Retardation Effect of Basic Nitrogen Compounds on Hydrocarbons Catalytic Cracking in Coker Gas Oil and Their Structural Identification

Ze-kun Li, Gang Wang,* Quan Shi, Chun-ming Xu, and Jin-sen Gao 

State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, China

*Corresponding Authors: Gang Wang − Email: wanggang75@163.com

Keywords: Catalysts; Chemical structure; Lipids; Nitrogen; Nitrogen compounds

Abstract:The basic nitrogen compounds in coker gas oil (CGO) narrow fractions were enriched, and their influences on hydrocarbons during fluid catalytic cracking (FCC) were investigated. The results show that the content of basic nitrogen compounds has influence on hydrocarbons cracking during CGO FCC reaction, but it is not as obvious as reported before. Furthermore, the compositional and structural identification of basic extracts by positive-ion electrospray Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) shows that basic nitrogen compounds in CGO include N, N₂, NO, N₂O₁, and NS class species. The N1 class species centered at 9 < DBE < 13 with a carbon number ranging from 20 to 24 is the most abundant, and it is a key for CGO’s retarding performance. The effect of structure and composition of basic nitrogen compounds is much more obvious than that of content, and it is stronger with the increase of their rings plus double bond equivalence (DBE).