Collaborative Research: Adsorption and Photochemical Transformations of Arsenic and Selenium Species by Natural Organic Matter-Coated Magnetic Nano-sized Iron Oxide Particles

该奖项由化学部门的环境化学科学项目和化学、生物工程、环境和运输系统部门的环境工程项目共同支持。这项合作研究涉及佛罗里达国际大学的Kevin E.O‘Shea教授和Yong Cai教授，以及辛辛那提大学的Dionsios D.Dionisiou教授。教职员工和他们的学生一起，寻求开发一种环保的净化水方法。高毒性砷(As)和硒(Se)对水体的污染对环境构成严重威胁。这影响了全球数亿人的健康。方法是用天然有机物(NOM)包覆磁性氧化铁纳米颗粒。包覆的纳米颗粒可以强烈地结合砷和硒，并在太阳辐射下将它们转化为毒性较低的形式。携带砷和硒的磁性纳米颗粒后来被磁铁从受污染的水中移除。总体而言，预计研究活动将加强当地社区、教育机构和调查人员之间的合作。这项研究的更广泛的社会影响包括促进可持续发展。从这些研究中获得的知识指导使用环境友好型材料开发新的水处理方法。应用这些见解可能会加速实施解决环境问题的相关技术，并促进对天然有机物和金属相互作用的了解，以确定它们的去向、运输和生物可利用性。研究计划强调任职人数不足的群体的参与。它还包括与当地学校的一个高中外展项目，以教育学生关于水质和水污染问题。该项目旨在发展对As和Se物种与分级NOM的分子相互作用的基本了解，以及随后NOM光敏的As和Se的氧化还原转化。使用特定的捕捉剂或猝灭剂来研究各个活性氧物种、电子转移和能量转移过程在NOM光敏转化中的作用。这些基础研究指导了最有希望的NOM组分的选择，用于接枝到不同尺寸的磁性氧化铁纳米颗粒的表面上，用于感兴趣的过程。预计这项研究将有助于制定优化有毒金属去除和转化的战略。这样的工艺对水的再利用和处理至关重要。

This award is supported jointly by the Chemistry Division's Environmental Chemical Sciences Program and the Environmental Engineering Program in the Division of Chemical, Bioengineering, Environmental, and Transport Systems. The collaborative study involves Professors Kevin E. O'Shea and Yong Cai from Florida International University and Professor Dionysios D. Dionysiou from University of Cincinnati. Together with their students, the faculty members seek to develop an environmentally-friendly approach to purifying water. Water contamination by highly toxic arsenic (As) and selenium (Se) is a serious threat to the environment. This has affected the health of hundreds of millions of humans globally. The approach is to coat magnetic iron oxide nanoparticles with natural organic matter (NOM). The coated nanoparticles can strongly bind arsenic and selenium and can convert them to less toxic forms upon solar irradiation. The magnetic nanoparticles carrying the arsenic and selenium are later removed from the contaminated water with a magnet. Overall, the research activities are expected to strengthen co-operation among the local community, educational institutes, and investigators. Thebroader societal impacts of this research include enhancing sustainable development. The knowledge obtained from these studies guides the development of new water treatment methodologies using environmentally-friendly materials. Application of these insights may accelerate the implementation of related technologies in addressing environmental problems, as well as advance the understanding of the interaction of natural organic matter and metals to determine their fate, transport and bioavailability. The research plan emphasizes participation of persons from underrepresented groups. It also includes a high school outreach program with local schools to educate the students on water quality and water contamination issues.The project seeks to develop a fundamental understanding of the molecular interactions of As and Se species with fractionated NOM and the subsequent NOM-photosensitized redox transformations of As and Se. Specific trapping or quenching agents are used to study the roles of individual reactive oxygen species, electron transfer and energy transfer processes in the NOM photosensitized transformations. These fundamental studies guide the selection of the most promising NOM fractions for grafting onto the surface of different sized magnetic iron oxide nanoparticles for the process of interest. The research is expected to aid in the development of strategies for optimizing removal and conversion of toxic metals. Such a process is is critical to water reuse and treatment.