Targeted chemical modification of the molecular composition of heavy oils is an important way to utilize heavy oils for high-value. Distillation and separation is a common industrial method for extracting raw fractions for needle coke production. However, cracked tars such as catalytic slurry oil are easy to coke and stop working during conventional distillation processes, which are completely different from crude oil straight-run residue, indicating that in addition to colloidal asphaltenes, there are also unconventional unstable molecules. The new technology found that the unconventional unstable molecules that cause coking in distillation are olefins. Through mild selective hydrotreating, not only can the olefin bond be saturated, but also high-boiling condensed aromatic molecules be partially hydrogenated to lower the boiling point. As a result, the depth of non-destructive distillation can be significantly increased and the target fraction is increased, so that the yield and quality of high-value needle coke materials are improved.

 (This achievement was released by the Qingdao Joint Office of Technology Transfer of Universities and Institutions)