Mechanisms of Fullerene Synthesis in Flames

该研究计划的主要重点是定量 调查造成这一现象的详细机制 将燃料碳转化为高度对称、低熵 火焰中的富勒烯化合物 该项目包括三 主要组成部分：燃烧实验，分子轨道 建模和动力学建模。 在燃烧 实验，生产率的实验室数据， 富勒烯、富勒烯前体和其他物质的消耗 将收集物种和火焰参数。 火焰 待测量的性质包括浓度分布 稳定物种，富勒烯，富勒烯中间体， 多环芳烃（PAH）沿着与OH自由基 和温度; 这些测量将在各种操作中进行， 压力、冷气速度和进料组成。 一些 富勒烯生产中涉及的关键中间体将不会 由于它们的瞬态性质， 它们的热力学性质将用 分子轨道模拟方法 这些信息将 然后在程序的最后一个组成部分， 开发和动力学建模，沿着测量 发展一个连贯的、定量的 富勒烯生产中涉及的步骤的说明， 从而定义优化的策略， 通过燃烧合成的富勒烯生产。 对富勒烯的极大兴趣（也称为 有时作为碳的第三种形式，与石墨一起， 钻石），在过去的几年里已经发展起来。 潜在 这些化合物的用途才刚刚开始确定; 这种定义和随后实际使用是有限的 由于缺乏工作材料， 非常高的价格。 燃烧合成 富勒烯提供了一种潜在的有吸引力的途径（替代 涉及目前更广泛使用的电弧法， 富勒烯的生产）。 因此，在本发明中， 对富勒烯如何形成的理解的发展 在火焰中，导致优化（在操作方面 燃烧参数和设备配置 这些材料的合成是主要的兴趣。

The primary focus of this research program is the quantitative investigation of the detailed mechanisms responsible for conversion of fuel carbon into highly symmetrical, low entropy fullerene compounds in flames. The project includes three main components: combustion experiments, molecular orbital modeling, and kinetic modeling. In the combustion experiments, laboratory data on rates of production and consumption of fullerenes, fullerene precursors, and other species and flame parameters will be collected. The flame properties to be measured include profiles of concentrations of stable species, fullerenes, fullerene intermediates, and polycyclic aromatic hydrocarbons (PAH) along with OH radicals and temperature through a low-pressure premixed flat flame; these measurements will be made at various operating pressures, cold-gas velocities, and feed compositions. Some key intermediates involved in fullerene production will not be experimentally observable due to their transient nature, so their thermodynamic properties will be estimated using molecular orbital modeling methods. This information will then be used in the last component of the program, mechanism development and kinetic modeling, along with the measured profiles, for development of a coherent, quantitative explanation of the steps involved in fullerene production, leading to definition of strategies for optimization of fullerene production via combustion synthesis. Considerable interest in fullerenes (also referred to sometimes as the third form of carbon, alongside graphite and diamond), has developed over the past few years. Potential uses for these compounds are just beginning to be defined; such definition and subsequent actual utilization are limited by a lack of material with which to work and its extraordinarily high price. Combustion synthesis of fullerenes offers a potentially attractive route (alternative to the currently more widely used electric arc method of fullerene production) for cost and scale-up reasons. Thus, development of an understanding of how fullerenes are formed in flames, leading to optimization (in terms of operating parameters and apparatus configuration) of combustion synthesis of these materials, is of major interest.