[SRI GCs-m5] [SRI GCs] [PeakSimple DataSystem] [SRI GCs 2016] [SRI Custom GCs] [SRI MultiGas Analyzer GCs] [SRI MGA-5 Update] [SRI015 NEW Ideas] [SRI Tech Resources]

MGA#5 is a Unique SRI Configuration
PD2016-1.pdf2016-12016-1F   acrobat (2.3Mb)

  • TCD for 100ppM LOD to (mid) percent
  • FID-Methaniser down to low ppM CO/CO2
  • S-Cpds requires a FID-FPD (optional)
  • HS-D maybe a limitatiom(ethanol Max);may require other HaySep (Q, N, S etc ) columns for limited polar compounds . . . > also tr
  • Restek MicroPacked HayeSep columns or PLOT Columns as options
    Dual Oven extra possibity 8619D as a MG#5 option ?Trace Gas Analysis (low ppB) -  a “custom” more specialised App  > ASK!
    - requires HID ( VICI Valco & a different format GC eg SRI 8610V
    SRI HID ???  H2 > ASK SRI ? for specs re sensitivity -but  not necessarily recommended by SRI A!

“SHINCarbon ST - DOES offer a one-column analysis of O2/N2 CO/CO2
BUT NOT without it’s own idiosynchrasies / problems
eg AR/O2 No! / C2 max at >300C ?;
O2/N2 requires LDV HID and > 4m Packed Column
    
ASK for details / advice ! > but these are NOT necessarily just for SRI GCs /TCDs“ but ALL OEM brands of GCs > Buyer BWhere !

Multi-Gas Analysis - NO Simple Answers > many Options > this applies to ALL GCs any brand!
          SRI’s  MGA#5 is far BETTER Than Most designs !
- more innovative . . . for a very difficult still existing  gas analysis problem

  • H2 Quantitation requires use of Ar Carrier NOT He
  • TCD almost useless requires low Dead-volume VICI HID Detector  for CAPILLARY PEAKs
  • Ar / O2 separation is very difficult and requires PLOT MS5A Column - some other  limitations
  • MS5A becomes deactivated if repetiitive runs and with excessive water/CO2 in matrix Gas
     > dual Oven 8610D optional (??? ASK!) re GasValves as well ?!
  • S-cpds can deactivate the Methaniser Answer ? ASK!
  • excess water / humid samples ( we suggest>  a Nafion Drier on the sample stream prior to GC )
                          ASK for some (more) ANSWERS !
MGA#5 ConfigB
MGA#5 Options
MGA#5 Config

Other limitations / “issues”

In practice the HaySep-D is needed for CO2 separation but is somewhat limited for higher MS VOCs by column bleed and/or flow sensitivity drift of the TCD during temp programming to propane(?) EtOH, MEK for example at 180C max unless you use ultra pure He and/or Oxytraps

The HS-D can be replaced with capillary column for more detailed resolution of hugh MW or polar components but CO2 is then sacrificed !

Calibration of these is assisted by the on-column liquid injection porr fitted standard on the MG#5

The set up is somewhat convoluted and users need to understand the logic and peculiarities of the GC set-up re “Timed Events” of PeakSimple and multiple peaks etc !

Definitely NOT a “DO-All . . . Do everything” !  concept & NOT For GC BEGINNERS !

  • For H2 an extended design of the MG#5 becomes too complex mechanically / re GC internal space etc
    >
    a separate GC(s) using Argon carrier gas is recommended
    For high concentrations of H2 a simplified GC / is suggested using a CCD Detector ( 500ppM LOD) with 1 cc sample size for H2, CO, H20, methane and C2 > but probably NOT CO2 or Air ( Ar/ O2/ N2 )
     > much lower cost
  • columns to be decided on MolSieve for CO fromHAir) and CCD Not suitable for capillary columns CO2 probably non-reponsive in CCD and no need to separate CO2  on HS-D; backflushing of the CCD may still be required and can suffer from over saturation (high %) ???

Not yet implemented or actually offered by SRI

On-Lne auto analysis of gases AND complex VOCs is fraught with difficulties particularly related to
“Headspace Gases Analysis” ( re sample size available from the process  AND LODs and the need for more sophisticated GC Detectors

NO Equivocation here ! . . . Just stark reality

  • Yes there are some answers here! > but . . . more complex, more expensive > ASK !