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。该合作研究由佛罗里达国际大学的Kevin E. O'Shea和Yong Cai教授以及辛辛那提大学的Dionysios D. Dionysiou教授参与。与学生一起，教师们寻求开发一种环保的方法来净化水。高毒性砷和硒对水体的污染是对环境的严重威胁。这影响了全球数亿人的健康。该方法是用天然有机物质（NOM）包裹磁性氧化铁纳米颗粒。包覆的纳米颗粒能强烈结合砷和硒，并能在太阳照射下将它们转化为毒性较小的形式。携带砷和硒的磁性纳米颗粒随后用磁铁从受污染的水中去除。总的来说，这些研究活动预计将加强当地社区、教育机构和研究人员之间的合作。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了使用环保材料的新水处理方法的发展。这些见解的应用可能会加速解决环境问题的相关技术的实施，并推进对天然有机物质和金属相互作用的理解，以确定它们的命运、运输和生物利用度。研究计划强调来自代表性不足群体的人的参与。它还包括一个与当地学校的高中外展项目，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的分子相互作用的基本理解，以及随后的As和Se的NOM光敏氧化还原转化。使用特定的捕获或猝灭剂来研究单个活性氧、电子转移和能量转移过程在NOM光敏转化中的作用。这些基础研究指导选择最有前途的NOM组分，用于接枝到不同尺寸的磁性氧化铁纳米颗粒表面，以进行感兴趣的过程。这项研究预计将有助于制定优化有毒金属的去除和转化的战略。这一过程对水的回用和处理至关重要。

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.