Mechanistic Studies of Water Disinfectants on Iron Interfaces

水消毒剂对铁界面的作用机理研究

• 批准号: 2108316
• 负责人: Kathryn Perrine
• 金额: $ 25.85万
• 依托单位: Michigan Technological University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2108316&HistoricalAwards=false
• 关键词: Mechanistic; Studies; Water; Disinfectants; Iron

With support from the Environmental Chemical Sciences Program in the Division of Chemistry, Kathryn Perrine and her students will study fundamental chemical interactions between chloramine, a compound used for water disinfection, with iron, iron oxide, and iron carbonate surfaces. Disinfectants are used to treat pathogens in distribution water lines, but also react with natural organic matter to produce undesired byproducts that can make their way into ground water. (Mono)chloramine is a preferred oxidizing disinfectant since it produces fewer byproducts than other chlorine-containing disinfectants. Iron, iron oxide, and iron carbonate surfaces are ubiquitous in the environment and present as minerals and iron-containing distribution lines. The surface adsorption mechanism and deactivation of chloramine on iron interfaces is not well understood. This project will investigate the surface chemical reaction and decomposition mechanisms of chloramine on well-defined interfaces. These studies have the potential to advance our understanding of oxidation mechanisms in complex mixtures in aqueous systems that impact the effect of contaminants in water quality. Undergraduate students will experience summer research internships and precollege outreach activities. Students in grades 6-12 will participate in inquiry-based labs that will be developed as part of Michigan Tech’s summer youth programs. These activities will focus on aqueous surface chemistry and corrosion, effects of pH on metal dissolution, and surface reactions at the liquid/solid interface.The key objectives will be addressed on the kinetic adsorption and decomposition mechanism of chloramine on iron interfaces at the gas/solid interface on well-defined single crystal surfaces. The influence of the iron surface sites and hydroxyl sites from water and H2 dissociation will promote or block the chloramine reaction and decomposition pathways. The adsorption of chloramine on iron at the liquid/solid interface will be measured using the PI’s new in situ polarized modulated infrared reflection absorption spectroscopy (PM-IRRAS) method at the air/liquid/solid interface to connect the surface mechanism under pristine conditions with realistic reactions in the condensed phase. Using novel surface analysis techniques that measure reactions at the gas/solid and liquid/solid interface, the research being conducted under this award, has the potential to impact areas across disciplines focusing on water resources and their purification, with societal implications associated with water sourcing, maintenance and management.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在化学系环境化学科学项目的支持下，Kathryn Perrine和她的学生将研究氯胺（一种用于水消毒的化合物）与铁、氧化铁和碳酸铁表面之间的基本化学相互作用。消毒剂用于处理配水管线中的病原体，但也与天然有机物反应，产生不需要的副产品，这些副产品可以进入地下水。（单）氯胺是优选的氧化消毒剂，因为它比其它含氯消毒剂产生更少的副产物。铁、氧化铁和碳酸铁表面在环境中普遍存在，并以矿物质和含铁分布线的形式存在。氯胺在铁表面的吸附机理和失活机理目前还不清楚。本计画将探讨氯胺在明确界面上的表面化学反应与分解机制。这些研究有可能促进我们对水系统中复杂混合物的氧化机制的理解，从而影响污染物对水质的影响。本科生将体验暑期研究实习和大学预科外展活动。6-12年级的学生将参加基于探究的实验室，这些实验室将作为密歇根理工大学夏季青年项目的一部分开发。这些活动将集中在水的表面化学和腐蚀，pH值对金属溶解的影响，以及在液体/固体界面的表面反应。主要目标将是在明确的单晶表面上的气/固界面上的铁界面上的氯胺的动力学吸附和分解机理。水和H2解离的铁表面位和羟基位的影响将促进或阻断氯胺反应和分解途径。氯胺在铁上的吸附在液/固界面将使用PI的新的原位偏振调制红外反射吸收光谱（PM-IRRAS）方法在空气/液/固界面连接在原始条件下的表面机制与现实的反应在凝聚相测量。使用新型表面分析技术，测量气/固和液/固界面的反应，在此奖项下进行的研究，有可能影响跨学科领域，重点是水资源及其净化，与水资源相关的社会影响，该奖项反映了NSF的法定使命，并通过使用基金会的学术价值和更广泛的影响审查标准。