Identification of basic nitrogen compounds in ethanol-soluble portion from Zhaotong lignite ethanolysis by positive-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry

Analysis of extractable basic nitrogen compounds in Buliangou subbituminous coal by positive-ion ESI FT-ICR MS

“…2) of E 1 , E 2 , and E 3 contain ca. 2100, 1600, and 2100 peaks, respectively, including various BNCs [1,20,33]. From manual investigation of the observed peaks, it can be inferred that virtually all of the observed peaks are singly charged and therefore, the molecular masses (MMs) of detected compounds in E 1 -E 3 are within the range of 200-600 u.…”

“…The optimized mass for the quadrupole (Q1) is 150 u. An argon-filled hexapole collision pool was operated at 5 MHz and 700 Vp-p of radio frequency amplitude, in which ions accumulated for 0.2 s. The data size was set at 4 M. A total of 64 scans were collected to enhance the signal/noise ratio [33,34]. The FT-ICR MS was calibrated using a known nitrogen-containing species homologous series.…”

“…Bruker software Data Analysis was used for peak detection and molecular formula assignment. Detailed data processing was performed according to the recent investigations [29,[33][34][35][36]. The number of N atom in each molecular formula was limited up to 3 when mass peaks were assigned.…”

Insight into the structural features of Zhaotong lignite using multiple techniques

“…High quaternary nitrogen content could be related to pyridinic nitrogen protonation with phenolic hydroxyl groups. One important evidence is that numerous basic nitrogen compounds (pyridinic nitrogen) in the ESP were detected by positiveion ESI FT-ICR MS analysis [30]. It is unexpected that the relative content of chemisorbed nitrogen is more than 20%, which could be ascribed to the physical structures of ZL.…”

“…They only focused on N 1 species for neutral nitrogen compounds (NNCs). In our recent investigations [2,30], ZL was subjected to ethanolysis at 230-350°C and the resulting ethanol-soluble portion (ESP) obtained at 305°C with the highest yield of 64.9% was analyzed using ESI FT-ICR MS both in negative-and positive-ion modes for identifying oxygen-containing species and basic nitrogen compounds, respectively. However, NNCs in the ESP were paid less attention.…”