Formaldehydes Measurement Using Laser Spectroscopic Gas Analyzer

The use of alternative fuels, especially oxygenated fuels in automobile engines, has been increasing owing to the stringent global fuel economy and emission regulations. As a result, it is concerned that the emissions of alcohols and aldehydes have increased significantly. Aldehydes, formaldehyde (HCHO) in particular, are non-criteria pollutants that are acutely toxic and/or carcinogenic. Several reports have associated HCHO with potential lung and airway cancers. Therefore, emission regulations for these compounds have already been implemented in several areas worldwide. The conventional measurement (impinger, etc.) methods for HCHO possess advantages and disadvantages. HCHO can be measured with high sensitivity if measured in a batch. However, in real-time measurements, low concentration measurements are challenging. To overcome this challenge, a real-time HCHO analyzer for low concentration measurement of 0.1 ppm resolution in real time of 10Hz was developed in this study based on laser spectroscopic principles. The results in this study highlight the fundamental performance of the method and application to real automobile exhaust gas measurements.