Hydrothermal Stabilization of Rich Al–BEA Zeolite by Post-Synthesis Addition of Zr for Steam Catalytic Cracking of n-Dodecane

Abstract

The steam cracking of n-dodecane was performed over Zr-modified BEA zeolite. The parent H−BEA zeolite was modified via Zr introduction following earlier treatment (desilication and dealumination). The procedure allowed for achievement of a Si/Zr molar ratio of 100. The changes in BEA crystallinity were observed by X-ray diffraction. The energydispersive X-ray spectroscopy, Fourier transform infrared spectroscopy (FTIR), and nuclear magnetic resonance studies were used to confirm the quantity and position of Zr particles in the framework. Changes in the catalyst acidity were also monitored using pyridine FTIR. The addition of zirconium to the BEA framework prevents dealumination as a result of presence of steam as well as improved the catalyst lifetime from 30 min to 4 h. Dodecane cracking results showed that the introduction of Zr to the BEA framework after desilication is more efficient to protect framework Al in the presence of steam compared to dealumination post-treatment.

Steam catalytic cracking and lump kinetics of naphtha to light olefins over nanocrystalline ZSM-5 zeolite

“…31) and pyridine-FTIR using a Nicolet-6700 spectrometer. 32,33 2.3 The catalytic cracking reactor apparatus Fig. 1 illustrates the investigation scheme of the ZSM-5(P) and steam-treated ZSM-5(ST) catalysts in the catalytic cracking of dodecane in the absence and presence of steam.…”

Catalytic conversion of heavy naphtha to reformate over the phosphorus-ZSM-5 catalyst at a lower reforming temperature

“…16,17 Moreover, Karakoulia et al utilized Pt–Ni/beta 18 and Pt-/AlSBA-15-BET 19 zeolite for the hydroisomerization of n -octane and a naphtha stream under hydrogen pressure with a lower reaction temperature (260–300 °C) than the conventional catalytic reforming reaction. 20 The moderate acidity of the utilized Pt–Ni/beta-zeolite catalyst improved the octane number of naphtha from 55 to 62. Furthermore, the bimetallic catalyst was found to assist the hydroisomerization reaction.…”

Nano BEA zeolite catalysts for the selective catalytic cracking of n-dodecane to light olefins

“…Thus, the conversion dropped to 11%. Moreover, M. Hassan et al 44 synthesized BEA zeolites with different Si/Al ratios: 6, 12.5, 25, 50, and 100. The synthesized BEA catalysts were modified by desilication, dealumination and then ion-exchanged with zirconium.…”