Electrical Mobility Separation of Airborne Particles Using Integrated Microfabricated Corona Ionizer and Separator Electrodes

Airborne particles are separated according to their electrical mobilities using a microfabricated corona ionizer and separator electrodes. Oleic acid particles with sizes ranging from 30 to 300 nm are used to characterize the device. They are generated using a TSI 3075 constant output atomizer. These particles are electrically charged by a microfabricated corona ionizer, and the resultant particle electrical mobility is a function of the size of the particle. A varying DC potential difference of 0-2 kV across the separator electrodes selects charged particles of various electrical mobilities. These separated particles are subsequently counted using a TSI 3025A condensation particle counter. The device demonstrated its ability to separate particles between 50 and 130 nm into five distinct size bins. The operational flow rate is 0.5 L/min, and the micropin-between-planes corona ionizer operates at 1.3 kV with 7 muA. The theoretical and experimental electrical mobilities of the particles are compared.