Gas chromatographic method to determine formaldehyde traces in automobile exhaust gases

Summary A method for the gas chromatographic determination of traces of formaldehyde is described. The formaldehyde is detected by means of a modified FID which contains a microreactor inside the jet for the hydrogenation of formaldehyde to methane. Only a slight modification to an ordinary FID is needed with no additional gas tubes and no alteration to the existing detector heater. The additional dead volume and peak broadening is negligible. The system is calibrated by means of a gas generator. The described method is used for determining the content of formaldehyde in the exhaust gases of methanol-driven cars.Dedicated to Prof. Dr. István Halász on the occasion of his sixtieth birthday.