Browsing by Author "Kayuki, Gwido Elliam"

Now showing 1 - 1 of 1
  • No Thumbnail Available
    Item
    Preparation of polymer-supported palladium catalysts for hydrogenation of vegetable oil.
    (University of Dar es Salaam, 2003) Kayuki, Gwido Elliam
    The synthesis of spherical polymer particles and their use for immobilising palladium catalysts is described. Spherical polymer particles (SPP) were prepared using cashew nut shell liquid (CNSL) and formaldehyde by suspension polymerisation. A high viscosity CNSL (1680 cps) was found to be effective in the production of particles while the less viscous (624.17 cps) CNSL was not. The effect of dodecanol and cyclohexanol as porogens on the particle formation and size was studied. Cyclohexanol was found to produce better results; 81% of recipes tried with cyclohexanol were successful while only 21% of those tried with dodecanol were successful. Particle sizes ranged between 0.355 and 2.00 mm in diameter for dodecanol while for cyclohexanol they ranged between 0.500 and 2.00 mm. Several approaches for immobilising palladium metal catalyst on the SPP were attempted. The immobilised catalysts were found to be active in the hydrogenation of cotton seed oil under mild conditions. The catalyst loadings were determined by atomic absorption spectrophotometey and were found to range between 0.000 and 0.097%w/w Pd. The extent of hydrogenation was analysed by determining the iodine value. The catalysts were found to be recyclable. Contamination of the hydrogenated product was found to be too small to be detected by the spectrophotometer. Overall results indicate that the techniques developed in this study lead to an active hydrogenation catalyst.