کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10244467 47689 2005 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Formation of better catalytically active titanium species in Ti-MCM-41 by vapor-phase silylation
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
Formation of better catalytically active titanium species in Ti-MCM-41 by vapor-phase silylation
چکیده انگلیسی
Calcined Ti-MCM-41 was silylated by trimethylchlorosilane in the vapor phase for 2-9 h. 29Si MAS NMR spectroscopic study showed that Ti-MCM-41 silylated for 2-5 h exhibited a peak at 11 ppm, which was assigned to (CH3)3SiOSi(OSi)3 species. Further silylation of Ti-MCM-41 for 5-9 h gave an additional peak at 5.1 ppm, which was assigned to novel titanium species of (CH3)3SiOTi(OSi)3. Ti-MCM-41 silylated for 5 h showed relatively high activity in hydroxylation of benzene and epoxidation of 1-octene compared with calcined Ti-MCM-41. More important, Ti-MCM-41 silylated for 9 h gave much higher activity than Ti-MCM-41 silylated for 5 h. 29Si MAS NMR spectra showed the presence of the titanium species of (CH3)3SiOTi(OSi)3 in Ti-MCM-41 silylated for 5-9 h, and these can be better catalytically active sites than conventional titanium species in Ti-MCM-41.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Catalysis - Volume 235, Issue 2, 25 October 2005, Pages 423-427
نویسندگان
, , , , , , , ,