Novel Molecular Sieve Catalysts Based on Single-walled Carbon Nanotubes

这项研究将推动碳纳米管基材料在多相催化中的应用。碳纳米管是一种具有独特结构、电子、机械和化学性能的新型材料。这组科学家已经开发出一种独特的能力来生产具有可控结构（直径和长度）的大量单壁碳纳米管（SWNT）。该项目将利用这一能力，重点设计用于多相催化剂的独特分子筛支架，该催化剂将具有以下特点：与典型沸石相比直径大，通道长度可调，化学惰性。也有可能调整载体的酸性密度、一维性和增强分子扩散率。为了达到这一目标，将通过改变合成反应温度和选择性氧化去除小直径纳米管来调节SWNT的直径。然后将合成具有不同金属和酸度含量的非均相催化剂，并对两种具有重要工业意义的反应进行测试。它们是烷烃的芳构化和芳烃在硫存在下的氢化。对芳烃的环境担忧导致了限制其处理和运输以及其在柴油和汽油中的含量的法规。要研究的两个过程在最大限度地减少处理芳烃和柴油燃料对环境的影响方面发挥了重要作用。为了扩大研究活动的影响，本科生，高中教师和选定的高中生将参与该项目。在与美国印第安学生协会的合作下，少数族裔工程专业的学生将被选中加入研究项目。

This research will advance the state-of-the-art of carbon nanotube-based materials for applications in heterogeneous catalysis. Carbon nanotubes are a novel material with unusual structural, electronic, mechanical and chemicalproperties. The researchers have developed a unique capability to produce sizeable quantities of single-walled carbon nanotubes (SWNT) with controlled structure (diameter and length). The project will capitalize on this capabilityby focusing on the design of unique molecular sieve supports forheterogeneous catalysts, which would have the following characteristics:large diameter compared to typical zeolites, adjustable channel length, andchemical inertness. There is also the possibility of adjusting the support's aciditydensity, one-dimensionality, and enhanced molecular diffusivity. To reachthis goal, the SWNT diameters will be adjusted by modifying the synthesisreaction temperature and by selectively removing small diameter nanotubes bypreferential oxidation. Heterogeneous catalysts will then be synthesized with varying metal and acidity contents and tested for two reactions of great industrial importance. These are the aromatization of alkanes and the hydrogenation of aromatics in the presence of sulfur. Environmental concerns about aromatics have resulted in regulation that limit their handling and transportation as well as their content in diesel fuels and gasolines. The two processes to be investigated play an important part in minimizing the environmental impact of handling aromatics and diesel fuels. In order to broaden the impact of the research activities, undergraduate students,high-school teachers and selected high school students will participate inthe project. In collaboration with the American Indian Student Association,minority Engineering students will be selected to join the research program.