Abstract: In order to find out the structure-activity relationship of the pore structure of molecular sieve and acidity on deep catalytic cracking of hydrocracker tail oil to produce light olefin, and to find the optimal catalyst for the efficient conversion of hydrocracker tail oil, seven kinds of molecular sieves with different topological structures, such as BEA, FER, TON, FAU, AEL, AFI, MFI, were selected to investigate the deep catalytic cracking performance of hydrocracker tail oil on molecular sieves with different pore structures. The effects of acidity of molecular sieve on the reaction performance and the distribution of light olefin products were further analyzed by micro-pulsed reaction using n-hexane as probe. The deep catalytic cracking test of hydrocracker tail oil showed that the conversion rate was affected by both pore size and structure, SAPO-11 molecular sieve with one-dimensional elliptical pore structure of 0.40 nm × 0.65 nm was the best catalyst for deep catalytic cracking reaction, and the higher the amount of weak acid and medium-strong acid in molecular sieve, the more beneficial to the formation of ethylene and propylene.

Key words: deep catalytic cracking, hydrocracker tail oil, zeolite, light olefin, micro-pulsed reactor