NITROGEN DETERMINATION BY BOAT-INLET CHEMILUMINESCENCE: ASTM D5762
EXPLANATION
This test method covers the determination of nitrogen in liquid hydrocarbons including petroleum process streams and lubricating oils in the concentration range from 40 to 10000 μg/g nitrogen. For light hydrocarbons containing less than 100 μg/g nitrogen, Test Method ASTM D4629 can be more appropriate.
TEST SUMMARY
A hydrocarbon sample is placed on a sample boat at room temperature. The sample and boat are advanced into a high temperature combustion tube where the nitrogen is oxidized to nitric oxide (NO) in an oxygen atmosphere. The NO contacts ozone, is converted to excited nitrogen dioxide (NO2). The light emitted as the excited NO2 decays is detected by a photomultiplier tube and the resulting signal is a measure of the nitrogen contained in the sample.
TEST PRECISION
Repeatability: 0.099 X
Reproducibility: 0.291 X
Where X is the average of results obtained.
