CAREER: On the Prevention of Selenium and Arsenic Release into the Atmosphere

职业：防止硒和砷释放到大气中

• 批准号: 0448758
• 负责人: Jennifer Wilcox
• 金额: $ 39.98万
• 依托单位: Worcester Polytechnic Institute
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-02-15 至 2008-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0448758&HistoricalAwards=false
• 关键词: CAREER; Prevention; Selenium; Arsenic; Release

CAREER: On the Prevention of Selenium and Arsenic Release into the AtmosphereThe goal of the proposed work is to aid in the prevention of the release of the volatile metals, selenium and arsenic, from the flue gases of coal combustion. There have been extensive research efforts aimed at capturing mercury and understanding its speciation in flue gases, but not as much is known of selenium and arsenic in the chemically complex flue gas environment. The proposed research will also examine novel sorbent technologies for the capture of these trace elements, and a mechanism responsible for their retention will be determined. Model development will take place through high level ab initio energetics calculations. The research activities proposed will advance discovery through the development of two kinetic models that will elucidate, for the first time ever, the mechanism of retention of selenium and arsenic on calcium based sorbents. In addition, the proposed plan includes the development of a high school outreach program, which will involve undergraduate students training high school teachers on the incorporation of computational chemistry and molecular modeling techniques into their science courses. The research and educational activities combined will advance understanding through the incorporation of molecular computational applications in the classroom, which will provide both college and high school students the opportunity to gain a deeper understanding of chemical interactions using multimedia-based approaches for effective teaching. Understanding the speciation of selenium and arsenic in the flue gas environment is essential for developing effective technologies to control their emissions. Homogeneous reactions involving these species will be examined through the theoretical prediction of rate constants obtained from quantum mechanical derived potential energy surfaces. Effective core potentials that include relativistic effects will be incorporated into the basis sets, and this will be carried out for all calculations using both Quadratic Configuration Interaction (QCI) and Coupled Cluster (CC) techniques. Heterogeneous reaction investigations will also take place to elucidate the mechanisms responsible for the retention of arsenic and selenium on calcium-based sorbents. Heterogeneous rate constant predictions will be experimentally validated through the analysis of the reacted sorbent material using an Inductively Coupled Plasma Mass Spectrometer (ICP-MS). In total, this research will benefit the scientific community in that there will be a greater understanding of the speciation of these trace elements in the flue gases of combustion processes and also further understanding on methods involving their capture. The impact that the proposed research could have on society is the possible prevention of the release of these toxic elements into the atmosphere.

职业：预防硒和砷释放到拟议工作的目标中，是为了防止燃料的烟气从燃料的烟道气体中预防释放挥发性金属，硒和砷。 已经进行了广泛的研究工作，旨在捕获汞和在烟气中理解其物种形成，但在化学复杂的烟气环境中，硒和砷尚不为众所周知。 拟议的研究还将检查新颖的吸附技术，以捕获这些痕量元素，并确定负责保留的机制。 模型开发将通过高水平的初始能量计算进行。 提出的研究活动将通过开发两个动力学模型来提高发现，这些动力学模型将首次阐明在基于钙的吸附剂上保留硒和砷的机制。 此外，拟议的计划包括制定高中宣传计划，该计划将涉及培训高中教师的计算化学和分子建模技术中的高中教师。 研究和教育活动的结合将通过在课堂中纳入分子计算应用来提高理解，这将为大学和高中生提供机会，以使用基于多媒体的有效教学方法来深入了解化学相互作用。 了解烟气气体环境中硒和砷的物种形成对于开发有效的技术以控制其排放至关重要。 涉及这些物种的均匀反应将通过从量子机械衍生的势能表面获得的速率常数进行理论预测来检查。 包括相对论效应的有效核心电位将纳入基集中，并使用二次配置相互作用（QCI）和耦合群集（CC）技术进行所有计算。 还将进行异质反应调查，以阐明负责在基于钙的吸附剂上保留砷和硒的机制。 异质速率常数预测将通过使用电感耦合等离子体质谱仪（ICP-MS）对反应的吸附材料进行分析来实验验证。 总的来说，这项研究将使科学界受益，因为在燃烧过程的烟道气体中，将对这些痕量元素的物种形成有所了解，并进一步了解涉及其捕获的方法。 拟议的研究可能对社会产生的影响是预防这些有毒因素进入大气中的释放。