Thermo Scientific Dionex ICS-5000, Operator'S Manual

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2 • DC Description
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The eluent/sample mixture is pumped through a temperature stabilizer
(analytical IC only), through the guard and separator columns
, and
then through the suppressor .
•
From the suppressor, the mixture flows through a CRD (if installed) to
the cell , where the analytes are detected. A digital signal is sent to
Chromeleon software.
•
The mixture flows out of the cell and is recycled back into the
suppressor
, where it is used as the water source for the regenerant
chamber. Regenerant flow is routed through the CRD (if installed),
through the EG degas tubing , through the CR-TC , and then out to
waste .
2.15 ED Electrochemical Detector
One or two Dionex ICS-5000 Electrochemical Detectors (EDs) can be
installed in the DC. Each complete ED assembly consists of an amperometric
detection cell and the detector electronics required to collect data and send it
to the computer and the analog output (if installed). The detector is installed in
the upper compartment of the DC (see
Figure 2-21 ). The cell mounts on the
front of the detector. The detector electronics are not accessible to the user.
The ED can perform the following electrochemical detection modes:
•
DC amperometry (see Section 2.19.1 )
•
Integrated amperometry—includes pulsed amperometric detection (PAD)
and integrated pulsed amperometric detection (IPAD) (see
Section 2.19.2 )
•
Cyclic voltammetry (see Section 2.19.3 )
2.15.1 Electrochemical Detector Cell
The ED cell includes three different electrodes. It is a miniature flow-through
amperometric detection cell with a titanium cell body (the counter electrode),
a working electrode, and a combination pH-Ag/AgCl reference electrode (see
Figure 2-30 ) or a PdH reference electrode. The type of working electrode
used depends on the application. Four conventional (non-disposable) working
electrode types are available: gold, platinum, silver, and glassy carbon. Five
disposable working electrode types are available: gold on two different
substrates (polyester or PTFE), silver, platinum, and carbon.
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