Microcalorimetric Studies of Supported Platinum Catalysts for Light Paraffin Conversion Reactions

用吸附微量热法研究了负载型铂和铂/锡催化剂的表面热力学，这些反应对汽油的重整反应，特别是轻质烷烃的脱氢和异构化具有重要意义。选择探针分子来研究与感兴趣的催化反应相关的吸附表面的化学键性质。测量了这些探针分子与表面相互作用时的热变和熵变化。将表面热力学数据与稳态研究、同位素示踪和程序升温脱附的反应动力学数据进行比较，以探索表面热力学和表面动力学之间的相关性。考察了表面热力学与催化剂结构之间的关系。该项目是对表面热力学数据库的重大贡献。这也为催化剂设计中这些数据的实用性提供了一个很好的测试。采用的测试系统对满足《清洁空气法》的新标准有直接影响。

Adsorption microcalorimetry is used to study the surface thermodynamics of supported platinum and platinum/tin catalysts for reactions of importance to the reformulation of gasoline, specifically dehydrogenation and isomerization of light paraffins. Probe molecules are selected to study the chemical bonding properties of the surface for adsorbates relevant to the catalytic reactions of interest. The enthalpic and entropic changes associated with the interactions of these probe molecules with surfaces are measured. The surface thermodynamic data are compared with reaction kinetic data from steady-state studies, isotopic tracing, and temperature-programed desorption to explore correlations between surface thermodynamics and surface kinetics. Relationships between surface thermodynamics and catalyst structure are also examined. This project is a major contribution to the data base on surface thermodynamics. It also provides a good test of the utility of such data in catalyst design. The test system employed has immediate implications in meeting the new standards under the Clean Air Act.