EVALUATION OF CONTACT COLUMNS FOR NITROGEN DIOXIDE ABSORPTION

The absorption efficiencies of 6–, 10–, IS–, and 60-turn spiral contact columns for two formulations of Saltzman reagent are evaluated for use in atmospheric nitrogen dioxide analyzers at several air and liquid flow rates. Response times for the several columns as a function of flow rates and absorbing reagent are also given. The recommended column and reagent are indicated. The technique of adjusting instrument parameters for direct readout of NO2 concentrations is described.