کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5418508 | 1506950 | 2008 | 6 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Structure and hydrothermal stability of Re(VII)-Oxo species grafted onto H-ZSM-5: A DFT study
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله

چکیده انگلیسی
Density functional theory (DFT) was used to assess the potential ReOx structures grafted onto H-ZSM5 by estimating the bond lengths, angles and vibrational spectra of possible Re-Oxo species. The interaction between water molecule and Re-ZSM-5 was investigated for the hydrothermal stabilities of Re-ZSM-5 zeolites at different temperatures. Local structures of one and two H2O molecules adsorbed on the Re-ZSM-5 zeolites reveal that the adsorption mode is changed, when the second H2O molecule is adsorbed. The tetrahedral Re-Oxo center is slightly distorted by the adsorbed water, and the Raman spectra calculated from the optimized structure shift accordingly. The absorption energy Ead is â23.47 and â33.88Â kcal/mol for one and two H2O molecules adsorbed on the Re-ZSM-5, respectively. In addition, the calculated thermodynamic results show that Re-ZSM-5 zeolites are very stable at high temperatures.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Structure: THEOCHEM - Volume 851, Issues 1â3, 28 February 2008, Pages 207-212
Journal: Journal of Molecular Structure: THEOCHEM - Volume 851, Issues 1â3, 28 February 2008, Pages 207-212
نویسندگان
Bingjing Ding, Shiping Huang, Wenchuan Wang,