کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
60583 47537 2016 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Hydrothermal stability and catalytic performance of desilicated highly siliceous zeolites ZSM-5
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
Hydrothermal stability and catalytic performance of desilicated highly siliceous zeolites ZSM-5
چکیده انگلیسی


• Desilicated high silica zeolites presented good hydrothermal stability.
• Preservation of mesoporosity after the steaming treatment.
• Mesopores system benefited the diffusion of the bulky molecule in FCC process.

Highly siliceous zeolites, namely MFI type have attracted the great attention due to their higher hydrothermal stability, higher selectivity to organic compounds, and often better catalytic properties in comparison with Al-rich zeolites. The native zeolite (Si/Al = 164) and its desilicated analogues were deeply characterized with regard to their structural and textural properties by X-ray diffraction, low temperature adsorption of nitrogen and solid-state 27Al MAS NMR. Their acidic properties were evaluated in quantitative IR studies. Finally, the catalytic performance of desilicated zeolites ZSM-5 was evaluated in the cracking of n-decane, 1,3,5-tri-iso-propylbenzene and vacuum gas oil. In this article, it is shown that high silica zeolites prepared by NaOH and NaOH&TBAOH leaching presented good hydrothermal stability with only slightly lower resistance when comparing to native steamed zeolite. The mesoporosity was preserved after the steaming treatment. The influence of the generated mesoporosity on the higher activity was evidenced in both 1,3,5-tri-isopropylbenzene and diesel oil cracking of steamed hierarchical zeolites. In spite of their lowered acidity, the mesopores system benefited the diffusion of the bulky molecule and finally provided higher activity of hierarchical zeolites.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Catalysis - Volume 339, July 2016, Pages 256–269
نویسندگان
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