Development of a Formaldehyde Analyzer for Motor Vehicle Exhaust Emissions.

摘要

The purpose was to develop an electrochemical transducer which would selectively oxidize formaldehyde in the midst of all of the other gas species present in the exhaust stream of internal combustion engines. The current generated by this device would be amplified and displayed in a manner which would permit quantitative analysis of the formaldehyde concentration. The sensor which was developed was not as selective as proposed. However,its lack of selectivity applies only to members of the aldehyde family. It is equally sensitive to all aldehydes. The problem of evaluating the sensor's performance necessitated the completion of two other significant achievements: production of a reliable formaldehyde standard in the 1ppm concentration range;and development of a wet method of analysis which would give accurate yet fairly rapid measurements at this low level of pollutant.