Non-target analysis of radicals in sonochemical and advanced oxidation processes (AOPs)

声化学和高级氧化过程 (AOP) 中自由基的非目标分析

• 批准号: RTI-2022-00340
• 负责人: Boffito, DariaCamilla
• 金额: $ 7.54万
• 依托单位: École Polytechnique de Montréal
• 依托单位国家: 加拿大
• 项目类别: Research Tools and Instruments
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=743057
• 关键词: Non; target; analysis; radicals; sonochemical

Several chemical and biological processes involve short-lived radicals that are either generated by a reaction or the interaction of a source of energy with the matter. To date, most mechanisms of the radical formation and their fate are still elusive to understand due to their short lifetime. This is the case for several research projects in the teams of Prof. Boffito and Yargeau, which involve radicals generated either sonochemically or by advanced oxidation redox processes (AOPs). In sonochemical processes, the energy transmitted by ultrasound (20 kHz - 1 MHz) produces acoustic cavitation, i.e. the formation, growth, and collapse of rarefied gas micro-bubbles. Their collapse results in micro hot spots (up to 5000 K and 1000 atm), and high speed jets (100 m s-1). In these conditions, radicals form. Their type and concentration depends on several factors, such as the characteristics of the ultrasound equipment and the physico-chemical identity of the reaction medium. The radicals thus generated can be leveraged to intensify several chemical and physical processes, including AOPs. AOPs describe a broad family of oxidation processes to unselectively degrade organic pollutants by radicals generated in different ways. These include ozonation, plasma, electrochemical oxidation, chemical oxidation, photocatalysis, sonochemistry, and combined AOPs. We request a portable electron spin resonance (ESR) spectrophotometer for the detection of free radicals. ESR is key to identify and quantify the radicals involved in sonochemical processes not only to establish the mechanisms of sonochemistry, which are still largely ignored, but also to design efficient sonochemical reactors to maximize yield and selectivity while minimizing energy requirements. Similarly, quantifying reactive oxidation species and intermediates in AOPs is crucial to design more efficient AOP systems and to identify the degradation mechanisms of contaminants of emerging concern (CECs). This allows to design methods to completely mineralize pollutants leading to no residual ecotoxicity. There are no portable ESR apparatuses in Canada. Non-portable ESR are available in 5 Canadian institutions but require re-locating reactors. We anticipate that many different research groups will request access to the ESR both from academia and industry. ESR finds application to investigate the activity of enzymes, and tissue damage by free radicals, in geological studies for absolute dating and in industrial applications for quality control of product stability and shelf-life. It will also help developing new collaboration with both academic and industrial partners. The acquisition will greatly enhance the quality of the research of at least 20 HQP and provide them with marketable skills to work not only in scientific research but also in commercial sectors such as pharmaceuticals and personal care sectors, water remediation, plastics, fibers, and food products.

一些化学和生物过程涉及短暂的自由基，这些自由基是由能量源与物质的反应或相互作用产生的。到目前为止，自由基的形成和它们的命运的大多数机制仍然是难以捉摸的理解，由于它们的寿命短。Boffito和Yargeau教授团队的几个研究项目就是这种情况，这些项目涉及声化学或高级氧化还原过程（AOP）产生的自由基。在声化学过程中，由超声（20 kHz - 1 MHz）传输的能量产生声空化，即稀薄气体微泡的形成、生长和破裂。它们的崩溃导致微热点（高达5000 K和1000 atm）和高速射流（100 m s-1）。在这些条件下，自由基形成。它们的类型和浓度取决于几个因素，如超声设备的特性和反应介质的物理化学特性。由此产生的自由基可以用来强化几个化学和物理过程，包括AOP。高级氧化法描述了一个广泛的家庭的氧化过程，非选择性地降解有机污染物的自由基产生的不同方式。这些方法包括臭氧化、等离子体、电化学氧化、化学氧化、超声波化学、声化学和组合的高级氧化工艺。我们要求一个便携式电子自旋共振（ESR）分光光度计检测自由基。ESR是识别和量化声化学过程中所涉及的自由基的关键，不仅可以建立声化学机制，这在很大程度上仍然被忽视，而且可以设计高效的声化学反应器，以最大限度地提高产率和选择性，同时最大限度地减少能源需求。同样，定量反应性氧化物种和中间体的AOP是至关重要的设计更有效的AOP系统，并确定新出现的关注污染物（CEC）的降解机制。这使得设计方法完全矿化污染物，导致没有残留的生态毒性。加拿大没有便携式ESR仪器。加拿大有5个机构提供非便携式ESR，但需要重新安置反应堆。我们预计，许多不同的研究小组将要求从学术界和工业界获得ESR。ESR可用于研究酶的活性和自由基对组织的损伤，在地质研究中用于绝对测年，在工业应用中用于产品稳定性和保质期的质量控制。它还将有助于与学术和工业合作伙伴开展新的合作。此次收购将大大提高至少20名HQP的研究质量，并为他们提供市场化的技能，不仅可以在科学研究领域工作，还可以在制药和个人护理行业，水修复，塑料，纤维和食品等商业领域工作。