Exploratory Investigation on the Slurry-Phase Hydrocracking Reaction Behavior of Coal Tar and Petroleum-Based Heavy Oil Mixed Raw Material

A petroleum-based atmospheric residue from Merey (MRAR) and a medium-/low-temperature coal tar atmospheric residue (CTAR) were selected as raw materials and mixed in different proportions to form mixed raw materials. The stability of the mixed raw material, product distribution, and properties of coke and asphaltene during the mixed raw material slurry-phase hydrocracking (MSH) reaction were studied to explore the feasibility of co-refining coal tar and petroleum-based heavy oil. The results show that the addition of CTAR can damage the colloidal stability of the mixed system and promote cracking and condensation reactions. However, the destruction degree of system stability was relatively low when the CTAR content was within 40 wt %; the 30 wt % CTAR addition can maximize the raw material conversion rate with moderate increase in coke yield, and both H-2 consumption and light oil yield obtained from the MSH reaction are higher than the theoretical weight value. Thus, it is feasible to perform a co-refining reaction with a certain proportion of CTAR and MRAR. The change trend of the structural parameters such as the micelle size, aromaticity, mean relative molecular mass, and ring numbers of asphaltene after the MSH reaction is closely related to the changes in stability of the mixed raw material, product distribution of the MSH reaction, and properties of coke. Thus, the reaction behavior of MSH can be attributed to a type of synergy between CTAR asphaltene and MRAR asphaltene when CTAR and MRAR are mixed and co-react.