Butane-butylene fraction cracking over modified ZSM-5 zeolite.

The effect of temperature (530-590°C), weight hourly space velocity (2.5-7.0 h), and the Si/Al ratio of the ZSM-5 zeolite (30, 55, 80, 300) on the cracking of a butane-butylene fraction containing 85 wt % butylenes has been studied. The HZSM-5 zeolite has been modified with phosphorus. The effect of modification on the catalyst activity in cracking reactions has been studied. The ethylene and propylene yield achieves 38.4 wt % at a degree of conversion of butylenes of 81.5%. The ethylene to propylene ratio is 0.55. [ABSTRACT FROM AUTHOR]