NETZSCH, in collaboration with JAS (Joint Analytical Systems), has forged a breakthrough improvement in evolved gas analysis (EGA). What sets the new coupling system apart is the fact that the start of the measurement is event-driven. This enables temperature-correlated detection of the substances released, which in turn allows for direct correlation with mass loss steps.
GC is a high-resolution method for separating volatile and semi-volatile compounds. The gas mixtures are separated based on the differences in component distribution between a stationary phase (e.g. inner coating of a capillary) and a mobile phase (purge gas, e.g. helium). Since this gas separation in the GC column takes a certain amount of time the duration of which depends upon sample characteristics, column flow rate, column length, and stationary and mobile phase it is not possible to couple directly into the GC with a continuous online sample gas flow. Our solution, therefore, was to develop a direct coupling in a quasi continuous mode by using heated automatic valves, which allows for software-controlled gas sampling (flow-through sampling loop) and gas injection even at short intervals.
Unique TG/STA-GC-MS coupling solution with event-controlled or temperature-dependent triggering
Perfectly heated gas transfer (300°C) from the TG/STA to the valve box and the injector at the GC
Fast and wide-range QMS for analysis of the gas chromatogram
Independent application of GC-MS for liquid/gas injection at any time
For GC-MS coupling, we rely on the world-renowned supplier, Agilent, along with our partner, Joint Analytical Systems (JAS). This allows for perfect GC-MS supply and service quality, as we at NETZSCH expect of any entity with which we do business, in order to guarantee optimized performance for our own products.
TG-GC-MS – Technical Specifications
Mass spectrometer (MSD Agilent)
Mass range: 1.6 u to 1050 u (*)
Mass filter: monolithic hyperbolic quadrupole
Mass resolution: Unique mass (adjustable by tuning)
Ionization: non-coated inert electron impact source
Ionization energy standard 70 eV (Selectable range: 5 eV to 241.5 eV)
2 filaments
Detector: triple axis SEM with long life EM
Scan rates: 12.500 u/s (electronically), 8.000 u/s write-to-disk
(*): unified atomic mass unit
Gas Chromatograph (Agilent)
Valve box can be heated to 300°C, with sampling loop of 250 µl
Unis 500 injector (split, splitless) max. 450°C
GC column: Standard HP-5ms capillary (30 m, max. 325°C, other columns available according to specific application)
Fast change of capillary columns without interruption of MS vacuum (swap'n go, JAS)
Column Furnace: 35°C to 425°C
Transfer system from TG or STA
Heated furnace adapter, max. 300°C (for MS, FTIR or GC-MS coupling)
Heated transfer line: Glass-lined steel tubing, max. 300°C (forced flow by pumping through the sampling loop)
Bypass system for excess gas at the furnace
