EPOXIDATION OF OLEFINS WITH PDMS MEMBRANES CONTAINING ZEOLITE OCCLUDED MANGANESE DIIMINE COMPLEXES

Citation
Pp. Knopsgerrits et al., EPOXIDATION OF OLEFINS WITH PDMS MEMBRANES CONTAINING ZEOLITE OCCLUDED MANGANESE DIIMINE COMPLEXES, Catalysis today, 32(1-4), 1996, pp. 63-70
Citations number
24
Categorie Soggetti
Engineering, Chemical","Chemistry Applied","Chemistry Physical
Journal title
ISSN journal
09205861
Volume
32
Issue
1-4
Year of publication
1996
Pages
63 - 70
Database
ISI
SICI code
0920-5861(1996)32:1-4<63:EOOWPM>2.0.ZU;2-V
Abstract
A new composite catalyst for selective epoxidation of olefins with ter t-butyl hydroperoxide (tBHP) is reported. The catalyst contains mangan ese diimine complexes (cis-Mn bis-2,2'-Bipyridyl), occluded within a N aY zeolite, in turn incorporated in a polydimethylsiloxane membrane (c is-[Mn(bpy)(2)](2+)-NaY-PDMS). The three-step synthesis consists of a Mn2+ exchange of NaY, ligand sorption to form cis-[Mn(bpy)(2)](2+)-NaY and incorporation of the latter in a PDMS membrane. The major differe nces between [Mn(bpy)(2)](2+)-NaY as such and occluded in PDMS are obs erved in the sorption and catalytic characteristics. With the membrane system, the use of a solvent becomes obsolete. Whereas optimal cycloh exene oxidation with [Mn(bpy)(2)](2+)-NaY occurs with hydrogen peroxid e in acetone, tBuOOH proves to be a better oxidant for [Mn(bpy)(2)](2)-NaY-PDMS. The reactions in batch and fed-batch reactors are discusse d. A simple regeneration procedure, monitored by FT-IR spectroscopy is proposed.