A review of Chemiluminescent techniques for air pollution monitoring

Abstract

Abstract The practical application of chemiluminescent reactions to the detection of gas‐phase air pollutants is about four years old. During this relatively short period, such methods have evolved through the stages of conception, feasibility testing with laboratory breadboards, construction of prototypes, development of commercial models, field evaluations and the adaptation of the method, in two cases, as a recommended standard. A considerable number of reports on chemiluminescent techniques have appeared during the last 3–4 years. Some of these are unpublished reports of recent origin and others are government reports which have heretofore been relatively inaccessible. This review is intended to collect and publicize the recent research efforts in this rapidly growing field. Emphasis is placed on chemiluminescent detectors for O3 (O3 + ethyIene), NO (NO + O3), and sulfur compounds (flame chemiluminescent detection), which are being applied routinely in atmospheric monitoring. Recent studies are included on detection of NO2 by conversion to NO and subcequent chemiluminescent detection with O3. Other promising chemiluminescent methods discussed are detection of SO2, CO and NOX (NO+NO2) by O‐atom chemiluminescence, direct chemiluminescent detection of NO2 by a photofragment technique, and chemiluminescent detection of NH3 after conversion to NO. In addition to the flame photometric detection of sulfur compounds, brief descriptions are given of flame chemiluminescent techniques for nitrogen, phosphorous, boron and halogen containing compounds.