TDS 3 Brochure.pdf

Technical Summary
GERSTEL Thermal Desorption Systems
Thermal Desorption System
TDS 3
Transfer capillary
Desorption tubes
Glass liner
Conventional thermal desorption systems
usually consist of a desorption unit, a cooled
trap and a GC inlet. The TDS 3 is a highperformance
thermal desorption system that
uses the GERSTEL cooled injection system to
function as both a cryogenic trap and a GC
inlet. Analytes are focussed in the inlet liner,
not the column, before being transferred onto
the analytical column as a narrow band. The
use of the inlet liner as a trap allows much
greater flexibility when trapping analytes and
protects the column from water and
contamination.
Desorption tubes can be initially cooled and
flushed with carrier gas to remove oxygen,
water or unwanted solvents. Two temperature
ramps are available to heat the tube up to
400°C. Analyte loss is avoided during transfer
from the TDS 3 to the CIS by using a transfer
line that is only 15 cm in length that can be
heated from ambient room temperature to
400°C.
The combination of the CIS and the TDS permit
a high desorption flow by trapping analytes in
the glass inlet liner of the CIS while excess gas
flows out the split vent. The system is capable
CIS 4
of a wide range of sampling modes
(from splitless to very high split ratios)
providing a dynamic range that allows
trace constituents to be determined as
easily as major sample components.
The manually operated TDS can be
upgraded to a fully automated system
capable of analyzing up to twenty
samples by adding the TDS A2.
Control and programming
The TDS 3 and TDS A2 are added to a
CIS system by simply adding the
appropriate circuit boards to the
C506 controller. System control and
programming can be carried out using
the controller's handheld keypad or by
using the GERSTEL MAESTRO software.