A comparison of different methods in the analysis of the nitrogen content of nitrocellulose

Abstract. The energy content of nitrocellulose (NC) is governed by its level of nitration. This is normally described as the nitrogen content (% N) of the nitrocellulose. In this paper, three different methods were evaluated on seven different NC materials and compared to the specification provided by the producer. The first method was the well-established titration with ferrous ammonium sulphate, which provided a good reference, as this is the standard method in the industry. The second method was elemental analysis, where the instrument was calibrated against trimethylolpropanetrinitrate (TMPTN). This allowed direct analysis without addition of methanol, which is usually to prevent the too low values that can result from the mismatch in burn rate between NC and the inert references. The final method was 13C NMR, which has not been published since the advent of modern integration softwares to the best of our understanding. The methods are compared in terms of relative standard deviation, the effort and time required to prepare the samples and run the analysis, and operator dependency. review.