Steam catalytic cracking of heavy naphtha (C12) to high octane naphtha over B-MFI zeolite

Abstract

Continues consuming of fuel from fossil oil reservoirs due to the increase in energy demands encouraged scientists to use the pyrolysis of biomass in the production of clean energy. One of the most important product from the pyrolysis of biomass is dodecane. However, dodecane requires a further transformation in order to produce lighter hydrocarbons. Borosilicalite-1 (B-MFI) was synthesized with different mineralizer agents and utilized for steam catalytic cracking of dodecane. Furthermore, the amount of cooperative incorporation of boron to zeolitic framework contributes in adjusting the zeolitic acidity and consequently the amount of weak acid sites were observed to be proportional to the contents of boron. However, from pyridine-FTIR analysis, it was noticed that the acid site nature of borosilicalite-1 samples exhibited Brønsted acid site. Nevertheless, the presence of alkali fluoride as mineralizer agent enhanced the presence of boron in tetrahedral coordination system, which led to lower catalytic activity. While samples synthesized in the presence of alkali hydroxide were catalytically more active in steam catalytic cracking of dodecane due to its exhibit in trigonal coordination system. It was found that borosilicalite-1 was more stable when it was synthesized in the presence of sodium hydroxide as mineralizer agent rather than potassium hydroxide and the conversion was reached to 95% at 350°C with space velocity of 4h−1 when the Si/B ratio was 10.