کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
9617806 | 49174 | 2005 | 6 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
In situ FTIR spectroscopic investigation of active sites and adsorbate interactions in mesoporous aluminosilicate SBA-15 molecular sieves
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی شیمی
کاتالیزور
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
Siliceous mesoporous molecular sieve SBA-15 was synthesized, and incorporated with aluminum via post-synthesis procedures. The type and concentration of hydroxyl groups in siliceous and aluminosilicate SBA-15 as a function of the aluminum content were investigated by in situ Fourier-transform infrared spectroscopy (FTIR) following adsorption of various probe molecules, such as pyridine, 1-hexene, benzene, and crotonaldehyde. The data show that isolated silanol groups on the pore surface of siliceous SBA-15 are the primary sites for aluminum incorporation. While different acid sites were identified in aluminosilicate SBA-15, a strong dependence of acidity/hydrocarbon adsorption capacity on the aluminum content was not observed, primarily due to the fact that the amorphous SBA-15 mesoporous walls lack well-defined tetrahedral symmetry for aluminum as found in crystalline zeolite materials. However, the aluminosilicate SBA-15 still showed activity toward adsorbate adsorption and transformation. At elevated temperatures up to 450 °C, a structural transformation of crotonaldehyde to carbonaceous matter (coke) was observed.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Microporous and Mesoporous Materials - Volume 79, Issues 1â3, 1 April 2005, Pages 235-240
Journal: Microporous and Mesoporous Materials - Volume 79, Issues 1â3, 1 April 2005, Pages 235-240
نویسندگان
Zhaohua Luan, Jay A. Fournier,