الفهرس 
Chapter IOnly 14 pages are availabe for public view
 |  | from | 192 |  |  |
| | | from | 192 | | |
Abstract
In this work, we have studies catalytic production of biodiesel from biomass. The thesis includes three chapters, beside Arabic and English summaries and a list of references is also given. The three chapters can be summarized as follows:
Chapter (I) presents general introduction about energy and its related challenges, biomass conversion routes, biodiesel production, characterization of biodiesel, properties of biodiesel, catalysts (homogeneous, heterogeneous and enzyme), solid catalysts (acids and bases), metal organic framework (MOFs). Synthesis, characterization, activation, stability and applications of MOFs in adsorption, membrane separation and catalysis are highlighted.
Chapter (II) includes the experimental and theoretical methodologies used in this work. It illustrates the materials and used chemicals, catalyst preparations, apparatus and characterization techniques of catalysts, the tools utilized for the identification of materials such as X-ray diffraction (XRD), N2 sorption, Fourier transform infrared (FTIR) spectroscopy, pyridine FT-IR, scanning electron microscopy (SEM), liquid dynamic scattering (LDS), nuclear magnetic resonance (NMR), thermogravimetric analysis and temperature programmed desorption (TPD) analysis of NH3 and CO2, the catalytic activity evaluation (esterification reaction of fatty acid) and reusability of catalysts. In addition to the theoretical study of a series of UiO-66(Zr)-structured materials to know the effect of the various functional groups attached to the BDC-linker on the electronic density of zirconium metal.
Chapter (III) gives the results and their discussion. It is classified into two parts as follows:
Part (I) presents the a series of UiO-66(Zr)-structured materials with defects prepared through green method and used as heterogeneous solid catalysts for esterification reaction of oleic acid to yield mono alkyl ester (biodiesel). The prepared catalysts are identified by X-ray diffraction (XRD), N2 sorption, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and temperature programmed desorption (TPD) analysis of NH3 and CO2. Additionally, the influence of reaction conditions such as reaction time, reaction temperature, methanol/acid molar ratio and catalyst loading on catalytic performance was investigated. Also, the kinetic and thermodynamic properties of the reactions involved were investigated and discussed.
Part (II) includes the obtained results on the fabrication of UiO-66(Zr) with various surface hydrophobicities by green approach to elucidate the influence of the environment surrounding Lewis acid sites on their catalytic activity for the esterification of fatty acid at 298 K with excellent recyclability. A detailed structural analysis of these materials by N2 sorption, pyridine FT-IR, powder-XRD, SEM, water contact angle, dynamic liquid scattering (DLS), TGA and Fourier-transformed infrared (FT-IR) revealed the fabrication of UiO-66(Zr) catalysts grafting stearic acid (SA/UiO-66) with a fine particle size and highly hydrophobic network. SA/UiO-66(Zr) in a highly hydrophobic nature exhibited excellent catalytic performance for the esterification of fatty acid with a long alkyl chain, whereas not only conventional solid acid catalysts but also liquid acids showed quite low and the same catalytic activity. Detailed kinetic studies corroborated that the adsorption of lipophilic acid at the Lewis acid site beside the wettability enhancement between reactants was facilitated by hydrophobic environment, thus significantly motivated the esterification reaction at room temperature. Furthermore, SA/UiO-66(Zr)with a highly hydrophobic surface showed excellent catalytic activity for the esterification of oleic acid in the presence of high content of water (~10% in the light of an acid weight).