Dehalogenation of chlorinated hazardous organics

氯化有害有机物的脱卤

• 批准号: 6457651
• 负责人: Dibakar Bhattacharyya
• 金额: $ 14.25万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-04-01 至 2002-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6457651
• 关键词: environmental toxicology; halobiphenyl /halotriphenyl compound; halogenation; hazardous substances; iron; method development; reducing agents; toxin metabolism; vitamin B12; waste treatment

The development of highly efficient liquid phase remediation technologies for chlorinated organics and the simultaneous understanding of health and nutrition effects are critical for solving Superfund site problems. Reductive dehalogenation technologies, in contrast to oxidative techniques, are known to provide complete detoxification. Reductive processes (zero-valent iron, vitamin B12) can lead to complete dehalogenation to HC1, water and non-halogenated volatile organics if the degradation pathways are controlled. Understanding and control of the degradation pathways to yield innocuous degradation products in short residence times (less than 1 hour) under ambient temperature conditions has yet to be accomplished. The overall objectives of this work are to study the role of the reductive agent morphology on the product distribution and rate, establish the degradation rates of intermediate byproducts (vinyl chloride is an example), and close the elemental balances (particularly C and C1) around the degradation processes. The reductive agent systems to be investigated are zero-valent iron particles, zero-valent nanoscale metal particles and composites, high surface area/high porosity iron coated composites, and novel immobilized vitamin B12 derivative (electropolymerization) systems. With Vitamin B12 the overall rates can be enhanced by incorporating the active complex in polymer films and by using electrochemical techniques to regenerate the active enter. The role of surface morphology and the development of highly reactive materials to reduce reaction time and to enhance intermediate product degradation rates needs thorough investigation for the development of highly efficient remediation systems. In addition to the development of highly versatile models for chlorinated organics dehalogenation rates, we plan to establish the reactive surface morphology (by ARM and XPS methods) changes as a function of reaction time.

开发氯化有机物高效液相修复技术以及同时了解健康和营养影响对于解决超级基金场地问题至关重要。与氧化技术相比，还原脱卤技术已知可以提供完全的解毒。如果降解途径得到控制，还原过程（零价铁、维生素 B12）可完全脱卤为 HCl、水和非卤化挥发性有机物。尚未完成对降解途径的理解和控制，以在环境温度条件下在短停留时间（小于 1 小时）内产生无害的降解产物。这项工作的总体目标是研究还原剂形态对产物分布和速率的作用，确定中间副产物（以氯乙烯为例）的降解速率，并关闭周围的元素平衡（特别是 C 和 C1）降解过程。待研究的还原剂体系包括零价铁颗粒、零价纳米级金属颗粒和复合材料、高表面积/高孔隙率铁涂层复合材料以及新型固定化维生素B12衍生物（电聚合）体系。对于维生素 B12，可以通过将活性复合物纳入聚合物薄膜中并使用电化学技术再生活性成分来提高总体速率。表面形态的作用以及开发高活性材料以减少反应时间和提高中间产物降解率需要进行彻底的研究，以开发高效的修复系统。除了开发氯化有机物脱卤率的高度通用模型外，我们还计划建立反应表面形态（通过 ARM 和 XPS 方法）随反应时间变化的变化。