1
– Introduction
Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 10 of 84
031956-11
For Research Use Only. Not for Use in Diagnostic Procedures.
Figure 1
The Electrolytically Regenerated Suppressor and Accessories
Tip
For assistance, contact Technical Support for Dionex Products. In the U.S., call 1-800-
346-6390. Outside the U.S., call the nearest Thermo Fisher Scientific office.
The Dionex ERS 500 design comprises of three channels defined by two ion exchange
membranes. The central channel is the eluent channel and the two side channels are regenerant
channels. Two PEEK plates form the outer wall of the regenerant channels and have ¼-24 ports
for bringing in the regenerant liquid into and out of the device. The eluent channel is physically
defined by a PEEK plate that seals against the ion exchange membrane and a thin elastomeric
O-ring installed in the regenerant channel. The eluent in and out ports are independent ports that
define the fluidic pathway, similar to a column. The regenerant flow is arranged to be counter-
current to the eluent flow. This orientation ensures complete regeneration of the device
Electrodes are placed along the length of the regenerant channels to completely cover the eluent
channel. In operation, when a DC voltage is applied across the electrodes and the voltage
exceeds the standard potential for the electrolysis of water (approximately 1.5 V), water is
electrolytically split to form electrolysis ions.
At the anode
H
2
O
2H
+
+ 1/2O
2
+ 2e
-
At the cathode
H
2
O + 2e
-
2OH
-
+ H
2
The electrolysis ions are then available for the suppression reactions. The Dionex ERS 500
suppressor design allows facile transport of cations or anions depending on which type of
suppressor is used for the application. For example, when pursuing anion analysis with a Dionex
Dionex ERS 500 Suppressor
Backpressure Coils
1/8 in. o.d. tubing
Gas Separator Tube
Waste Container
