Correction of the cracking mechanism ratio in catalytic cracking process to characterize the thermal cracking reaction and realize highly sensitive identification of catalysts

In this work, we have specially carried out the catalytic cracking experiments of heavy distillate oil in the high temperature range of 500~700°C. The composition of dry gas generated in the catalytic cracking process was analyzed, with emphasis on the variation of yield of C₁ and C₂ products. Two cracking mechanism ratios (CMRs) were redefined by replacing the (C₁ + C₂) products in the traditional definition of CMR with CH₄, and the feasibility of using them to characterize the thermal cracking reaction in the catalytic cracking process in the high temperature range was investigated. The results showed that CH₄ was more sensitive to temperature than (C₁ + C₂) and it was feasible and more accurate to use CH₄ instead of (C₁ + C₂) corrected R3 to characterize the thermal cracking reaction in the catalytic cracking process in the high temperature range. In addition, it was found that the corrected R3 had the effect of distinguishing and identifying catalysts.