CAREER: Reengineering physicochemical properties of carbon nanotubes for enhanced adsorption of disinfection byproduct precursors

CBET-1254350阿肯色州大学Julian Fairey美国饮用水公用事业公司面临的最大挑战可能就是满足三卤代甲烷和卤代乙酸的消毒副产品法规。随着自来水公司继续开采受藻华和废水排放影响的水源，这些受管制的化学品和其他潜在的有毒消毒副产品，如N-亚硝酸二甲胺的形成预计将增加。幸运的是，新兴的纳米技术领域提供了希望。具体地说，碳纳米管的性质表明，它们可能对消毒副产物前体具有相当大的吸附能力，这一能力可以通过操纵碳纳米管表面化学来进一步增强。本研究项目的目的是重新设计碳纳米管的可调物理化学性质，以增强对消毒副产物前体的吸附。将采用系统的还原方法来改变碳纳米管的物理(例如，比表面积、孔径分布)和化学(例如，表面官能团、表面电荷)性质，以增强对三卤代甲烷、卤代乙酸和N-亚硝基二甲胺前体的吸附。重组后的碳纳米管的平衡吸附容量将通过批量等温线实验进行测量。将使用快速小规模柱测试来评估动力学限制，以确定饮用水处理厂内集成碳纳米管的合适工艺。将对直接气化再生废碳纳米管的程度进行评估，以解决成本问题。重新设计的碳纳米管和消毒副产物前体的基本表征(例如，傅立叶变换离子回旋共振质谱仪的元素组成)将促进结构-性质关系的发展，从而使研究结果具有广泛的适用性。这项研究的预期结果是一个系统化的程序，从根本上重新设计碳纳米管，以增强对消毒副产物前体的吸附。美国许多饮用水公用事业公司面临的一个主要挑战是实现足够的消毒，同时限制消毒副产物的形成。由于人口增长的涓滴影响，水变得更加受损，迫切需要在消除消毒副产物前体方面取得重大进展。在这项研究项目中，利用纳米技术、表面化学和分析化学的原理来重新设计碳纳米管，以有效地吸收消毒副产物前体。这一发现可能会促进国家饮用水供应处理的巨大改进，并降低自来水龙头的消毒副产品浓度。

CBET-1254350Julian FaireyUniversity of ArkansasThere is perhaps no greater challenge faced by drinking water utilities in the United States than meeting disinfection byproduct regulations for trihalomethanes and haloacetic acids. Formation of these regulated chemicals and other potentially toxic disinfection byproducts, such as n-nitrosodimethylamine, is expected to increase as water utilities continue to exploit source waters impacted by algal blooms and wastewater discharges. Fortunately, the burgeoning field of nanotechnology offers promise. Specifically, properties of carbon nanotubes suggest they may have substantial adsorption capacities for disinfection byproducts precursors, which could be further enhanced by manipulating carbon nanotube surface chemistry. The objective of this research project is to reengineer the tunable physicochemical properties of carbon nanotubes for enhanced adsorption of disinfection byproduct precursors. A systematic reductionist approach will be employed to modify physical (e.g., surface area, pore size distribution) and chemical (e.g., surface functional groups, surface charge) properties of carbon nanotubes for enhanced adsorption of trihalomethane, haloacetic acid, and n-nitrosodimethylamine precursors. Equilibrium adsorption capacities of the reengineered carbon nanotubes will be measured in batch isotherm experiments. Kinetic limitations will be assessed using rapid small-scale column tests to determine suitable processes within drinking water treatment plants for carbon nanotube integration. The extent to which direct gasification can regenerate spent carbon nanotubes will be assessed to address cost considerations. Fundamental characterizations of the reengineered carbon nanotubes and disinfection byproduct precursors (e.g., elemental composition by Fourier transform ion cyclotron resonance mass spectroscopy) will facilitate development of structure-property relationships, thus permitting broad applicability of the research findings. The expected outcome of this research is a systematic procedure to fundamentally reengineer carbon nanotubes for enhanced adsorption of disinfection byproduct precursors.A major challenge for many drinking water utilities in the United States is achieving adequate disinfection while limiting formation of disinfection byproducts. As waters become more impaired due to the trickle down impacts of population growth, significant advancements in the removal of disinfection byproduct precursors are critically needed. In this research project, principles of nanotechnology, surface chemistry, and analytical chemistry are leveraged to reengineer carbon nanotubes for effective uptake of disinfection byproduct precursors. This discovery could spur vast improvements in the treatment of the nations drinking water supply and reduce concentrations of disinfection byproducts at the tap.