Theoretical and Experemental Study of Solid Base Nanocatalysts (Metal Oxides) Modified by Ionic Liquids and Kinetics Investigation of Organic Reactions Such as Hillman and Biodiesel in the Presence of These Nanocatalysts

Zobeydi, Rahman | 2019

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  1. Type of Document: Ph.D. Dissertation
  2. Language: Farsi
  3. Document No: 51996 (03)
  4. University: Sharif University of Technology
  5. Department: Chemistry
  6. Advisor(s): Rahman Setayesh, Shahrbanoo
  7. Abstract:
  8. Thermodynamic quantities such as proton affinity (PA) and molecular basicity (GB) for (CaO)n nanoclusters with n=2–16 have been calculated using three computational models of the DFT (B3LYP, M06, PW91, CAM–B3LYP and ωB97XD functionals), MP2, and HF with the cc-PVNZ (n = D and T) basis set in the gas phase. Absolute deviation error (AAD%) indicates that obtained PA and GB values using DFT model and the B3LYP method with mean percentage errors of 0.77 and 0.90 %, respectively, have the higher accuracy than the other methods and models. Owing to the unique physical and chemical properties of ILs, can be used as catalysts, promoters and modifiers of catalyst in many organic reactions. Therefore, thermodynamic parameters for the CaO modified with protic and aprotic ionic liquids in the gas and solution phase have been calculated at the DFT/B3LYP level with a 6-311++G (d, p) basis set. The influence of the ILs cations and anions on the PA and GB in the gas phase and solution at the same level of theory has been investigated. The calculations display that energetic ionic liquid has a high ability to improve the basicity properties of CaO nanocluster. A good linear correlations between these quantities and quantum descriptors such as the molecular electrostatic potential (MEP) and the valence natural atomic orbital energies (NAO) have been obtained. Finally, the mechanism and the kinetics of organic reactions such as Morita–Baylis–Hillman (MBH) and biodiesel in the presence of these catalysts have been investigated both theoretically and experimentally, respectively. Our results indicate that in the presence of ionic liquid, the ionic liquid acts as a shuttle for the proton transfer between species in a lower energy pathway. Different amounts of energetic ionic liquid were immobilized on CaO/SBA15 mesoporous material by modified impregnation method. The structure of the catalyst was characterized by FT-IR, XRD, N2 absorption–desorption measurement, and TG. IL/CaO/SBA15 was very efficient in the transesterification of soybean oil with methanol and gave an approximate 99% biodiesel yield when the reaction was carried out at 150 °C with a 5 wt% catalyst amount at 18:1 methanol/oil molar ratio for 3.0 h
  9. Keywords:
  10. Calcium Oxide Nanocluster ; Density Functional Theory (DFT) ; Ionic Liquid ; Morita-Baylis-Hillman ; Biodiesel

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