الفهرس 
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Abstract
A thesis summarized in three fields: adsorption of heavy metals, HDO of vanillin and Suzuki cross coupling. -Project 1: Efficient Removal of Heavy Metals from Polluted Water with High selectivity for Hg(II) and Pb(II) by 2-imino-4-Thiobiuret Chemically Modified MIL-125 Metal-Organic Framework MIL-125 functionalized with 2-imino-4-thiobiuret including different moieties, like nitrogen and sulfur, was successfully prepared and investigated as a high-performing adsorbent for Hg(II) and Pb(II). The bimolecular interactions between the binding sites on the adsorbent surface and adsorbate molecules involved the sharing of electrons due to the strong chelating effects of the sulfur and nitrogen functional groups within the ITB-NIL-125 adsorbent. The high surface area and a wide distribution of adsorptive sites for specific binding, which are important for designing high-performance adsorbents, were confirmed with various characterization methods. The data obtained from the adsorption experiments of heavy metals showed a high adsorption capacity, stability, and selectivity toward mercury at low and high concentrations, with a maximum adsorption capacity of 946.0 ± 22.0 mg g-1 at pH 6. High uptake values for other metal ions, like As(V) at pH 2, and Pb(II) and Cd(II) at pH 6, were reported with sorption capacities of 34.9 ± 1.7, 350.0 ± 4.2, and 68.9 ± 3.9 mg g-1, respectively. The removal of metal ions using ITB-MIL-125 exhibited excellent fitting with the Langmuir isotherm and pseudosecond order kinetic models. - Project 2. Palladium NPs supported on Graphene Acid Surface for Hydrodeoxygenation of Vanillin as Lignin Model of Upgrade Biofuel. Graphene acid-supported Pd nanoparticles were prepared by different reduction methods. The catalytic performances of the four catalysts were investigated for hydrodeoxygenation of vanillin compound. The catalysts were characterized by UV-vis, FT-IR, Raman spectroscopy, XRD, XPS and TEM. The conversion% of vanillin using ~ 3.0 wt% Pd/PRG─COOH catalysts synthesized by 10% H2-He, LIS, MW and 10% H2-Ar (AutoChem) are 99.17, 98, 97.8 and 97%, respectively, after 120 min. To study the influence of H2 pressure, experiments were carried out under 0.4, 0.7 and 1.0 MPa of H2 gas pressure at 90 ºC with conversion 99.2, 96.5 and 94.4%, respectively, after 120 minutes. As temperature raised, conversion of vanillin was close to ~95% and the selectivity to 2-methoxy-4-methylphenol increased 35.1, 68.6, 95.6% at 70, 90 and 110 ºC, respectively. The prepared catalyst illustrated high catalytic activity after the 4th cycle and selectivity towards 2-methoxy-4-methylphenol slightly dropped to 82.8% after the 4th run. - Project 3. GO/Ln-MOFs Supported Pd Nanoparticles for Hydrodeoxygenation of Vanillin as Lignin Model. A polymeric structure of Ln-MOFs based on lanthanides as metal nodes and H3BTC was prepared by the solvothermal method. X-ray crystallography revealed the Ln(III) ions coordinated to seven oxygen atoms, one from terminal water molecule in the distorted monoclinic coordination sphere and six oxygen atoms from a carboxylic group in six different H3BTC linkers. Catalyst Pd/Yb-MOF showed high catalytic activity of vanillin and 98.7% conversion was reached within 360 min compared to other Pd/Ln-MOFs. After the incorporation of GO sheets, the transformation rate of vanillin was enhanced to a maximum of 5.0 wt%. The enhancement of reactivity may be attributed to the good dispersion of Pd nanoparticles within the cavities of the Yb-MOF and the presence of Lewis acid sites from PRGO. The catalytic conversion increased by increasing the pressure of H2 gas, reaction temperature and S/C ratio. - Project 4. Laser Synthesis of Carbonaceous ZrO2 from UiO-66 and UiO-66-NH2: Optimum Support for Pd Nanoparticles for Suzuki Cross-Coupling Reactions UiO-66 and UiO-66-NH2 were prepared by a facile method based on ZrCl3 and organic linkers. The resulted solids were transformed to their oxides under a mixture of O2 in He atmosphere. Laser beam discharges target atoms into the gas phase, which nucleate into nanoparticles and are deposited onto the top plate via convection where they are collected. The produced powders were ZrO2/C and ZrO2/C/N were supported by Pd ions and reduced by laser irradiation in solutions. The catalytic activities of fabricated materials were investigated for the Suzuki cross-coupling reaction of 4-bromotoulene and phenylboronic acid at room temperature. SCC reaction was chosen to study the catalytic activity at room temperature. Pd nanoparticles loaded on UiO-66 and UiO-66-NH2, supports showed high catalytic conversion reached 100% after 45 and 15 min, respectively, due to instability in the basic medium during SCC as MOFs based on M(IV) soluble in a very diluted basic medium. TOF numbers showed that Pd/ZrO2/C/N (LVCC of UiO-66-NH2/1 wt% GO) has the highest catalytic activity with a value of 532,100 h-1 after 30 min reaction time. Four catalysts were selected to investigate activity on the synthesis of different biphenyl products under MWI.