Analysis Solution - Determination of Non Methane Total Hydrocarbons in Environmental Air by Gas Chromatography

Introduction:

This method is applicable for the determination of total hydrocarbons, methane, and non methane total hydrocarbons in ambient air, as well as for the determination of total hydrocarbons, methane, and non methane total hydrocarbons in the air at unorganized emission monitoring points of pollution sources.

When the injection volume is 1.0 ml, the detection limits for total hydrocarbons and methane determined by this method are both better than 0.06 mg/m3 (calculated as methane), and the detection limit for non methane total hydrocarbons is better than 0.07 mg/m3 (calculated as carbon).

Method principle:

Inject the gas sample directly into a gas chromatograph equipped with a hydrogen flame ionization detector, and measure the content of total hydrocarbons and methane on the total hydrocarbon column and methane column, respectively. The difference between the two is the content of non methane total hydrocarbons. At the same time, using hydrocarbon removal air instead of the sample, measure the response value of oxygen on the total hydrocarbon column to deduct the interference of oxygen in the sample on the determination of total hydrocarbons.