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Immobilized catalysts for alkene oxidation

Magister Scientiae - MSc / Tertiary butyl substituted and unsubstituted Schiff base systems containing N,O donor ligands (Salicylaldimines) with aminotriethoxysilane tail were synthesized and complexed to Copper and Cobalt acetate. The ligands were characterized by FTIR and 1 HNMR Spectroscopy. The complexes were characterized by elemental analysis, ESI-Mass spectrometry and IR spectroscopy Mesoporous silica supports (SBA-15 and MCM-41) were synthesized and characterized by Xray
diffraction, BET surface analysis and SEM. The tertiary butyl substituted and unsubstituted copper and cobalt salicylaldimine complexes were immobilized on amorphous
(Davisil silica gel) and mesoporous supports (SBA-15 and MCM-41). Immobilized catalysts were characterized with Atomic Absorption Spectroscopy, X-ray diffraction, BET surface analysis, IR spectroscopy and SEM. Immobilized catalysts were tested for cyclohexene oxidation using molecular oxygen as cooxidant and hydrogen peroxide as oxidant. In this study the effect of metal, reaction time,
nature of oxidant (hydrogen peroxide tertiary butyl hydroperoxide), substituents on the ligand and substrate concentration were investigated. Allylic products were obtained at relatively high cyclohexene conversion. In addition to the above, homogeneous systems were compared
with heterogeneous analogues. The former were found to have better selectivity than their heterogeneous analogues although there appears to be no significant difference in the activity. / South Africa

Identiferoai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:uwc/oai:etd.uwc.ac.za:11394/2441
Date January 2007
CreatorsMalumbazo, Nandi
ContributorsMapolie, S.F., Dept. of Chemistry, Faculty of Science
PublisherUniversity of the Western Cape
Source SetsSouth African National ETD Portal
LanguageEnglish
Detected LanguageEnglish
TypeThesis
RightsUniversity of the Western Cape

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