Automatic Dumas Nitrogen Analyses of Lubricating Oils and Additives.

Direct Dumas Determination of 30 to 1000 Parts per Million of Nitrogen in Oils.

“…Perfect combustion conditions are also required. Small amounts of gases such as methane or ethylene which are the products of incomplete combustion (2) may not be serious when the nitrogen content is in the 1-10% range but they cannot be tolerated in the 30-500 p.p.m. range.…”

“…Recently, Gustin's (3) automatic Dumas apparatus, which is available commercially as the Coleman Nitrogen Analyzer Model 29, has been used to determine 0.2% nitrogen in oils directly and down to 20 p.p.m. after a concentration step (2). Now Coleman has a new nitrogen analyzer, Model 29A, (1) which has larger combustion tubes, a higher temperature furnace, and a larger capacity nitrometer than the Model 29, so that it is better suited for combustion of large samples.…”

Determination of Trace Nitrogen in Petroleum by a Microcombustion Technique.

“…A number of other stationary phases petroleum fractions is amply demonstrated by the frequency with which such methods appear in the literature (1,3,5,9,10).…”