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

0933734约翰智力优点：拟议的研究是针对多功能颗粒的设计，有效地修复氯代烃，如三氯乙烯（TCE）。这些碳氢化合物在地下水和土壤中形成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，会在沉积物中沉淀，并逐渐渗入含水层，造成长期的环境污染。我们将开展研究，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。碳作为吸附剂螯合TCE并将污染物带到反应位点，而NZVI是反应位点。通过吸附可生物降解的纤维素羧甲基纤维素的冠来增强胶体稳定性。这项研究的新奇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、运输和稳定性结合起来。这项工作与早期的工作不同，因为补救的所有方面都是通过使用这些系统同时考虑的。如果成功，它将导致对氯化烃补救的基本理解，并将改变该领域，因为所使用的材料可以调整以实现最佳反应性和运输。更广泛的影响：从科学和技术的角度来看，研究的更广泛影响显然在于应用于一个非常重要的环境问题。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的事实使得它们极难通过传统的泵送和处理或沉积物挖掘技术进行补救。这个问题是为世界人口提供充足安全饮用水这一全球重大挑战问题的内在问题。 这项研究有可能成为真正的变革，因为它提出了一种独特的方法来开发用于环境修复的多功能纳米材料。从教育和推广的角度来看，该项目将配合从代表性不足的少数民族的本科生提供研究机会，通过路易斯安那州少数民族参与研究计划联盟。此外，我们还将与杜兰大学、泽维尔大学和努涅斯学院之间的一个独特项目联系起来，通过合作来提高化学科学的教育水平，目的是解决该地区熟练劳动力的招聘和保留问题。

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.