preparation and characterization of supported molybdenum and tungsten schiff base complexes on mcm-41 as nanocatalysts for the epoxidation of olefins

نویسندگان

m. masteri-farahani

m. sadeghi

y. abdollahi

m. mehdi kashani motlagh

f. salimi

چکیده

two new heterogenized epoxidation nanocatalysts based on molybdenum and tungsten compounds were prepared withcovalent grafting of mcm-41 with 3-aminoropropyl trimethoxysilane and subsequent reaction with diphenylphosphinobenzaldehyde and complexation with m (mo, w)o2(acac)2. x-ray diffraction and nitrogen sorption analyses revealed the preservation of the textural properties of the support as well as accessibility of the channel system despite sequential reduction in surface area, pore volume and pore size. elemental analyses showed the presence of 0.15 mmol molybdenum and 0.09 mmol tungsten per gram of the catalyst, respectively. epoxidation of olefins in the presence of m (mo,w)o2dppb@ampmcm-41 with tert-butyl hydroperoxide (tbhp) and hydrogen peroxide were examined.

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Preparation and Characterization of Supported Molybdenum and Tungsten Schiff Base Complexes on MCM-41 as Nanocatalysts for the Epoxidation of Olefins

Two new heterogenized epoxidation nanocatalysts based on molybdenum and tungsten compounds were prepared withcovalent grafting of MCM-41 with 3-aminoropropyl trimethoxysilane and subsequent reaction with diphenylphosphinobenzaldehyde and complexation with M (Mo, W)O2(acac)2. X-ray diffraction and nitrogen sorption analyses revealed the preservation of the textural properti...

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immobilization of a molybdenum complex with tetradentate ligand on mesoporous material mcm-41 as catalyst for epoxidation of olefins

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عنوان ژورنال:
journal of nanostructures

ناشر: university of kashan

ISSN 2251-7871

دوره 1

شماره 2 2012

کلمات کلیدی
[ ' t u n g s t e n ' , ' m o l y b d e n u m ' , ' m c m ' , 4 1 , ' s u p p o r t e d s c h i f f b a s e ' , ' e p o x i d a t i o n ' ]

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