摘要：IM-5 zeolite is a high-silica shape-selective zeolite that is expected to replace ZSM-5 in some petrochemical process. Herein, highly crystalline mesoporous IM-5 was successfully prepared by alkaline treatment, and changes in the structure and acid properties were characterized using XRD, XRF, XPS, SEM, TEM, N-2 physical adsorption, Py-IR, Si-29 NMR and Al-27 NMR. The Si-29 and Al-22 MAS NMR characterization results indicate that the Si(4Si,0Al) units were preferentially removed from the IM-5 framework during the alkaline treatment, and a small amount of the framework Al was eluted. Meanwhile, desilication and dealumination during the treatment resulted in the loss of strong acid sites. Under optimal conditions, the mesopore volume of mesoporous IM-5 increased relatively by 178% from 0.112 cm(3) g(-1) of the untreated IM-5 to 0.311 cm(3) g(-1), while the micropore volume decreased slightly, indicating its microporous structure was mostly preserved. Although introducing mesopores decreased the acid amount of IM-5, it possessed better diffusion performance. Thus, mesoporous IM-5 exhibited higher light olefins yield (especially propylene) and catalyst lifetime in catalyzing n-alkane than conventional IM-5 and ZSM-5. Furthermore, the higher gasoline yield and lower coke yield over mesoporous IM-5 were obtained than conventional IM-5 in the heavy oil cracking. Interestingly, compared with ZSM-5 with the same SiO2/Al2O3 ratio, the higher acid strength and more B acid site give IM-5 better catalytic performance with higher catalytic activity and higher yields for light olefins and i-butane.

关键字：Alkaline treatment Desilication Mesoporous IM-5 Higher propylene yield

ISSN号：1387-1811

卷、期、页：卷: 273 页: 297-306

发表日期：2019-01-01

影响因子：3.615000

期刊分区（SCI为中科院分区）：二区

收录情况：SCI（科学引文索引印刷版）,ESI（基本科学指标数据库）,EI（工程索引）,SCIE（科学引文索引网络版）

发表期刊名称：Microporous and Mesoporous Materials

通讯作者：余倩倩,孙厚祥,孙厚祥,李磊

第一作者：朱小春,任申勇,郭巧霞,申宝剑

论文类型：期刊论文

论文概要：余倩倩,孙厚祥,孙厚祥,李磊,朱小春,任申勇,郭巧霞,申宝剑，Highly mesoporous IM-5 zeolite prepared by alkaline treatment and its catalytic cracking performance，Microporous and Mesoporous Materials，2019，卷: 273 页: 297-306

论文题目：Highly mesoporous IM-5 zeolite prepared by alkaline treatment and its catalytic cracking performance