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

智力优势：拟议的研究旨在设计多功能颗粒，以有效修复三氯乙烯(TCE)等氯代烃。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。它们的密度大于水，并深入沉积物，从中逐渐渗出到含水层，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。碳作为吸附剂隔离TCE并将污染物带到反应地点，而NZVI是反应地点。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来增强。这项研究的新奇之处在于，通过使用一种简单且廉价的潜在环境友好的系统，将反应、吸附、传输和稳定性耦合在一起。这项工作与以前的工作不同，因为通过使用这些系统同时考虑补救的所有方面。如果成功，它将导致对氯代烃修复的基本理解，并将改变这一领域，因为所使用的材料可以进行调整，以实现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，这项研究的更广泛的影响显然在于将其应用于一个重要的环境问题。氯代烃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的事实使它们极难通过传统的抽水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安全饮用水这一全球重大挑战问题的内在问题。这项研究具有真正变革性的潜力，因为它解决了开发用于环境修复的多功能纳米材料的独特方法。从教育和外联的角度来看，该项目将通过路易斯安那州少数民族参与研究联盟计划，为来自代表不足的少数民族的本科生提供研究机会。此外，我们将与一个连接杜兰、泽维尔和努涅斯学院的独特计划相结合，通过合作促进化学科学方面的教育，目标是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.