Pyrolysis temperature effect on compositions of basic nitrogen species in Huadian shale oil using positive-ion ESI FT-ICR MS and GC-NCD

Positive-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) and gas chromatography-nitrogen chemiluminescence detection (GC-NCD) was used to study the effect of pyrolysis temperature (400 degrees C, 430 degrees C, 460 degrees C, 490 degrees C, and 520 degrees C) on basic nitrogen compounds in Huadian shale oil. Because of the effect of secondary cracking, the relative contents of aliphatic amines and anilines decreased with increase in pyrolysis temperature. The relative abundances of N-1 classes decreased first but later increased. The relative abundances of N2OX and N3OX increased first but later decreased, and reached the maximum at 460 degrees C, which were 21.47 % and 5.27 %, respectively. As the pyrolysis temperature increased, the relative abundance of the N-1 classes within the carbon number ranged from 10 to 30 obviously increased. In conclusion, the pyrolysis temperature had an effect on the number, relative abundance, DBE distribution and carbon number distribution of heteroatom compounds in shale oil.

Automated summary

Positive-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) and gas chromatography-nitrogen chemiluminescence detection (GC-NCD) were used to study the effect of pyrolysis temperature on basic nitrogen compounds in Huadian shale oil. The results showed that the relative contents of different nitrogen compounds changed with increasing temperature, demonstrating the influence of pyrolysis temperature on the distribution of heteroatom compounds in shale oil.