Catalytic cracking of C4 alkenes to propene and ethene: Influences of zeolites pore structures and Si/Al2 ratios

Maximizing propylene production via FCC technology

“…These hydrogen transfer reactions lead to the production of more dry gas, such as methane and ethane, leading to a drop in the selectivity of light olefins. It is thought that a smaller crystal size in combination with high Si/Al ratio gives higher light olefins yields due to lower residence time of primary products in the pores of the catalyst in contact with the acid sites [109]. The stability of the catalyst is also affected by the Si/Al ration especially in relation to coke formation.…”

“…Zhu [109] studied the effect of pore size on hydrogen transfer activity and from their results, they showed that hydrogen transfer activity decreases as the pore size of the zeolite decreases. For the zeolite studied, they showed that the HTI decreased in the following order:…”

SAPO-11/HBeta composites for catalytic cracking of 2-butylene: effects of defect structure

“…Wang et al [3] found that ZSM-23 (SiO 2 /Al 2 O 3 = 30) showed the maximal yield of C 2 -C 3 olefins among the investigated samples during catalytic cracking of butylene, due to one of possible reasons that ZSM-23 (SiO 2 /Al 2 O 3 = 30) had the higher B acidity than the other catalysts. Zhu et al [4,5] observed that the higher selectivity of C 2 -C 3 olefins could be obtained on ZSM-5 zeolite catalyst with higher B acidity. Zhao et al [6] found that ZSM-48 exhibited more excellent selectivity to propylene than ZSM-5 during catalytic cracking of C 4 olefins.…”

“…80% conversion of 2-butylene at 873 K and WHSV = 2.5 h -1 . Zhu et al [4,5] considered that among ZSM-5, ZSM-22, ZSM-23, ZSM-35, SAPO-34 and MCM-22, the smaller the pore size of the molecular sieve was, the higher the initial selectivity of C 2 -C 3 olefins. In order to obtain high selectivity and yield of C 2 -C 3 olefins in catalytic cracking of C 4 olefin, it is necessary to develop new catalytic material and deeply understand its structure-function relation.…”

“…Catalytic cracking of C 4 olefin to propylene and ethylene has attracted much attention because it is an alternative route to produce valuable chemical from cheap resource whether by using fixed bed reactor or FCC reactor system [1][2][3][4][5][6]. Up to date, a few zeolitebased catalysts have been developed.…”