Microcalorimetric, Kinetic, and Spectroscopic Studies of Multi-component Catalysts for Dehydrogenation of Light Paraffins

James Dumesic摘要 这项研究是一个正在进行的努力，表明铂和锡负载在钾交换沸石-L表现出高活性和高选择性的异丁烷脱氢以及gmod稳定性在反应条件下的延伸。 这一发现是研究，以阐明碱改性和支持性能的影响，使用反应动力学研究，吸附微量热研究，和光谱研究。 将研究由以下四种组分配制的新催化剂以确定所涉及的效果：（1）作为脱氢催化剂的过渡金属活性（将尝试镍和钯以及铂）;（2）改性后过渡金属（锗和铅以及锡）;（3）碱金属促进剂（钠、铷和铯以及钾），和（4）中性微孔载体。 微量热研究被用来调查的影响，催化剂改性剂上的探针分子与这些多组分催化剂的相互作用。 红外，穆斯堡尔和核磁共振光谱研究进行照亮的催化剂组分的化学状态，以确定其分散，并探测吸附物的性质。 轻质链烷烃的选择性催化脱氢是用于生产由清洁空气法案（Clean Air Act）规定的汽油重新配制所需的含氧化合物的关键使能方法，并且对于轻质烯烃如乙烯和丙烯的生产也是重要的。 ***

James Dumesic Abstract This study is an extension of an ongoing effort that has shown that platinum and tin supported in potassium-exchanged zeolite-L exhibits high activity and high selectivity for dehydrogenation of isobutane as well as gmod stability under reaction conditions. This finding is examined to elucidate the effects of alkali modification and support properties using reaction kinetics studies, adsorptive microcalorimetric studies, and spectroscopic studies. New catalysts formulated from the following four components will be studied to define the effects involved: (1) a transition metal active as a dehydrogenation catalyst (nickel and palladium will be tried as well as platinum); (2) a modifying post-transition metal (germanium and lead as well as tin); (3) an alkali-metal promotor (sodium, rubidium, and cesium as well as potassium), and (4) a neutral microporous support. Microcalorimetric studies are used to investigate the effects of catalyst modifiers on the interaction of probe molecules with these multicomponent catalysts. Infrared, Mossbauer, and nuclear magnetic resonance spectroscopic studies are conducted to illuminate the chemical states of the catalyst components, to determine their dispersions, and to probe the nature of adsorbates. Selective catalytic dehydrogenation of light paraffins is the key enabling process for the production of the oxygenates needed for the reformulation of gasoline as mandated by the Clean Air Act, and is also important for the production of light olefins such as ethylene and propylene. ***