CAREER: Synthesis, Characterization and Catalytic Evaluation of Novel Dealuminated Zeolite-based Catalysts for the Alkylation of i-Butane with 2-Butene

提案题目：新型脱铝沸石基i-丁烷与2-丁烯烷基化催化剂的合成、表征及催化评价。ZSM-12是一种大孔、一维、高硅、12元环沸石，将用于研究i-丁烷与2-丁烯的烷基化反应。由于低结焦形成，期望具有高稳定性，而本研究的目标是了解结焦机理和导致稳定性的沸石特征。将研究结构选择铝的脱铝作为改善抗结焦性能的一种手段。为此，将利用L型沸石，它含有连接大腔的长通道。分子筛腔内产生的5-溴甲基间邻苯二甲酸二聚体会影响通道与腔间连接处铝的选择性脱铝。二聚化反应将由合适的自由基引发剂引发。分子筛的表征将包括x射线衍射、27Al NMR（区分框架Al和非框架Al）、SEM、吸附碱红外光谱（确定Bronsted和Lewis酸度）、XPS（区分框架Al的类型）、氨TPD（测量它们的酸度）和EXAFS（研究Al的配位和位置）。从L型沸石的通道-腔交叉处去除Al将用环戊烷异构化来评估。用重量法和质谱法对可溶焦炭的焦化机理进行了研究，并对其烷基化机理进行了动力学研究。该研究对燃料工业具有重要意义，并导致环境友好的过程。

ABSTRACT Proposal Title: Synthesis, Characterization and Catalytic Evaluation of Novel Dealumination Zeolite-based Catalysts for the Alkylation of i-Butane with 2-Butene. Proposal Number: CTS-9702081 Principal Investigator: Panagiotis Smirniotis Institution: Univ. of Cincinnati Dealuminated ZSM-12, a large-pore, one-dimensional, high-silica, 12-member ring zeolite, will be studied for the alkylation of i-butane with 2-butene. High stability is expected as a consequence of low coking formation, and it is the goal of this research to understand the coking mechanism and the zeolite features leading to stability. Dealumination of structurally selected Al will be studied as a means to improve anti-coking behavior. For this purpose, zeolite L, which contains long channels connecting large cavities, will be utilized. Selective dealumination of Al at channel-to-cavity connections will be effected by the dimer of 5-bromomethyl-m-phthalic acid produced inside the zeolite cavity. The dimerization will be initiated by a suitable radical initiator. Characterization of the zeolite will involve X-ray diffraction, 27Al NMR to distinguish framework from non-framework Al, SEM, infrared spectroscopy of adsorbed bases to determine Bronsted and Lewis acidity, XPS to distinguish types of framework Al, ammonia TPD to measure their acidity, and EXAFS to investigate Al coordination and location. The removal of Al from channel-cavity intersections in zeolite L will be assessed with cyclopentane isomerization. The coking mechanism will be studied by gravimetry and by mass spectrometry of soluble coke, and the alkylation mechanisms will be studied kinetically. The research is significant to the fuel industry and leads to environmentally benign processes.