الفهرس 
1. INTRODUCTION AND LITERATURE SURVEYOnly 14 pages are availabe for public view
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Abstract
This thesis described the synthesis of H-ZSM-5 zeolites with hierarchical micro-meso- porosity (HM-ZSM-5-x) via the soft-templating route, employing organosilane surfactant, 3-[(trimethoxysilyl) propyl]octyldimethyl-ammonium chloride, as the mesoporous template. Many techniques were conducted to characterize the catalysts. The X-ray diffraction and FTIR results affirmed that all mesoporous zeolites possess the characteristic MFI structure, as well as good crystallinity. The N2 physisorption measurements signified that all HM-ZSM-5-x samples have higher surface areas and pore volumes than the micro-ZSM-5 sample, with the mesopores accounting for the vast majority of the total surface areas and pore volumes of HM-ZSM-5-x samples. Moreover, the mesoporosity of the obtained HM-ZSM-5-x zeolites can be simply tuned via the variation of the amount of TPOAC used.
The zeolite sample HM-ZSM-5-0.15 molecular sieve was sulfonated with different amounts (10 – 50 wt%) of 3-MPTES to obtain a series of catalysts with different surface acidities. The characterization results confirmed the successful sulfonation of the zeolite sample. The catalytic property of the sulfonated mesostructured molecular sieves was evaluated in the esterification of oleic acid with methanol to produce biodiesel. The effect of the sulfonation degree and operating conditions on the catalytic performance were investigated. The HM-ZSM-5-0.15-40SO3H catalyst was very efficient for the reaction, achieving a high oleic acid conversion of 99% when the reaction was under the optimum reaction conditions of 5 wt% catalyst dose and methanol: oleic acid molar ratio of 15:1 for 4 hours at 60 °C. More importantly, the HM-ZSM-5-0.15-40SO3H catalyst is stable and can be reused several times with minimal loss of catalytic activity. The HM-ZSM-5-0.15-40SO3H exhibited excellent recyclability and reusability up to 5 consecutive catalytic runs, retaining 50% of the original activity. Ultimately, we explored the performance of the HM-ZSM-5-0.15-40SO3H catalyst for producing biodiesel from a real waste cooking oil, and a high yield of 92.45% was obtained. The results confirmed the high potential of the HM-ZSM-5-0.15-40SO3H catalyst for biodiesel production.
Moreover, the zeolite sample with the largest mesoporosity among the hierarchical zeolite samples, HM-ZSM-5-0.15, was examined as a solid acid catalyst for isomerization of o-xylene in a fixed-bed reactor at atmospheric pressure. Compared with classical micro-ZSM-5, the HM-ZSM-5-0.15 sample possessed a higher o-xylene conversion and p-xylene yield that was attributed to its remarkable textural characteristics in terms of higher surface area and prevailing mesoporous character that led to a reduced diffusion limitation. Importantly, the catalyst manifested superb operational stability within 50 h, indicating high resistance against deactivation through coke deposition.