SELECTIVE ENHANCEMENT FOR NEON DETECTION IN A HELIUM DISCHARGE PHOTOIONIZATION DETECTOR

The helium discharge photoionization detector (HD-PID) is a very relia ble and highly sensitive gas chromatographic detector for the determin ation of trace amounts of inorganic gases. However, the sensitivity of the HD-PID is poor for neon, similarly to a helium ionization detecto r (HID). The improvement of the HD-PID sensitivity, especially for neo n, was studied. When helium containing 3.8 ppm (v/v) of neon was used as the helium discharge gas, the results obtained showed that the sens itivity for neon could be improved sixfold compared with that of the H D-PID under ordinary operating conditions.