Perchloroethylene detection in air: a comparative study using polymer sensor elements and catalyst/sensor systems

摘要

In a first approach, perchloroethylene (C$-2$/Cl$-4$/ or 'PER') was determined quantitatively in air by monitoring mass and temperature changes of polymer- coated quartz microbalance and calorimetric transducers. The different equilibrium and time-dependent sensor responses result from reversible interactions between perchloroethylene molecules from the gas phase and chemically sensitive polymers based upon modified siloxanes. In a second approach, we determined PER by applying pattern recognition methods to evaluate data from catalyst/electrochemical sensor-systems. Here, PER is decomposed at a heated catalytic filament. The molecular fragments are detected subsequently by an electrochemical or semiconductor gas sensor. The quantitative determination of perchloroethylene in air in the ppm-range is possible by applying mathematical procedures of pattern recognition. Finally, a comparative discussion of the different transducer and evaluation principles is given for specific applications.