Chloro-Organic Degradation by Nanosized Metallic Systems

纳米金属系统降解氯有机物

• 批准号: 7311930
• 负责人: Dibakar Bhattacharyya
• 金额: $ 22.63万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7311930
• 关键词: chelating agents; chemical reaction; chlorination; detoxification; electrochemistry; environmental contamination; environmental protection; halobiphenyl /halotriphenyl compound; hydrogen peroxide; hydroxyl radical; nanotechnology; oxidation reduction reaction; trichloroethylene; waste treatment

Versatile technologies are required for the development of effective dechlorination techniques of hazardous organics utilizing both oxidative and reductive pathways. Chlorinated organics range from chloroethylenes (such as the degreasing solvent, trichloroethylene, TCE), chlorophenols, polychlorinated biphenyls (RGBs), etc. Many chlorinated organics are toxic even at low concentrations, and exert a cumulative, deleterious effect on the environment. The overall objective of this proposal is to develop iron-based oxidative (with Fe(ll) chelates) and reductive (zero valent Fe with dopants such as, Ni, Pd) platforms suitable for highly effective remediation strategies for selected chloro-organic detoxification (PCB's and TCE). Our recent research work has shown the benefits of chelate-modified hydroxyl radical-based oxidative reaction and nanosized zero valent metals for reductive dechlorination. The fundamental understanding of these reactive systems is critical for sustainable use involving remediation. For the oxidative systems, the proposed research will examine in-situ generation of hydrogen peroxide by enzymes, immobilization of polychelates (such as poly-acrylic acid) on inert particles for controlled release of Fe(ll), which is needed for hydroxyl radical formation, and control of dechlorination rates. The reductive platform will examine synthesis of nanosized Fe/Ni and Fe/Pd bimetallic systems using chemical reductants (such as borohydride) and by a novel particle formation method using electrochemical technique within conducting polymers. The proposed research will require several studies involving development of materials, reagent immobilization techniques, quantification of surface morphology, parent compound and intermediates analysis for establishing reaction rates and carbon balance closure, and reaction kinetic parameters for remediation needs. Since hazardous waste and Superfund sites often contain mixture of organics the simultaneous development of both oxidative and reductive remediation techniques should provide more flexibility and tractable approaches.

开发利用氧化和还原途径对有害有机物进行有效脱氯的技术需要多种多样的技术。氯化有机物的范围从氯乙烯（如三氯乙烯，三氯乙烯，三氯乙烯），氯酚，多氯联苯（RGBs）等许多氯化有机物是有毒的，即使在低浓度，并施加累积，对环境的有害影响。该提案的总体目标是开发基于铁的氧化性（具有Fe（II）螯合物）和还原性（具有掺杂剂如Ni、Pd的零价Fe）平台，其适用于所选氯有机解毒（PCB和TCE）的高效修复策略。我们最近的研究工作表明，螯合物改性的羟基自由基为基础的氧化反应的好处， 用于还原脱氯的纳米级零价金属。对这些反应系统的基本了解对于涉及补救的可持续利用至关重要。对于氧化系统，拟议的研究将研究通过酶原位产生过氧化氢，将聚螯合物（如聚丙烯酸）固定在惰性颗粒上以控制Fe（II）的释放，这是形成羟基自由基所需的，并控制脱氯速率。还原平台将研究使用化学还原剂（如硼氢化物）合成纳米级Fe/Ni和Fe/Pd双金属系统，并通过一种新的粒子形成方法，使用导电聚合物内的电化学技术。拟议 研究将需要进行若干研究，涉及材料开发、试剂固定技术、表面形态量化、母体化合物和中间体分析，以确定反应速率和碳平衡闭合，以及补救需要的反应动力学参数。由于危险废物和超级基金场地往往含有有机物的混合物，氧化和还原补救技术的同时发展应提供更多的灵活性和易于处理的方法。