Thermo Scientific Dionex ERS 500 User manual

For Research Use Only. Not for Use in Diagnostic Procedures.
Dionex ERS 500 Suppressor
031956 Revision 11 •January 2017
User Manual

Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 2 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
Product Manual
for
Dionex Anion Electrolytically Regenerated Suppressor 500
(Dionex AERS 500 (4 mm), Item # 082540)
(Dionex AERS 500 (2 mm), Item # 082541)
Dionex Cation Electrolytically Regenerated Suppressor 500
(Dionex CERS 500 (4 mm), Item # 082542)
(Dionex CERS 500 (2 mm), Item # 082543)
Dionex Anion Electrolytically Regenerated Suppressor 500e
(Dionex AERS 500e (4 mm), Item # 302661)
(Dionex AERS 500e (2 mm), Item # 302662)
Dionex Cation Electrolytically Regenerated Suppressor 500e
(Dionex CERS 500e (4 mm), Item # 302663)(Dionex CERS 500e (2 mm), Item # 302664)
Dionex Anion Electrolytically Regenerated Suppressor 500 for
Carbonate Eluents
(Dionex AERS 500 Carbonate (4 mm), Item # 085029)
(Dionex AERS 500 Carbonate (2 mm), Item # 085028)

Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 3 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
© 2017 Thermo Fisher Scientific Inc. All rights reserved.
MASTERFLEX C/L is a registered trademark of Barnant Company. All other trademarks are the property of
Thermo Fisher Scientific Inc. and its subsidiaries.
Thermo Fisher Scientific Inc. provides this document to its customers with a product purchase to use in the product
operation. This document is copyright protected and any reproduction of the whole or any part of this document is
strictly prohibited, except with the written authorization of Thermo Fisher Scientific Inc.
The contents of this document are subject to change without notice. All technical information in this document is for
reference purposes only. System configurations and specifications in this document supersede all previous
information received by the purchaser.
Thermo Fisher Scientific Inc. makes no representations that this document is complete, accurate or error free and
assumes no responsibility and will not be liable for any errors, omissions, damage or loss that might result from any
use of this document, even if the information in the document is followed properly.
This document is not part of any sales contract between Thermo Fisher Scientific Inc. and a purchaser. This
document shall in no way govern or modify any Terms and Conditions of Sale, which Terms and Conditions of Sale
shall govern all conflicting information between the two documents.
Revision History:
Revision 08, April 24, 2013, Rebranded for Thermo Scientific. Product name changed from Dionex SRS 300 to
Dionex ERS 500.
Revision 09, November, 2013, Updated External Water Mode flow rate recommendations, Updated hydration
procedure.
Revision 10, August, 2015, Added support for the Neutralization mode. Added support for Carbonate Eluents.
Revision 11, January, 2017, Updated the recommended suppressor hydration procedure. Edited for length and
clarity. Added Dionex ERS 500e product.

Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 4 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
Safety and Special Notices
Make sure you follow the precautionary statements presented in this guide. The safety and
other special notices appear in boxes.
Safety and special notices include the following:
Indicates a potentially hazardous situation which, if not avoided, could result in death or
serious injury.
Indicates a potentially hazardous situation which, if not avoided, could result in damage to
equipment.
Indicates a potentially hazardous situation which, if not avoided, may result in minor or
moderate injury. Also used to identify a situation or practice that may seriously damage the
instrument, but will not cause injury.
Indicates information of general interest.
IMPORTANT
Highlights information necessary to prevent damage to software, loss of data, or invalid test
results; or might contain information that is critical for optimal performance of the system.
Tip
Highlights helpful information that can make a task easier.
SAFETY
!
WARNING
!
CAUTION
!
NOTE
!

Contents
Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 5 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
Contents
1. Introduction.........................................................................................................................8
1.1 Electrolytically Regenerated Suppressor ....................................................................................9
1.2 Overview of Suppression and Neutralization Modes ................................................................15
1.2.1 Mode of Operation Selection.........................................................................................................16
1.2.2 The AutoSuppression Recycle Mode .............................................................................................16
1.2.3 The AutoSuppression External Water Mode ..................................................................................17
1.2.4 The Chemical Suppression Mode ..................................................................................................17
1.2.5 The MPIC Suppression Mode........................................................................................................17
1.2.6 The Neutralization Mode...............................................................................................................18
1.3 Shipment and Storage..............................................................................................................19
1.3.1 Shipment ......................................................................................................................................19
1.3.2 Storage .........................................................................................................................................19
2. Installation.........................................................................................................................20
2.1 System Requirements ..............................................................................................................20
2.2 Electrolytically Regenerated Suppressor Control......................................................................22
2.2.1 Dionex Reagent-Free Controller (Dionex RFC) .............................................................................23
2.3 Dionex SCC-10 Suppressor current controller (Item # 074053)................................................23
2.4 Back Pressure Coils for the Dionex ERS 500, Dionex ERS 500e and
Dionex AERS 500 Carbonate...................................................................................................24
2.4.1 Assembly......................................................................................................................................24
2.5 Gas Separator Waste Tube for the Dionex ERS 500 .................................................................25
2.5.1 Assembly......................................................................................................................................25
2.6 Electrolytically Regenerated Suppressor Current Selection.......................................................25
2.6.1 Calculating the Optimum Current Setting ......................................................................................25
3. Operation...........................................................................................................................28
3.1 Chemical Purity Requirements.................................................................................................28
3.1.1 Inorganic Chemicals......................................................................................................................28
3.1.2 Solvents........................................................................................................................................28
3.1.3 Deionized Water ...........................................................................................................................28
3.2 Start-up....................................................................................................................................28
3.2.1 Hydration......................................................................................................................................29
3.2.2 Back Pressure Coil Pressure Test...................................................................................................30
3.2.3 Quick Back Pressure Check...........................................................................................................30
3.3 Plumbing for the AutoSuppression Recycle Mode Operation ...................................................31
3.3.1 Eluent Flow Path Connections in the AutoSuppression Recycle Mode ...........................................32
3.3.2 Regenerant Flow Path Connections in the AutoSuppression Recycle Mode....................................32
3.3.3 Installation in Thermal Chamber ...................................................................................................32
3.4 Plumbing for the AutoSuppression External Water Mode Operation ........................................34
3.4.1 Eluent Flow Path Connections for the AutoSuppression External Water Mode...............................35
3.4.2 Regenerant Flow Path Connections in the AutoSuppression External Water Mode.........................35

Contents
Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 6 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
3.4.3 Regenerant Flow Path Connections in the AutoSuppression External Water Mode
with Peristaltic Pump ....................................................................................................................36
3.4.4 Installation in Thermal Chamber ...................................................................................................37
3.4.5 Dionex SRD-10 Suppressor Regenerant Detector...........................................................................37
3.5 Plumbing for Chemical Suppression Mode Operation ..............................................................37
3.6 Plumbing for MPIC Suppression Mode of Operation ...............................................................37
3.6.1 Eluent Flow Path Connections in MPIC Suppression Mode ...........................................................38
3.6.2 Regenerant Flow Path Connections in MPIC Suppression Mode
Using Pressurized Water Delivery System .....................................................................................38
3.6.3 MPIC Suppression Mode Operation ..............................................................................................38
3.7 Plumbing for Neutralization Mode Operation...........................................................................40
3.7.1 Sample Liquid Line Connections for Dionex ERS 500e in Neutralization Mode.............................41
3.7.2 Regenerant Liquid Line Connections for Dionex ERS 500e in Neutralization Mode.......................41
3.7.3 Pump Trap Column Installation and Regeneration .........................................................................41
3.7.4 Neutralization Mode Operation .....................................................................................................42
3.8 Dionex ERS 500, Dionex ERS 500e or Dionex AERS 500 Carbonate Storage..........................43
3.8.1 Short Term Storage (3 to 7 days)...................................................................................................43
3.8.2 Long Term Storage (More than 7 days) .........................................................................................43
4. Example Neutralizer Mode Applications..........................................................................44
4.1 System Blank...........................................................................................................................44
4.1.1 Anion System Blank .....................................................................................................................44
4.1.2 Cation System Blank.....................................................................................................................44
4.2 Dionex CERS 500e Conditioning.............................................................................................45
4.3 System Calibration ..................................................................................................................45
4.3.1 Analysis of Acid Samples Containing High Concentrations of Transition Metals............................45
4.4 Recovery Data for Trace Anions in 25% Sodium Hydroxide....................................................46
4.5 Recovery Data for Trace Cations in 24% Sulfuric Acid............................................................46
4.6 Anion Example Applications ...................................................................................................47
4.6.1 Dionex IonPac®AS11 Gradient.....................................................................................................47
4.6.2 Dionex IonPac AS11 Gradient Analysis of 10% Sodium Hydroxide...............................................48
4.6.3 Dionex IonPac AS12A Isocratic Analysis of 25% Sodium Hydroxide............................................50
4.6.4 Dionex IonPac AS12A Isocratic Analysis of 20% Ammonium Hydroxide......................................52
4.6.5 Dionex IonPac AS12A Isocratic Analysis of 25% Tetramethylammonium Hydroxide....................53
4.6.6 IonPac AS12A Isocratic Analysis of 25% Tetrabutylammonium Hydroxide...................................54
4.7 Cation Example Applications...................................................................................................55
4.7.1 Dionex IonPac CS12A Blank and Standard Analysis .....................................................................55
4.7.2 Dionex IonPac CS12A Analysis of 24% Sulfuric Acid...................................................................56
4.7.3 Dionex IonPac CS12A Analysis of 25% Acetic Acid.....................................................................57
4.7.4 Dionex IonPac CS12A Analysis of 10% Hydrofluoric Acid...........................................................58
4.7.5 Dionex IonPac CS12A Analysis of 22% Phosphoric Acid..............................................................59
5. Troubleshooting Guide......................................................................................................60
5.1 Electrolytically Regenerated Suppressor Operational Status Displays Alarm State....................60
5.2 Small or Increasing Analyte Peak Areas...................................................................................61

Contents
Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 7 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
5.2.1 Suppressor Chemical Regeneration Steps ......................................................................................61
5.2.2 Suppressor Electrolytic Regeneration Steps...................................................................................62
5.2.3 Full or Extended Regeneration: .....................................................................................................62
5.3 High Background Conductivity................................................................................................64
5.4 Drifting Baseline .....................................................................................................................64
5.5 Noisy Baseline.........................................................................................................................64
5.6 Decreased Sensitivity...............................................................................................................66
5.7 System Back Pressure Increases Over Time .............................................................................66
5.8 Liquid Leaks............................................................................................................................67
5.9 Poor or unstable recovery of certain peaks. ..............................................................................67
5.10 Peaks and spikes in the absence of an injection ........................................................................67
5.11 Low Sample Response (Neutralization Mode Only).................................................................68
5.12 Low Neutralization Capacity (Neutralization Mode Only)........................................................69
6. Dionex ERS 500, Dionex ERS 500e and
Dionex AERS 500 Carbonate Suppressor Cleanup..........................................................70
6.1 Metal Contaminants or Precipitates..........................................................................................70
6.2 Organic Contaminants .............................................................................................................71
Appendix A –Current Settings................................................................................................72
A.1. Optimum Current Settings for Common Eluents; Dionex AERS 500 (4 and 2 mm)
and Dionex AERS 500e (4 and 2 mm) .....................................................................................72
A.2. Optimum Current Settings for Common Eluents;
Dionex AERS 500 Carbonate (4 and 2 mm).............................................................................75
A.3. Optimum Current Settings for Common Eluents; Dionex CERS 500 (4 mm and 2 mm)
and Dionex CERS 500e (4 mm and 2 mm)...............................................................................76
A.2 Current Settings for Older Detectors ........................................................................................79
Appendix B –Suppressor Controller.......................................................................................80
B.1 Dionex ERS 500 and Dionex ERS 500e Control for the CD20/CD25/CD25A
and ED40/ED50/ED50A (Dionex DX-500 instruments)...........................................................80
B.1.1 Dionex ERS 500 Control for the Dionex DX-120 ..........................................................................81
B.1.2 ERS Control for the CDM-3/PED-2 (Dionex DX-300 Instruments)................................................81
B.1.3 ERS Control for the Dionex DX-100 (Model DX 1-03) .................................................................81
B.1.4 SRC Controller .............................................................................................................................81
Appendix C –Alarm States for Older Instruments ................................................................84
C.1 Alarm States for the CD20/ED40 (Dionex DX-500 Instruments)..............................................84

1–Introduction
Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 8 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
1. Introduction
Suppressor: The role of a suppressor in Ion Chromatography is to remove the eluent and sample
counterions and replace this with regenerant ions thereby converting the eluent to a weakly
dissociated form prior to detection. Detection of analyte ions particularly with conductivity
detection is therefore feasible against a low background. The suppressor not only reduces the
background signal but also the noise associated with the signal. Furthermore, the analytes are
converted to the more conductive acid or base form, which enhances the signal, particularly for
fully dissociated species. Thus overall improvement in detection limits, as observed from the
signal to noise ratio, is achieved. When compared to, applications that do not use a suppressor,
i.e., single column ion chromatography, the improvement in noise with suppressed ion
chromatography far exceeds the noise performance of single column chromatography
applications. Hence the suppressor has become an integral part of the ion chromatography
instrument.
The suppressors from Thermo Fisher Scientific are designed for continuous operation and do
not require any switching or offline regeneration. Furthermore, the standards and the samples
are always exposed to the same suppressor device when pursuing ion analysis, thus ensuring
that the analytical parameters are consistent between calibration and analysis. From a simplistic
perspective there are two types of suppressors offered for continuous operation; electrolytically
regenerated suppressors and chemically regenerated suppressors. The electrolytic suppressors
operate continuously with a water source as a regenerant. In the recycle mode of operation the
water source is derived from the suppressed eluent, thereby making the suppressor operation
facile. The chemical suppressors operate continuously with an external regenerant source.
The electrolytic suppressor device also permits recycle of the eluent when installed in a system
with Eluent Recycle (ER) system.
Additionally, an electrolytic suppressor can also act as an electrolytically regenerated neutralizer
for the neutralization of basic or acidic matrices prior to injection. By neutralizing the matrix
ions, trace anionic or cationic species can be detected in strong acid or base samples.

1–Introduction
Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 9 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
1.1 Electrolytically Regenerated Suppressor
The Thermo Scientific™ Dionex™ Electrolytically Regenerated Suppressor (Dionex ERS™
500 Suppressor) replaces the Thermo Scientific Dionex Self-Regenerating Suppressor (Dionex
SRS™300 Suppressor) product line. The Dionex ERS 500 is an electrolytic suppressor with a
new hardware design that allows the suppressor to be more pressure tolerant than previous
generation suppressor devices. The suppressor flow pathway has been redesigned to optimize
band dispersion and improve the flow and sealing properties. The Dionex ERS 500 continues to
use the same cleaned ion exchange components (screens and membranes) as the Dionex SRS
300 suppressor devices; however the Dionex ERS 500 eluent channel uses an ion exchange
resin bed as opposed to a gasketed screen.
The Dionex Electrolytically Regenerated Suppressor (Dionex ERS 500) is available in two
versions: the Anion Electrolytically Regenerated Suppressor (Dionex AERS™500) and the
Cation Electrolytically Regenerated Suppressor (Dionex CERS™500) to support anion and
cation analysis applications. The Dionex ERS 500 system consists of an Electrolytically
Regenerated Suppressor, the Suppressor Control, back pressure coils, and the Gas Separator
Waste Tube, see Figure 1. This high performance, low maintenance AutoSuppression system
provides a reliable solution for Ion Chromatography.
Additionally, the Dionex ERS 500 offers high capacity suppression while adding minimal delay
volume to the analytical system. The Dionex AERS 500 provides continuous suppression of
traditional eluents, and more concentrated eluents up to 200 mM NaOH. The Dionex CERS 500
offers continuous suppression of concentrated eluents up to 100 mN H2SO4 or MSA. This high
capacity significantly expands the capabilities and simplifies the operation of Ion
Chromatography.
The Dionex ERS 500, Dionex ERS 500e and Dionex AERS 500 Carbonate suppressors are
available in 2 mm and 4 mm formats for use with 2, 3, 4, or 5 mm Ion Chromatography columns
and systems. The 2 mm Dionex ERS 500, Dionex ERS 500e and Dionex AERS 500 Carbonate
are specially designed with reduced internal volume to ensure optimum performance with 2 mm
columns and systems.

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 H2O 2H+ + 1/2O2+ 2e-
At the cathode H2O + 2e-2OH-+ H2
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

1–Introduction
Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 11 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
AERS 500, cation exchange functionality extends across the electrodes. The function of this is
to lower the resistance and aid in the transport of ions in and out of the eluent channel. In the
Dionex ERS 500 the eluent channel is filled with ion exchange resin and provides a static
capacity which is particularly useful when eluent is pumped into the device with the power off.
In operation the electrolytically generated hydronium ions in the Dionex AERS 500 are driven
towards the cathode along with eluent cations by the applied voltage. The membrane allows
hydronium ions to pass into the eluent chamber resulting in the conversion of the electrolyte of
the eluent to a weakly ionized form. For each hydronium ion entering the eluent channel one
hydronium or a cation exits the device and is driven towards the cathode. At the cathode the
cations combine with the electrolytically generated hydroxide ions to form water or base.
Overall the current dictates the concentration of hydronium and hydroxide ions.
The eluent suppression process is illustrated for Anion Suppressor in Figure 2 and for Cation
Suppressor in

1–Introduction
Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 12 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
Figure 3.
As shown in Figure 2, the water regenerant undergoes electrolysis to form hydroxide ions on the
cathode surface along with hydrogen gas while hydronium ions are formed in the anode surface
along with oxygen gas. In the Anion Suppressor, cation exchange materials such as screens,
membranes and resins allow hydronium ions to move from the anode chamber into the eluent
chamber to neutralize the hydroxide eluent. Sodium ions or eluent or sample counter-ions in the
eluent are driven by the applied electric potential towards the cathode and combine with the
hydroxide ions generated at the cathode to form sodium hydroxide waste. Hydronium ions can
also travel all the way to the cathode to form water, thus effecting suppression of the eluent and
conversion of the analyte to typically a more conductive acid form.
Figure 2 AutoSuppression with the Dionex AERS 500
The Dionex Electrolytically Regenerated Suppressor for External Water Mode (Dionex ERS
500e) is optimized for use in the external water mode. The Dionex ERS 500e hardware design is
similar to the Dionex ERS 500 hardware design from a sealing perspective and is optimized for
minimal band dispersion and improved flow performance. The Dionex ERS 500e uses the same
ion exchange membranes, screens, and resin materials as the standard Dionex ERS 500
suppressor. The Dionex ERS 500e is configured with a parallel regenerant flow to facilitate easy
supply and removal of regenerant and waste from the regenerant compartments making it
suitable for external water applications, as well as applications where organic modifiers (up to
40%) are present in the eluent or sample. The Dionex ERS 500e is required for applications
where borate is used as an eluent.
The Dionex ERS 500e (2 mm) suppressor is compatible with MS detection; the suppressor has
been designed to have minimal interference for MS applications and is designed for operation in
Dionex AERS 500 in AutoSuppression Mode

1–Introduction
Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 13 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
external water mode. The 2 mm suppressor is recommended for applications that use MS
detection due to the improved efficiency, and since less eluent enters the MS at the lower
operational flow rate.
The Dionex Anion Electrolytically Regenerated Suppressor for Carbonate Eluents (Dionex
AERS 500 Carbonate) is optimized for use with carbonate or carbonate/bicarbonate based
eluents and is available only as an anion version. The Dionex AERS 500 Carbonate hardware
design is similar to the Dionex AERS 500 hardware design from a sealing perspective and is
optimized for minimal band dispersion and improved flow performance. The Dionex AERS 500
Carbonate uses the same ion exchange membranes, screens, and resin materials as the standard
Dionex AERS 500 suppressor. The Dionex AERS 500 Carbonate is configured with a parallel
regenerant flow to facilitate easy supply and removal of regenerant and waste from the
regenerant compartments. The Dionex AERS 500 Carbonate operates similar to the Dionex
AERS 500 suppressor using electrolysis derived regenerant ions; however, it uses a three-
electrode design for the electrolysis function. The anode electrode is segmented into two
portions with an electrical gap. The anode electrodes are connected via a resistor thus resulting
in a lower applied current across the outlet section of the suppressor relative to the inlet section
of the suppressor. This design results in decreased gas production at the outlet, and as a
consequence, results in less variation in the suppressed background and is able to achieve low
noise.
As shown in

1–Introduction
Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 14 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
Figure 3, the water regenerant undergoes electrolysis to form hydroxide ions in the cathode
surface along with hydrogen gas while hydronium ions are formed in the anode surface along
with oxygen gas. In the cation suppressor, anion exchange materials such as screens,
membranes and resins allow hydroxide ions to move from the cathode chamber into the eluent
chamber to neutralize the acid eluent. MSA ions or eluent or sample counter-ions in the eluent
are driven by the applied electric potential towards the anode and combine with the hydronium
ions generated at the anode to form methane sulfonic acid waste. Hydroxide ions can also travel
all the way from the cathode and combine with hydronium ions at the anode to form water, thus
effecting suppression of the eluent and conversion of the analyte to a typically more conductive
base form.

1–Introduction
Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 15 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
Figure 3 AutoSuppression with the Dionex CERS 500
1.2 Overview of Suppression and Neutralization Modes
Four basic modes of suppression can be performed with the Dionex Electrolytically
Regenerated Suppressor (Dionex ERS 500, Dionex ERS 500e and Dionex AERS 500
Carbonate):
AutoSuppression Recycle Mode
AutoSuppression External Water Mode
MPIC Suppression Mode
Neutralization Mode
The Dionex ERS 500 is not compatible with the Chemical Suppression Mode. The Dionex
CRS 500 or equivalent should be used when Chemical Suppression Mode is required.
NOTE
!
CSRS 300 in AutoSuppression Mode
ANODE
+CATHODE -
ANALYTE IN H+ MSA-
ELUENT
(MSA)
Waste/Vent
MSA + O2H2O + H2
Waste/Vent
H2O
H2O
ANALYTE IN H2O
TO DETECTOR
3H2O 2 H2O
2H3O++ ½ O2 (g) H2+ 2 OH-
[H+ + OH-]
H2O
H+ + MSA-
MSA- + H+OH-
Dionex CERS 500 in AutoSuppression Mode

1–Introduction
Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 16 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
1.2.1 Mode of Operation Selection
The Dionex ERS 500 mode of operation depends mainly on the eluent composition, the analysis
sensitivity requirements and the sample matrix. The compatibilities are shown in
Table 1. For example, eluents containing organic solvents that tend to oxidize easily are not
compatible with the AutoSuppression Recycle Mode. The AutoSuppression External Water
Mode should be used instead, or a Dionex CRS suppressor employed in Chemical Suppression
Mode. The MPIC Suppression Mode is specifically designed for applications where ion-pair
reagents and solvents are present in the eluent. The Neutralization Mode can be used with any
eluent composition.
Table 1 Eluent Composition and Suppression Mode Compatibility
Eluent
Composition
Suppression
Recycle
Suppression
External Water(1)
Chemical
Suppression(2)
MPIC
Suppression
Aqueous Eluents (excluding
borate)
Yes
Yes
Yes
N/A
Borate Eluents
No
Yes(3)
Yes
N/A
Eluents containing
Organic Solvents that are
easily oxidized
No
Yes (Up to 40%)(3)
Yes (Up to 100%)
N/A
Eluents containing Organic
Solvents that are not easily
oxidized
Yes
Yes
Yes
Yes
Eluents Containing Ion Pair
Reagents with or without
Solvents
No
No
No
Yes
Simple Aqueous Samples
Yes
Yes
Yes
Yes (assuming Ion
Pairing Reagent)
Complex Samples or
Samples containing Solvents
No
Yes(3)
Yes
Yes (assuming Ion
Pairing Reagent)
(1)The Dionex ERS 500 is not recommended for External Water Mode; the Dionex ERS 500e is recommended for External Water Mode
applications.
(2)The Dionex ERS 500 does not support Chemical Suppression Mode. Use of a Chemically Regenerated Suppressor such as the CRS 500
or equivalent is recommended.
(3)Only the Dionex ERS 500e is compatible with Borate Eluents and Eluents or Samples containing Organic Solvents that are easily
oxidized.
1.2.2 The AutoSuppression Recycle Mode
The AutoSuppression Recycle Mode uses the suppressed conductivity cell effluent as the source
of water for the regenerant. This is the preferred method of operation for the Dionex ERS 500
and Dionex AERS 500 Carbonate. The Dionex ERS 500e is also compatible with this mode.
The advantage of this mode of operation is simplicity and ease of use. This mode reliably
provides AutoSuppression for most suppressed conductivity applications using solvent-free
eluents. For solvents that are not easily oxidized, such as iso-propyl alcohol, the
AutoSuppression recycle mode is preferred. As the eluent passes through the suppressor’s
eluent channel it is converted to a weakly ionized form. After detection, the cell effluent can be
routed back to the regenerant channel to provide the water required for the electrolysis reactions.
The amount of water flowing through the regenerant chambers is therefore limited to the eluent
flow rate. See Section 3 for complete operating instructions.

1–Introduction
Thermo Scientific
Product Manual for the ERS 500 Suppressor
Page 17 of 84
031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
The AutoSuppression Recycle Mode is not compatible with eluents containing Borate or
Organic Solvents that tend to oxidize easily, such as methanol.
1.2.3 The AutoSuppression External Water Mode
The AutoSuppression External Water Mode is used for any application requiring organic
solvents in the eluent or sample, or for applications using borate as the eluent ion. This is the
preferred method of operation for the Dionex ERS 500e. The Dionex ERS 500 and Dionex
AERS 500 Carbonate are compatible with this mode, but not with applications requiring
organic solvents in the eluent, or for applications using borate as the eluent ion. This mode
uses a constant source of deionized water from a pressurized bottle or other source of deionized
water that delivers 0.25 to 2 mL/min for 2 mm applications and 1.0 to 5 mL/min for 4 mm
applications, although the eluent flow rate is typically recommended as double the regenerant
flow rate. The amount of water flowing through the regenerant chambers is independent of the
eluent flow rate. The AutoSuppression External Water Mode eliminates the potential for build-
up of contaminating ions resulting from the oxidation of solvents. It is also recommended when
pursuing analysis with high concentrations of matrix ions. Any analysis performed using the
AutoSuppression Recycle Mode can also be performed using the AutoSuppression External
Water Mode. See Section 3 for complete operating instructions.
1.2.4 The Chemical Suppression Mode
The Dionex ERS 500 cannot be used in the Chemical Suppression Mode. The peak response
will not be maintained to a constant level in this mode. Thermo Scientific Dionex recommends
the use of a Chemically Regenerated Suppressor (Dionex CRS 500 or equivalent) for chemical
suppression applications. Please refer to the Dionex CRS Manual, Document No. 031727, and
the DCR Kit Manual, Document No. 031664.
The Dionex AERS 500 Carbonate and Dionex ERS 500e can be used in the Chemical
Suppression Mode; however the total suppression capacity is reduced compared to a
Chemically Regenerated Suppressor. Thermo Scientific recommends the use of a Chemically
Regenerated Suppressor such as the Dionex CRS 500 for chemical suppression applications.
1.2.5 The MPIC Suppression Mode
1.2.5.1 Anion MPIC
The Dionex AERS 500e is used for eluent suppression of Mobile Phase Ion Chromatography
(MPIC or ion-pairing) eluents by using the MPIC Suppression Mode. The Dionex AERS 500
and Dionex AERS 500 Carbonate are not recommended for this mode. The MPIC
Suppression Mode is a combination of the AutoSuppression External Water Mode augmented
with a chemical regenerant such as sulfuric acid (H2SO4). The MPIC Suppression Mode uses an
applied current and a constant source of dilute sulfuric acid solution from a pressurized bottle
delivery system. This mode must be used for MPIC applications requiring an ion pair reagent
and organic solvents in the eluent. The MPIC Suppression Mode reliably provides suppression
of typical eluents for MPIC applications using suppressed conductivity detection. The ion pair
reagents, such as tetrabutylammonium hydroxide (TBAOH), are used in concentrations
typically ranging from 1.0 to 5.0 mM. See Section 3 for complete operating instructions.
1.2.5.2 Cation MPIC
The Dionex CERS 500e is used for eluent suppression of MPIC eluents by using the
AutoSuppression External Water Mode or the MPIC Suppression Mode depending on the
specific MPIC application. The Dionex CERS 500 is not recommended for this mode. The
MPIC Suppression Mode uses an applied current and a constant source of dilute boric acid
NOTE
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1–Introduction
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031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
regenerant solution from a pressurized bottle delivery system. Dilute boric acid is added to the
water regenerant to enhance detection and improve linearity of weak bases such as ammonia
and amines. This mode is used for MPIC applications requiring an ion pair reagent and organic
solvents in the eluent. The MPIC Suppression Mode reliably provides suppression of typical
eluents for MPIC applications using suppressed conductivity detection. The ion pair reagents,
such as octanesulfonic acid (OSA), are used in concentrations typically ranging from 1.0 to 5.0
mM. Organic solvent concentrations should not exceed 40%. See Section 3 for complete
operating instructions.
1.2.6 The Neutralization Mode
The Dionex ERS 500 (4 mm) when operated in this mode requires a constant deionized water
flow of 3 to 5 mL/min through the regenerant chambers. The regenerant water can be delivered
from a pressurized bottle or pump. If using a pressurized bottle, it is recommend to use the
Dionex ERS 500e.
IMPORTANT
The Dionex AERS 500 Carbonate, Dionex ERS 500 (2 mm) and Dionex ERS 500e (2 mm)
suppressors are not designed or validated for the Neutralization Mode. The Dionex ERS
500e (4mm) suppressor is recommended and validated for this mode. The Dionex ERS 500
(4 mm) suppressor may also be used for this mode.
1.2.6.1 Neutralization Theory
Figure 4 AutoNeutralization of Concentrated Acid/Base with the Self-Regenerating
Neutralizer
Dionex AERS 500 Dionex CERS 500
As shown in Figure 4, when a potential is applied across the two electrodes, the water
regenerant undergoes electrolysis, forming hydronium ions at the anode and hydroxide ions at
the cathode.
In the Dionex AERS 500, hydronium is transported from the anode towards the cathode and
enters the sample chamber. At the same time, the matrix cations in the sample move towards the
cathode and enter the cathode chamber. The matrix cations combine with the hydroxide ions at
the cathode forming a base, and are removed from the regenerant chamber. The net effect of this

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transport of ions is neutralization of the sample matrix ions to a weakly ionized form while the
sample anions are typically converted to a strongly ionized form. The sample anions are now in
a weakly dissociated matrix such as water and are ready for analysis.
In the Dionex CERS 500 hydroxide is transported from the cathode towards the anion and enters
the sample chamber. At the same time, the matrix anions in the sample move towards the anode
and enter the anode chamber. The matrix anions combine with the hydronium ions at the anode
forming an acid and are removed from the regenerant chamber. The net effect of this transport
of ions is neutralization of the sample matrix ions to a weakly ionized form, while the sample
cations are typically converted to a strongly ionized form. The sample cations are now in a
weakly dissociated matrix such as water and are ready for analysis
1.2.6.2 Trace Ion Analysis After Neutralization
After neutralization, the sample can be fed into any Dionex Ion Chromatography system and
operated in the concentrator mode. It is important that only low pressure concentrator columns,
such as the Dionex UTAC-XLP2 (Item # 072781) and Dionex TCC-XLP1 (Item # 063889), be
used to protect the Dionex ERS 500 from damage.
1.3 Shipment and Storage
1.3.1 Shipment
The Electrolytically Regenerated Suppressors (Dionex ERS 500, Dionex ERS 500e, and
Dionex AERS 500 Carbonate) should not be subjected to temperatures above 50°C for long
durations during shipment, storage or operation, or for any duration above 80°C.
1.3.2 Storage
Ensure the suppressor is stored in a temperature controlled environment away from direct
exposure to sunlight or other sources of heat. Do not store the suppressor in an
environment where temperatures in excess of 50°C may be experienced, such as a parked
car.
CAUTION
!
CAUTION
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2–Installation
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Product Manual for the ERS 500 Suppressor
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031956-11 For Research Use Only. Not for Use in Diagnostic Procedures.
2. Installation
2.1 System Requirements
The Dionex ERS 500 and Dionex ERS 500e are designed to be direct replacements for the
Dionex SRS series of suppressors, such as the Dionex SRS I, Dionex SRS II, Dionex SRS
ULTRA, Dionex SRS ULTRA II and Dionex SRS 300. The Dionex ERS 500 can be used in
place of any of these suppressors where recycled eluent mode is employed.
The Dionex ERS 500e is designed to be a direct replacement for the Dionex SRS series of
suppressors where external water mode is employed. The Dionex ERS 500e features a hardware
design that significantly improves regenerant flow when operated in external water mode.
The Dionex AERS 500 Carbonate suppressor is designed for operation with carbonate and
carbonate/bicarbonate eluents. The Dionex AERS 500 Carbonate features a hardware design
that significantly improves noise performance with carbonate eluents without sacrificing
performance or ease-of-use. The unique hardware design delivers the lowest noise level of any
electrolytic suppressor for carbonate eluents.
The Dionex ERS 500 and Dionex ERS 500e are not designed to be direct replacements for the
Dionex SRS series of suppressors where these suppressors are being used in Chemical
Suppression Mode. If Chemical Suppression Mode is being used, the Chemically Regenerated
Suppressor (Dionex CRS 500) or equivalent is recommended. The Dionex AERS 500 Carbonate
and Dionex ERS 500e can be used in the Chemical Suppression Mode; however the total
suppression capacity is reduced compared to a Chemically Regenerated Suppressor.
The Dionex ERS 500e is also designed to be a direct replacement for the Dionex SRN series of
neutralizers, such as the Dionex SRN 300, Dionex SRN-II and Dionex SRN products.
The Dionex ERS 500, Dionex ERS 500e and Dionex AERS 500 Carbonate are designed to be
run on any Dionex Ion Chromatography System (ICS) equipped with an analytical Anion or
Cation exchange column set and an electrolytic suppressor controller, such as the Thermo
Scientific Dionex ICS-5000+, Dionex Integrion, or Dionex Aquion. They are not designed to be
run on a Dionex Capillary Ion Chromatography Systems, such as the ICS-4000, or on Dionex
Ion Chromatography Systems that do not have an electrolytic suppressor controller, such as the
Dionex ICS-90A, Dionex ICS-600 or Dionex ICS-900. Some legacy systems require a
standalone controller for installation of the Dionex ERS 500, Dionex ERS 500e or Dionex
AERS 500 Carbonate. See, “Electrolytically Regenerated Suppressor Requirements for
Selected IC Modules.”
The Dionex ERS control is provided by discrete (50, 100, 300, and 500mA) or non-discrete (0
to 500 mA in 1 mA increment) power supplies. Discrete Dionex ERS Control is integrated into
older systems, such as the CDM-3 and PED-2 of the Dionex DX-300, the Dionex DX-100
(Model 1-03), Dionex DX-120, Dionex DX-320 (IC20 and IC25 models), Dionex DX-500
(CD20 and ED40 detectors), and Dionex DX-600 (CD25 and ED50 detectors). The use of
discrete power supplies may not be suitable for optimal suppressor performance and may
affect the suppressor noise performance and life time.
It is therefore recommended to use a non-discrete power supply, such as the Thermo Scientific
Dionex RFC-10 or Dionex RFC-30. It is also possible to use the discrete power supplies with a
Dionex SCC-10 controller that provides twelve discrete current settings. Non-discrete Dionex
ERS Control is integrated into modern instruments, including the Dionex ICS series (excluding
Dionex ICS-90, Dionex ICS-90A, Dionex ICS-600 and Dionex ICS-900), Dionex Integrion and
Dionex Aquion.