Abstract: The hydrotreating of Jiujiang pipeline oil vacuum residue was carried out in a bench scale ebullated bed reactor. The structures of nitrogen compounds in feed and hydrotreated oils under different temperatures were investigated by using the Orbitrap mass spectrometry. The results showed that the nitrogen compounds in the vacuum residue include basic nitrogen compounds and neutral nitrogen compounds, with the types including N1, N1O1, N2, N2O1, mainly N1 compounds. In the conversion of feedstock, the carbon number distribution and equivalent double bond number (DBE) of the basic nitrogen compounds moved toward higher carbon munber and lower DBE; and the higher the reaction temperature, the more obvious the trend. With increase of reaction temperature, the DBE of neutral nitrogen compounds decreased,and for the intensifying of the thermal cracking reaction,the carbon munber was reduced.

Key words: ebullated bed, vacuum residue, Orbitrap MS, nitrogen compound