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Debubblers & Degassers
Stand Alone MINI Degassers
Why Degas Your Mobile Phase?
Dissolved air in HPLC mobile phases can result in fow rate instability and
baseline disturbance.
Flow rate instability:
Non-degassed mobile phase can outgas in the
pumphead, causing bubbles to be formed and trapped inside the head
or check valves. These bubbles can cause fow disturbances and pressure
fuctuations, resulting in fow rate instability.
Baseline disturbance:
As the mobile phase passes through the column,
it experiences a large pressure drop. Non-degassed mobile phase can
outgas due to this pressure differential, causing air bubbles to form.
Air bubbles passing through or lodging in the fow cell cause detection
disturbances, exhibited as baseline noise.
Why Use a Degassing System?
Helium sparging is a common means of degassing HPLC solvents.
This method has its drawbacks, however. Sparging is a relatively ineffcient
method. Helium tanks are expensive and bulky, and solvent backup and
contamination are concerns. In addition, helium sparging can change the
composition of a premixed mobile phase over time, due to the difference
in the evaporation rates of mobile phase components.
In contrast, the Systec
®
Degassing System has none of these drawbacks,
and it is extremely fast and effcient at removing dissolved gases—
more effcient than helium sparging or PTFE-based degassing systems.
Tubing Connections
We recommend ETFE tubing (page 73) be used to limit regassing of mobile
phase between the degasser and your pump. ETFE is recommended because
of its superior impermeability to gases (compared to PTFE, FEP and PFA
tubing). Applicable fangeless fttings for 1/8” OD tubing are found on page 26.
GPC and HFIP Applications
Standard degassing chambers, with PEEK
™
bulkhead unions,
are not recommended for GPC applications or for use with HFIP
(hexafuoroisopropanol). Special GPC “hardened” versions are
available. Please contact us for more information.
Application Note
Stand-Alone Degassing Modules
Maximum number of degassing channels
5
Degassing Effciency
†
@ 1 mL / min MeOH >70% O
2
Removal
Membrane Material
SYSTEC AF
Other Wetted Materials
PEEK, PPS(GF), PTFE(GF), FEP
Solvent Compatibility
Not compatible with fuorinated solvents.
Special version available for GPC solvents.
Flow Path ID
1.14 mm (0.045”)
Internal Volume
480 µL (standard)
Maximum Pressure (@ 25 °C)
0.5 MPa (70 psi)
Pressure Drop
0.18 bar/mL/min
† Degassing effciency can be optimized based on fow rate, fuid to be degassed, and gas to be removed.
1. Standard ID; other sizes available
Specifcations
Vacuum Pump
Eluent
Controller
Degassing
Chamber
HPLC Pump
Injector/
Auto
Sampler
Dissolved gases are actively removed from a fowing liquid
stream by vacuum via the Systec AF
®
membrane.
To Vacuum
Controller
To Vacuum
Pump
Degassed
Eluent Out
Eluent In
Dissolved
Gas
Typical Degasser Implementation
FOR ORDERING & DISTRIBUTOR INFORMATION +1 800 426 0191 • +1 360 679 2528 • www.idex-hs.com