Standard Test Method for Ultra Low Nitrogen in Aromatic Hydrocarbons by Oxidative Combustion and Reduced Pressure Chemiluminescence Detection
This test method is useful to detect and quantify Nitrogen-containing compounds at a concentration of 0.1 to 1.2 mg N/kg in light aromatic hydrocarbons used or produced in manufacturing process. These Nitrogen-containing compounds are undesirable in finished aromatic products and may be used in setting specification for determining the Total Nitrogen content in aromatic hydrocarbons.
ASTM D7184 requires the use of reduced pressure at the detector. Loss of vacuum or pressure fluctuations impact the sensitivity of the detector and the ability to determine Nitrogen concentrations less than 1 mg N/kg.
This test method covers the determination of Total Nitrogen in aromatic hydrocarbons, such as benzene, toluene, and xylene and it is applicable for samples containing Nitrogen from 0.1 to 1.2 mg N/kg. For higher Nitrogen concentrations refer to Test Method ASTM D4629. With careful analytical technique, this method can be used to successfully analyze concentrations below the current scope.
Working range Total Nitrogen : 0.1 – 1.2 mg/kg
Boiling range : 25 – 400 °C
Sample types: Aromatic hydrocarbons such as benzene, ethylbenzene but also pentane (C5) type of samples
To comply with ASTM D7184, NEXIS TN and combined instrument configurations like TN/TS with fully automatic liquids injection through AS120 Liquids Autosampler configurations for this ultra-trace level Total Nitrogen analysis.