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Title:	Study of conducting polymer nanocomposite of vanadium pentoxide as redox catalyst for oleic acid oxidation and tungsten oxide as acid catalyst for glycerol esterification
Authors:	Khadijehbeigom Ghoreishi (P51617)
Supervisor:	Mohd Ambar Yarmo, Prof. Dr.
Keywords:	Conducting polymer nanocomposite Vanadium pentoxide Redox catalyst Oleic acid oxidation Tungsten oxide Acid catalyst Glycerol esterification Polymeric composites
Issue Date:	17-Jan-2014
Description:	Conducting polymer nanocomposites have provided new and exciting possibilities in the field of materials science. These inorganic-organic combinations often lead to synergistic effects, resulting enhanced properties, making these materials applicable in various fields such as in fuel cell and catalysis. Conducting polymers such as polyaniline (Pani) and polypyrrole (Ppy) seem to be a promising support for the active phase of catalyst. This kind of matrix is useful especially for oxidative-reductive catalysts, in which the catalytic process involves an exchange of electrons between reactants-products and catalyst. The objective of this research is to synthesis, characterize, and evaluate catalytic performance of V2O5-polyaniline nanocomposite for ozonolysis reaction of oleic acid. The results showed that 20% w/w V2O5 on Pani gives the highest redox performance as confirmed by TPR analysis. 20% w/w V2O5 on Pani showed the highest conversion and selectivity to azelaic acid up to 100% and 85%, respectively. The composite of V2O5 and polyaniline provided a novel catalytic platform for a good dispersion of nano size V2O5 particles and enhanced redox properties which made composite with promising catalytic activity. Analysis by XRD showed that the nanocomposite is formed as semi-crystalline, while V2O5 particles are not detected due to small particle size and high dispersion. This nanocomposite is also applied as cathode catalyst in microbial fuel cell (MFC). 20% w/w V2O5 nanocomposite could be a suitable alternative cathode to Pt as it produces approximately 80 % of the power density of Pt electrode. In addition, this research also extended on preparation, characterization, and catalytic performance of WO3-polypyrrole nanocomposite as solid acid catalyst for glycerol esterification with acetic acid. TPD analysis of WO3-Ppy nanocomposite shows medium acidic activity. The activity and selectivity of the catalyst after the reaction are analyzed using GC-FID analysis. The results showed the composite with 20% WO3 loaded exhibited a high activity (98%) and selectivity (70%) to triacetin at 110 °C and also high selectivity (75%) to monoacetin at milder reaction condition (50 °C). The catalytic activity of WO3-Polypyrrole nanocomposite is compared to other solid acids, sulphated and phosphated silica, homogeneous catalysts such as sulphuric acid and phosphoric acid for further investigation. The results indicated that the acidity nature of polypyrrole, Lewis acid, from proton of –NH group played a very important role in activity of the nanocomposite, making it a suitable catalyst for esterification reaction. Besides that, sulphated and phosphated silica are found to be highly active and selective solid acid catalysts for glycerol esterification even at low temperature of reaction (50 °C). The results showed that glycerol esterification with acetic acid conversion increased as follow: H2SO4 (100%) > H3PO4 (99%) > silica with 20% sulphuric acid loaded, SS-20, (98%) > silica with 20% phosphoric acid loaded, PS-20, (83%). These studies suggest that, the solid acid catalytic activity for esterification of glycerol is much dependant on catalyst acidity strength, pore size and surface area.,PhD
Pages:	172
Call Number:	TA418.9.C6 .G495 2014
Publisher:	UKM, Bangi
Appears in Collections:	Faculty of Science and Technology / Fakulti Sains dan Teknologi

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