RIMI: Titanium Dioxide Catalyzed Photodegradation of Organophosphorous Compounds: A Kinetic and Mechanical Study

RIMI：二氧化钛催化有机磷化合物的光降解：动力学和力学研究

• 批准号: 9550712
• 负责人: Kevin O'Shea
• 金额: $ 14.99万
• 依托单位: Florida International University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-06-01 至 1998-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9550712&HistoricalAwards=false
• 关键词: RIMI; Titanium; Dioxide; Catalyzed; Photodegradation

9550712 O'Shea The Ti02 catalyzed photodegradation of the organophosphorus compounds will be carefully monitored and evaluated to determine the kinetic parameters for the process. These kinetic parameters are of importance in evaluating and predicting overall rates and efficiencies for the degradation of organophosphorus compounds in multi-component systems and for reactor design. The mass balance between the initial substrates and the products formed during these reactions will be used to determine the degree of mineralization. Characterization of the reaction intermediates and products formed throughout the course of the degradation will be used to establish the course of the reactions. Hydroxyl radical, superoxide anion, and hydrogen peroxide are formed during the photocatalytic process, each species will be independently generated and the product distribution upon reaction with the simulants determined. The characteristic product distributions for hydroxyl radical, superoxide anion, and hydrogen peroxide will be compared to those observed for the Ti02 catalyzed photo-reactions to establish the role and involvement of these intermediates in the Ti02 catalyzed photodegradation. Since the solutions pH, dissolved oxygen concentration, and reaction byproducts can dramatically effect the degradation process, these factors will be thoroughly investigated. The use of additives to accelerate the process will also be evaluated. These studies will provide a fundamental understanding of the factors governing the chemical reactivity of organophosphorus compounds on photoexcited TiO2. The information obtained from the proposed investigations will find direct application in the optimization and evaluation of semiconductor catalyzed photooxidation as a means of detoxification of environmentally threatening organophosphorus compounds, such as chemical warfare agents and pesticides. If supported this project will have a substantial impact on the fundamental understa nding of the processes involved in TiO2 photocatalysis and the professional development of several minorities into the chemical and environmental sciences. One minority faculty member, 4-5 undergraduate students (three which currently plan to pursue a Ph.D. in Chemistry upon completion of their BS degrees) and 2 masters students will be directly involved in the proposed project. Support will increases minority participation in the PIs' laboratories by 50%. ***

9550712 O'Shea 将仔细监测和评估 TiO2 催化的有机磷化合物的光降解，以确定该过程的动力学参数。 这些动力学参数对于评估和预测多组分系统中有机磷化合物降解的总体速率和效率以及反应器设计非常重要。 初始底物和这些反应过程中形成的产物之间的质量平衡将用于确定矿化程度。 整个降解过程中形成的反应中间体和产物的表征将用于确定反应过程。 光催化过程中会形成羟基自由基、超氧阴离子和过氧化氢，每种物质都会独立生成，并确定与模拟物反应后的产物分布。 将羟基自由基、超氧阴离子和过氧化氢的特征产物分布与TiO 2 催化光反应中观察到的产物分布进行比较，以确定这些中间体在TiO 2 催化光降解中的作用和参与。 由于溶液 pH 值、溶解氧浓度和反应副产物会显着影响降解过程，因此将对这些因素进行彻底研究。 还将评估使用添加剂来加速该过程。 这些研究将为控制有机磷化合物在光激发 TiO2 上的化学反应性的因素提供基本的了解。 从拟议的研究中获得的信息将直接应用于半导体催化光氧化的优化和评估，作为对环境威胁的有机磷化合物（例如化学战剂和杀虫剂）的解毒手段。 如果获得支持，该项目将对 TiO2 光催化过程的基本理解以及少数群体在化学和环境科学领域的专业发展产生重大影响。 一名少数族裔教师、4-5 名本科生（其中三名目前计划在完成学士学位后攻读化学博士学位）和 2 名硕士生将直接参与该拟议项目。 支持将使少数派在 PI 实验室的参与度增加 50%。 ***