苯气体检测管121SP C6H6    的详细介绍   
Measuring Range
0.5 to 10 ppm
Number of Pump Strokes
3
Correction Factor
1
SamplingTime
1.5 minutes per pumpstroke
DetectingLimit
0.2 ppm (n=3)
ColorChange
White → Brown
ReactionPrinciple
2C6H6+ HCHO → C6H5CH2C6H5  + H2O
C6H5CH2C6H5  + H2S2O7  → Condensation poiymer
Substance
Concentration
Interference
Change color by itself
Hexane
500 ppm
No effect
No discoloration
Toluene
100 ppm
No effect
No discoloration
Xylene
100 ppm
No effect
No discoloration
Aromatichydrocarbons other than benzene are trapped in the brown layer inthe pretreatment tube.If the pretreatment reagent is entirelyconsumed (whole brown layer turns to dark brown),ahigher reading will be given.