简单介绍： 苯气体检测管121sp c6h6，measuring range 0.5 to 10 ppm number of pump strokes 3 correction factor 1 sampling time 1.5 minutes per pump stroke detecting limit 0.2 ppm (n=......
苯气体检测管121sp c6h6 产品详情
详情介绍：
苯气体检测管121sp c6h6
benzene21spc6h6performance
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
coefficient ofvariation 10% (for 0.5 to 3ppm), 5% (for 3 to 10 ppm)
shelflife 2 years
correctionsfor
temperature & humidity unnecessary
store the tubes at cool and darkplace.
possible coexisting substances and theirinterferences (note)
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.
calibration gasgeneration diffusion tubemethod
tlv-twa tlv-stel explosive range
0.5ppm 2.5ppm 1.3 to 7.1%