Environmental Catalysis: Gas Phase Hydrodechlorination of Chlorophenols

环境催化：氯酚的气相加氢脱氯

• 批准号: 0218591
• 负责人: Mark Keane
• 金额: $ 30.91万
• 依托单位: University of Kentucky Research Foundation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0218591&HistoricalAwards=false
• 关键词: Environmental; Catalysis; Gas; Phase; Hydrodechlorination

This proposal sets out a fundamental study that is focused on probing the link between catalytic hydrodechlorination activity/selectivity and catalyst structure. Previous work by the PI has established that nano-dispersed nickel on amorphous silica in the presence of hydrogen is highly efficient in the dechlorination of concentrated chlorinated gas streams; the chlorine that is removed is solely in the form of HCl that is easy to trap. The existing catalyst activity/selectivity database will be extended in a strategic fashion, focusing on the treatment of chlorinated phenols as model reactants; the latter represents a class of commercially significant and highly toxic industrial waste. Preliminary results have revealed that chlorobenzene and chlorophenol hydrodechlorination over Ni/SiO2 is structure sensitive in that larger Ni particles (in the range 1-4 nm) exhibit higher specific dechlorination rates but are more susceptible to deactivation. The issue of catalyst decay will be addressed through a comprehensive program of catalyst characterization before and after reaction. This will involve bulk structural studies (x-ray diffraction), high-resolution transmission electron microscopy (TEM), analytical TEM including EDX and EELS, surface area/porosity measurements, chemisorption/TPD/TPO studies and x-ray photoelectron spectroscopy to probe changes in Ni electronic structure. Moreover, the nature of the reactant(s)/product(s) interaction with the catalyst surface will be probed using spectroscopic (FTIR-DRIFT) and chromatographic techniques. The presence of chlorinated aromatics in industrial effluent is now established as a major source of environmental pollution. This work may form the basis for a more efficient pollution prevention method. The PI has previously worked with both graduate and undergraduate students in an international context. In this project he will also work with chemistry students and provide training in engineering research.

该提案提出了一项基础研究，重点探讨催化加氢脱氯活性/选择性与催化剂结构之间的联系。 PI之前的工作已经证实，在氢气存在下，纳米分散在无定形二氧化硅上的镍对于浓氯化气流的脱氯非常有效。去除的氯仅以易于捕获的 HCl 形式存在。 现有的催化剂活性/选择性数据库将以战略方式扩展，重点关注作为模型反应物的氯化酚的处理；后者代表一类具有重大商业意义和剧毒的工业废物。初步结果表明，Ni/SiO2 上的氯苯和氯酚加氢脱氯具有结构敏感性，因为较大的 Ni 颗粒（1-4 nm 范围内）表现出较高的比脱氯速率，但更容易失活。催化剂衰减问题将通过反应前后催化剂表征的综合程序得到解决。这将涉及体结构研究（X 射线衍射）、高分辨率透射电子显微镜 (TEM)、分析 TEM（包括 EDX 和 EELS）、表面积/孔隙率测量、化学吸附/TPD/TPO 研究和 X 射线光电子能谱，以探测 Ni 电子结构的变化。此外，将使用光谱（FTIR-DRIFT）和色谱技术来探测反应物/产物与催化剂表面相互作用的性质。工业废水中存在的氯化芳烃现已被确定为环境污染的主要来源。 这项工作可能为更有效的污染预防方法奠定基础。 PI 之前曾在国际背景下与研究生和本科生合作过。 在这个项目中，他还将与化学学生合作并提供工程研究培训。