On the synthesis and catalytic cracking properties of Al-ITQ-13 zeolites

• Published in: Microporous and mesoporous materials 2017-07, Vol.246, p.186-192
• Main Authors: Zeng, Penghui, Guo, Xiaozhong, Zhu, Xiaochun, Guo, Qiaoxia, Wang, Yandan, Ren, Shenyong, Shen, Baojian
• Format: Article
• Language: English
• Subjects: 1-Butene catalytic cracking; Al-ITQ-13; Si/Al ratio; Synthesis; Zeolite
• ISSN: 1387-1811; 1873-3093
• DOI: 10.1016/j.micromeso.2017.03.033

Al-ITQ-13 zeolites with different Si/Al atom ratios above 25 were successfully synthesized in short crystallization time by using seeds in the gel. A variety of synthesis conditions were investigated in-depth and the resultant zeolite samples were characterized by XRD, SEM, N2 physisorption and FTIR spectra. Al-ITQ-13 zeolite samples synthesized with different Si/Al ratios exhibit similar textural properties. The amount and strength of acid sites decrease with increasing Si/Al ratio of Al-ITQ-13 zeolites. It was found that H-Al-ITQ-13 samples with low Si/Al ratios show a very high B/L ratio (such as 2.40) at a desorption temperature of 573 K. 1-Butene cracking reaction over proton form Al-ITQ-13 zeolites (Si/Al atom ratio from 47 to 179) was carried out in a continuous flow stainless steel reactor. It was found that the higher of the aluminium content in Al-ITQ-13 (i.e. lower Si/Al ratio), the better selectivity for ethylene and propylene yield. While the hydrogen transfer reaction and alkylation reaction were suppressed with increasing Si/Al ratio. [Display omitted] •Al-ITQ-13 with Si/Al ratios above 25 were synthesized in short crystallization time.•Al-ITQ-13 with low Si/Al ratios show a very high B/L ratio, such as 2.40, at 573 K.•Higher Al content of Al-ITQ-13 show higher propylene yield in 1-butene cracking.•H-transfer and alkylation reaction were suppressed with increasing Si/Al ratio.