant, the first
200 mL of the regenerant should be pumped to waste before recycling of the regenerant is started. Utilizing AutoRegen in
this manner will allow the use of high regenerant flow rates with the minimum of consumption and waste.
Increase the regenerant flow rate for gradient analysis. To minimize the baseline shift when performing an analysis that
requires a H
2
SO
4
or methanesulfonic acid step or linear gradient, a high regenerant flow rate (10–15 mL/min) is required.
3.13.
Detector Requirements
See Section 2, “The 5-mm and 3-mm Ion Chromatography System,” system detector, cell and thermal stabilizer
requirements.
Document No. 031747-05
© 2010 Dionex Corporation
December 2010
