牟中原臺灣大學：化學研究所王榮輝Wang, Jung-HuiJung-HuiWang牟中原指導2007-11-262018-07-102007-11-262018-07-102004http://ntur.lib.ntu.edu.tw//handle/246246/51952研究鋁活化不同形貌的硫酸鋯觸媒之催化活性及酸性鑑定Promotion of sulfated zirconia with alumina improved the efficiency and stability of sulfated zirconia catalysts in n-butane isomerization, with a more substantial effect when the promoter was introduced via impregnation on as-synthesized MCM-41, zirconia nanoparticles, and mesoporous sulfated zirconia. The addition of small amount of alumina dramatically enhances the catalytic activity for n-butane conversion. The increase of activity was determined primarily by the amount of aluminum addition and the temperature of calcination. The reasons are several: first, nano-size carriers can help better the dispersion of sulfated tetragonal ZrO2. Secondly, the addition of Al can prevent the transformation of tetragonal sulfated zirconia into monoclinic sulfated zirconia. Thirdly, according to the results of catalytic activities and characterization of acid sites, the remarkable activity and stability of the Al-promoted catalysts are due to a different distribution of acid sites strength and to an enhanced amount of weak Brønsted (II) acid sites with intermediate strength on the optimal catalysts. According to the mechanisms of n-butane isomerization, product distribution is related to the reaction path. The overall reaction mechanism of the isomerization of n-butane over sulfated zirconia was considered and demonstrated three assumptions: (1) The bimolecular mechanism is the major pathway over the “Brønsted (I)” acid sites in the initial period. (2) The “Brønsted (II)” acid sites play an important role via unimolecular mechanism to maintain the steady conversion in the subsequent period. (3) Furthermore, the contribution of Lewis acid sites is negligible.Table of Contents Chapter 1 Introduction……………………………………………1 Chapter 2 Experimental Section…………………………………8 Section 2.1 Chemical Reagents……………………………8 Section 2.2 Synthesis and Preparation of Catalysts………10 2.2.1 Synthesis of MCM-41 Using C16TAB as Template……10 2.2.2 Preparation of ASZ/MCM-41 Catalysts………………10 2.2.3 Synthesis of Sulfated Zirconia Nanoparticles……12 2.2.4 Preparation of ASZ-NP Catalysts……………………12 2.2.5 Synthesis of Mesoporous Sulfated Zirconia………13 2.2.6 Preparation of AS/MP-ZrO2 catalysts………………14 Section 2.3 Characterization Methods………………………15 2.3.1 X-ray Diffraction……………………………………15 2.3.2 N2 Adsorption/Desorption Measurements…………15 2.3.3 n-Butane Isomerization Reaction…………………16 2.3.4 Determinations of Acidic Amount……………………16 2.3.5 Electron Microscopy Studies…………………………17 2.3.6 X-ray Absorption Spectroscopy………………………18 2.3.7 X-ray Photoelectron Spectroscopy…………………19 2.3.8 NMR Spectroscopy…………………………………… 20 2.3.9 Elemental Analysis……………………………………20 Chapter 3 Results and Discussion……………………………22 Section 3.1 ASZ/MCM-41 Catalysts……………………………22 3.1.1 Characterization………………………………………22 3.1.2 Activity for n-Butane Isomerization……………32 3.1.3 The X-ray Absorption Spectral Analysis…………37 3.1.4 Structure of Acid Sites……………………………44 3.1.5 The X-ray Photoelectron Spectral Analysis……54 Section 3.2 SZA Nanoparticle Catalysts………………… 65 3.2.1 Characterization…………………………………… 65 3.2.2 Activity for n-Butane Isomerization……………73 Section 3.3 ASZ/MP-ZrO2 Catalysts………………………76 3.3.1 Characterization…………………………………76 3.3.2 Activity for n-Butane Isomerization…………83 3.3.3 The X-ray Absorption Spectral Analysis………88 3.3.4 The X-ray Photoelectron Spectral Analysis……90 Section 3.4 Influence of Alumina Addition…………………93 Section 3.5 Influence of Calcination Temperature………99 Section 3.6 Reaction Mechanism and Morphological Effect…111 Chapter 4 Conclusions…………………………………………125 References………………………………………………………1292797148 bytesapplication/pdfen-US鋁活化觸媒催化活性酸性鑑定硫酸鋯NanoparticlesCatalystMCM-41MesoporousAluminaSulfated Zirconiathesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/51952/1/ntu-93-D89223007-1.pdf