A gas chromatographic detector based on the quenching of luminescence from a P₄/O₂ cold flame

Abstract

Gas chromatographic effluents were detected by their quenching effect on the luminescence of a steady 'cold flame', as provided by the gas-phase reaction of phosphorus vapor and oxygen. The response of organic compounds correlated with their 'ease of oxidation' in accordance with the literature, suggesting that such compounds act as oxygen atom scavengers in the branched-chain P4/O2 reaction.Most substances showed linear response over one to two orders of magnitude, and minimum detectable amounts ranged from 2 × 10−9g (benzaldehyde) to 2 × 10−4g (dichloromethane). The detector temperature could be varied to (a) alter response ratios, i.e. selectivity, among some types of compounds; and (b) produce easily-obtained Arrhenius plots. However, the response (luminescence quenching) of most compounds was independent of temperature over a considerable range.