CAREER: Establishing a New Retrosynthetic Framework for Identifying Precursors of Priority Disinfection Byproducts in Recycled Wastewater

职业：建立新的逆合成框架来识别回收废水中优先消毒副产品的前体

• 批准号: 1944810
• 负责人: Daniel McCurry
• 金额: $ 53.28万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-15 至 2025-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1944810&HistoricalAwards=false
• 关键词: CAREER; Establishing; New; Retrosynthetic; Framework

Water scarcity is a serious and growing problem for the Nation and the world. One approach to help solve the issue of water scarcity is to recycle treated wastewater. Re-used wastewater needs to be treated to a sufficient quality to make it fit for use, including for irrigation, industry, and even drinking water. The most important step in the water recycling process is disinfection to kill viruses and bacteria. Disinfection is usually done by adding chemical oxidants like chlorine (bleach). The problem with using these oxidants is that they can react with organic molecules naturally present in the water to form byproduct chemicals. Many of these byproducts are highly toxic and potentially carcinogenic and must be removed. The goal of this CAREER research project is to understand the chemical reactions leading to toxic byproduct formation during water recycling. This knowledge will allow control or the elimination of byproduct formation without compromising disinfection. Successful completion of this research will help the Nation develop feasible approaches to address water scarcity, while protecting the public. Results will be used to inform and educate the public on engineering and water issues through outreach efforts in collaboration with Engineers Without Borders and with a local high school in Los Angeles.The goal of this CAREER project is to develop a new framework for identifying the precursors and formation pathways of carcinogenic disinfection byproduct (DBP) chemicals in recycled wastewater. This goal will be achieved through specific research focused on three classes of DBPs that are known to convey the highest degree of risk. DBPs remain a serious obstacle to wider adoption of water reuse, as they are the chemicals in recycled wastewater of greatest human health concern; even greater than pharmaceuticals or industrial contaminants. Minimizing their formation requires identifying their precursors and formation pathways so that treatment systems can be re-engineered to prevent formation. In the first step, a hypothesis will be generated about the functional groups likely to lead to formation of DBPs using retrosynthesis, a technique developed by synthetic chemists to select chemical precursors for synthetic targets. Next, a bottom-up approach will be used to demonstrate that the predicted precursor functional groups are responsible for observed formation. Precursors will be modified to less reactive derivatives and DBP formation potential will be compared to controls. Derivatized precursors will then be analyzed to identity specific precursor molecules. Finally, a top-down approach will be employed to develop the final precursor candidate list. These analytes will be measured in recycled wastewater and their share of the precursor pool will be quantified by both formation potential and simulated distribution system testing for validation. The education and outreach component of this CAREER project is composed of three complementary activities. The PI will work with the USC Engineers Without Borders (EWB) group on water treatment projects in Latin America, applying tools and knowledge from the research component to a disinfection system built by undergraduates. The PI will also host a high school student and teacher in the lab and involve the teacher’s class in the EWB project by remotely transmitting raw data for analysis. Finally, the PI will develop a new problem-based “Tradeoffs in Disinfection” module for the sophomore-level environmental engineering course, using the system built by the USC EWB team in Guatemala as a case study.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.

水资源短缺是美国和世界面临的一个日益严重的问题。帮助解决水资源短缺问题的一种方法是回收处理过的废水。重复使用的废水需要经过足够的处理，以使其适合使用，包括灌溉，工业，甚至饮用水。水循环过程中最重要的一步是消毒，以杀死病毒和细菌。消毒通常是通过添加化学氧化剂如氯（漂白剂）来完成的。使用这些氧化剂的问题是，它们会与水中天然存在的有机分子发生反应，形成副产品化学物质。这些副产品中有许多具有剧毒和潜在致癌性，必须清除。这个CAREER研究项目的目标是了解水循环过程中导致有毒副产物形成的化学反应。这一知识将允许在不影响消毒的情况下控制或消除副产品的形成。这项研究的成功完成将有助于国家制定可行的方法来解决水资源短缺问题，同时保护公众。研究结果将通过与无国界工程师组织和洛杉矶一所当地高中的合作，向公众宣传和教育工程和水问题。本CAREER项目的目标是开发一个新的框架，以确定再生废水中致癌消毒副产物（DBP）化学物质的前体和形成途径。这一目标将通过对已知具有最高风险程度的三类dbp进行具体研究来实现。dbp仍然是广泛采用水回用的一个严重障碍，因为它们是循环废水中对人类健康最关切的化学品；甚至比药品或工业污染物还要严重。为了最大限度地减少它们的形成，需要识别它们的前体和形成途径，以便重新设计处理系统以防止地层形成。在第一步中，将使用反合成技术对可能导致dbp形成的官能团进行假设，这是合成化学家开发的一种技术，用于为合成目标选择化学前体。接下来，将使用自下而上的方法来证明预测的前体官能团负责观察到的形成。前体将被修饰成反应性较低的衍生物，DBP的形成势将与对照物进行比较。然后分析衍生前体以识别特定的前体分子。最后，将采用自上而下的方法来制定最终的前体候选名单。这些分析物将在回收废水中进行测量，它们在前体池中的份额将通过形成潜力和模拟分配系统测试进行量化，以进行验证。这一职业发展项目的教育和外联部分由三个相互补充的活动组成。PI将与南加州大学无国界工程师组织（EWB）在拉丁美洲的水处理项目上合作，将研究部分的工具和知识应用于本科生建立的消毒系统。PI还将在实验室接待一名高中学生和一名教师，并通过远程传输原始数据进行分析，让教师所在的班级参与EWB项目。最后，PI将使用USC EWB团队在危地马拉建立的系统作为案例研究，为大二的环境工程课程开发一个新的基于问题的“消毒权衡”模块。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Intermural Online Research Group Meetings As Professional Development Tools for Undergraduate, Graduate, and Postdoctoral Trainees

校间在线研究小组会议作为本科生、研究生和博士后学员的专业发展工具

• DOI: 10.1089/ees.2021.0147
• 发表时间: 2022
• 期刊: Environmental Engineering Science
• 影响因子: 1.8
• 作者: Kim, Euna;Driessen, Olivia M.;McCurry, Daniel L.;Sivey, John D.
• 通讯作者: Sivey, John D.

Formation and Fate of Nitromethane in Ozone-Based Water Reuse Processes

臭氧水回用过程中硝基甲烷的形成和去向

• DOI: 10.1021/acs.est.0c07895
• 发表时间: 2021
• 期刊: Environmental Science & Technology
• 影响因子: 11.4
• 作者: Shi, Jiaming Lily;Plata, Sophia L.;Kleimans, Marco;Childress, Amy E.;McCurry, Daniel L.
• 通讯作者: McCurry, Daniel L.