Vacuum residue (VR) is one of the more difficult heavy fractions to process in petroleum refining, and the development of clean utilization technologies for vacuum residue has become a major research focus in the petrochemical industry. This paper discusses the compositional and structural characteristics of vacuum residue from Karamay (KVR) using methods such as ultimate analysis, FTIR, and TG-DTG. The thermal gravimetric kinetics analysis was conducted based on TG-DTG curves at different heating rates. Ultimate analysis revealed that KVR has a high H/C atomic ratio (1.84), and combined with the strong peaks at 2920 cm−1 and 2850 cm−1 in its infrared spectrum, it indicates that KVR is mainly composed of aliphatic compounds, with aromatic compounds being relatively few. High-temperature simulated distillation showed that KVR had a broad boiling-range distribution, with the temperature corresponding to a cumulative recovery of 86.4% exceeding 720 °C, indicating the presence of a certain proportion of ultra-high-boiling components in KVR. The Coats–Redfern kinetic model shows significant variations in activation energy (Ea) at different temperature ranges and reaction orders. Kinetic studies using non-model methods show smaller differences in Ea derived from four different non-model methods. Overall, KVR’s pyrolysis process is complex, with Ea ranging between 100 and 300 kJ/mol.
Li et al. (Wed,) studied this question.