The Design of Multifunctional Colloidal Nanostructures for Environmental Remediation of Chlorinated Hydrocarbons

智力优势：该研究旨在设计多功能颗粒，有效地修复氯化碳氢化合物，如三氯乙烯（TCE）。这些碳氢化合物在地下水和土壤中形成了一类难以修复的致密非水相液体（DNAPL）污染物。它们的密度比水大，沉降到沉积物深处，逐渐渗入含水层，造成长期的环境污染。将进行研究，以了解基于将零价铁纳米颗粒（NZVI）附着在高度均匀的碳微球上的复合颗粒开发背后的基础科学和技术。碳作为吸附剂对TCE进行吸附，将污染物带到反应部位，而NZVI则是反应部位。胶体稳定性通过吸附可生物降解的聚电解质，羧甲基纤维素的电晕而增强。这项研究的新颖之处在于，通过使用一种可能对环境无害的简单而廉价的系统，将反应、吸附、运输和稳定性耦合在一起。这项工作不同于早期的工作，因为通过使用这些系统同时考虑了补救的所有方面。如果成功，它将导致对氯化烃修复的基本理解，并将改变该领域，因为所使用的材料可以调整为最佳的反应性和运输。更广泛的影响：从科学和技术的角度来看，研究的更广泛的影响显然在于应用于一个重要的环境问题。氯化碳氢化合物是地下水和沉积物中普遍存在的污染物，它们在含水层中向下迁移，这使得它们很难通过传统的泵和处理或沉积物挖掘技术进行修复。这个问题是向世界人口提供足够的安全饮用水这一全球大挑战的内在问题。这项研究具有真正变革的潜力，因为它解决了一种独特的方法来开发用于环境修复的多功能纳米级材料。从教育和推广的角度来看，该项目将通过路易斯安那州少数民族参与研究项目联盟，为未被充分代表的少数民族本科生提供研究机会。此外，我们将与杜兰大学、泽维尔大学和努涅斯学院建立一个独特的项目，通过合作提高化学科学方面的教育水平，以解决该地区招聘和留住熟练劳动力的问题。

0933734JohnIntellectual Merit:The proposed research is directed towards the design of multifunctional particles that are effective in the remediation of chlorinated hydrocarbons such as trichloroethylene (TCE). These hydrocarbons form a class of dense non-aqueous phase liquid (DNAPL) contaminants in groundwater and soil that are difficult to remediate. They have a density greater than water and settle deep into the sediment from which they gradually leach out into aquifers causing long term environmental pollution.Research will be conducted to understand the fundamental science and technology behind the development of composite particles based on attaching zerovalent iron nanoparticles (NZVI) to highly uniform carbon microspheres. The carbon serves as an adsorbent to sequester TCE and bring the contaminant to the site of reaction, while the NZVI is the reactive site. Colloidal stability is enhanced by adsorbing a corona of a biodegradable polyelectrolyte, carboxymethyl cellulose. The novelty of the research is the coupling of reaction, adsorption, transport and stability through the use of a simple and inexpensive system that is potentially environmentally benign. The work is distinct from earlier work in that all aspects of remediation are concurrently considered through the use of these systems. If successful, it would lead to a fundamental understanding of chlorinated hydrocarbon remediation, and would transform the field since the materials used can be tuned for optimal reactivity and transport. Broader Impacts: From a scientific and technical perspective, the broader impacts of the research clearly lie in the application to an environmental problem of significant importance. Chlorinated hydrocarbons are pervasive pollutants in groundwater and sediments and the fact that they migrate downwards in aquifers makes them extremely difficult to remediate through traditional pump and treat or sediment excavation techniques. The problem is intrinsic to the global grand challenge problem of providing adequate safe drinking water to the worlds population. The research has the potential to be truly transformative as it addresses a unique methodology to develop multifunctional nanoscale materials for environmental remediation. From an educational and outreach perspective, the project will tie in to providing research opportunities for undergraduates from underrepresented minorities, through the Louisiana Alliance for Minority Participation in Research program. Additionally, we will tie in to a unique program connecting Tulane, Xavier and Nunez College whereby educational enhancement in the chemical sciences is brought about through collaboration, with the objective of addressing the recruitment and retention of a skilled workforce in the region.