Multiselective electrolytic conductivity detector  
       
   
     
   
     
   
     
     
     
     
     
     
     
       
    Contents  
     
       
    This gas chromatographic detector was patented by the Fraunhofer Institut, Germany, and is based on the dissociation of substances in electrolytic solutions and the resulting difference of the electrolytic conductivity. Noise, as well as the drift of the baseline and polarization effects are minimized by a pulse optimized cell with a volume of 6ul and a well adapted electronics. TOP
       
       
    Features  
   
  • detection of sulfur, nitrogen and halogenes
  • structur independent quantitative and qualitative trace anaylsis
  • wide linearity range up to 5 decades
  • detection limit down to the ppt range
  • no memory effect with high concentrations
  • powerful combination with purge-and-trap and headspace systems
  • simple adaption to each gas chromatograph
  • easy maintenance
  
       
    Selection of 3 modes  
   
  • "Reductive-Mode: not dissociating substances are reductively converted to dissociating substances in a catalytic reactor
  • "Oxidative-Mode": not dissociating substances are oxidatively converted to dissociating substances in a catalytic reactor
  • "Direct Mode": measurement of directly dissociating substances, e.g. amines, carbonic acids, chlorinated substances
  
       
   

Selectivity, detection limits and linearity

  
   
 
Reactor mode
Direct mode
Selectivity halogenes nitrogen sulfur amines
Mode reductive reductive oxidative direct
Reaction gas hydrogen hydrogen synth. air hydrogen
Additional gas vinyl chloride methylamine sulfur dioxide methylamine
Detection limit 20 pg Cl / s 20 pg N / s 50 pg S / s 20 pg DEA /s
Linearity 5 decades 5 decades 5 decades 3 decades
Cross sensitivity

Cl: C
= 10exp5

Cl: N = -1

Cl: S = 5

N: C
= 10exp5

N: Cl = -1

N: S = -5

S: C
= 3*10exp3

S: Cl = 1

S: N = 10

DEA: C
=10exp5

DEA =dietylamine
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    Actual chromatograms  
     
       
    Scope of supply  
    Electronic unit: amplifier, power supply, reactor heating  
    Main unit: 100ml ion exchanger, 100ml activated carbon  
    Reactor with cell: for reactive and oxidative mode  
                  
  We install this detector to every gas chromatograph !  
     
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