【国外标准】 Standard Test Method for Ultra Low Nitrogen in Aromatic Hydrocarbons by Oxidative Combustion and Reduced Pressure Chemiluminescence Detection

5.1 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.5.2 This test method 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.1.1 This test method covers the determination of total nitrogen in aromatic hydrocarbons, such as benzene, toluene, and xylene.1.2 This test method is applicable to samples with nitrogen concentrations up to 1.2 mg/kg. The Limit of Detection (LOD) is 0.04 mg/kg N and the Limit of Quantitation (LOQ) is 0.13 mg/kg N. For higher nitrogen concentrations refer to Test Method D4629. With careful analytical technique, this method can be used to successfully analyze concentrations below the current scope (see Appendix X1).NOTE 1: LOD and LOQ were calculated using data in ASTM Research Report RR:D16-1044.1.3 In determining the conformance of the test results using this method to applicable specifications; results shall be rounded off in accordance with the rounding-off method of Practice E29.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 9.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.