Measurement of Soot in Ambient Air – Determination of Elemental Carbon (EC) after Thermal Desorption of Organic Carbon (OC) Based on VDI 2465-2 Application Note · multi EA 5100

Introduction

Elemental carbon (EC) and organic carbon (OC) are two important parameters for environmental protection, health and safety at work. Their reliable and rapid determination is essential for sufficient air quality, as EC-/OC-containing particles of incomplete combustion products have carcinogenic, environmentally harmful effects. In the combustion process of fossil fuels (e.g., petroleum, coal, natural gas) and other organic substances in industry, transportation and in private households, the contained organic hydrocarbons are mainly oxidized to CO2 and water. If this process is not completed, e.g., due to a lack of oxygen or too low temperatures, soot is formed in addition to the CO2. The poorer the combustion quality, the higher the amount of generated soot. This substance consists of elemental carbon and many other higher condensed organic hydrocarbons, adsorbed on the surface of the soot particles. As elemental carbon is considered to be the most important cause of lung carcinomas, this parameter is limited and must therefore be strictly controlled.

Adherence to these limits is especially relevant in production facilities with diesel engine-driven vehicles operating in closed rooms, underground mines, in industrial urban areas or along congested inner city arterial roads.

The EC parameter is also of major interest in engine and catalytic converter research, for monitoring the effectiveness of combustion, exhaust filters and the activity of catalyst materials.

The combustion-based elemental analyzer multi EA 5100 offers an automated, quick and reliable alternative to timeconsuming competing techniques. The process utilized is mainly based on the recommendations of the VDI 2465 sheet 2, with improvements in matters of processing time and calibration.