Photometric Flow Injection Determination of Formaldehyde in Atmospheric Air Using Chromatomembrane Absorption

Abstract

The photometric flow injection technique using the chromatomembrane preconcentration method was developed to determine the trace amounts of formaldehyde in a stream of air. It is based on chromatomembrane absorption of formaldehyde from the air to a microvolume of distilled water followed by the determination of the product formed upon the reaction of formaldehyde with acetylacetone in the carrier stream under the heating at 90°C. The detection limit of formaldehyde decreased proportionally to the time period of absorption and was 10 μg/m after 6 minutes at air flow rate 500 ml/min. Temperature dependence of the partition coefficient of formaldehyde in the system of air/water was established and the technique for generating the modeling gas mixtures with the given concentration of the formaldehyde was offered by the passing nitrogen gas through the water solution of formaldehyde.