RUI Ramifications of Ethanol Usage as a Biofuel: Quantifying Sources and Impacts on the Light Absorbing Properties of Rainwater

RUI 使用乙醇作为生物燃料的影响：量化雨水的来源及其对光吸收特性的影响

• 批准号: 1440425
• 负责人: Robert Kieber
• 金额: $ 31.39万
• 依托单位: University of North Carolina at Wilmington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-03-01 至 2019-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1440425&HistoricalAwards=false
• 关键词: RUI; Ramifications; Ethanol; Usage; Biofuel

This project seeks to investigate the atmospheric chemistry of ethanol and the impacts of increasing levels ethanol production centered on its use as a gasoline fuel additive. Colored dissolved organic matter (CDOM) is another potential environmental source having impact on the concentration of ethanol in rainwater. Preliminary data suggests that ethanol can be produced by photolysis of rainwater after short (~4 hour) exposure to simulated sunlight. These RUI (Research at Undergraduate Institution) PIs have previously shown that there is a measurable concentration difference of ethanol in precipitation samples collected in sites from Wilmington NC and in Sao Paulo Brazil. The concentrations of ethanol in rainwater vary significantly between rain events, with higher concentrations occurring during storms associated with continental air masses. High concentrations of ethanol in precipitation are said to influence the oxidizing capacity of the atmosphere and may have indirect effects on solar radiative transfer and climate.The project seeks to answer three related questions: 1)What are the relative proportions of biofuel and naturally derived ethanol in ambient rainwater? 2)What are the impacts of photolysed ethanol on the chromophoric properties of rainwater? 3) What are the reaction pathways and molecular level compositional changes responsible for changes in CDOM abundance and photochemical lability upon ethanol production?

该项目旨在研究乙醇的大气化学和乙醇生产水平的提高对汽油燃料添加剂的影响。 有色溶解有机物（CDOM）是影响雨水中乙醇浓度的另一个潜在环境源。初步数据表明，在短时间（约4小时）暴露于模拟阳光后，雨水可通过光解产生乙醇。这些RUI（本科院校研究）PI先前已表明，在北卡罗来纳州威尔明顿和巴西圣保罗的研究中心收集的降水样品中，乙醇存在可测量的浓度差异。雨水中乙醇的浓度在降雨事件之间变化很大，在与大陆气团相关的风暴期间浓度较高。降水中高浓度的乙醇据说会影响大气的氧化能力，并可能对太阳辐射传输和气候产生间接影响。该项目试图回答三个相关问题：1）环境雨水中生物燃料和自然产生的乙醇的相对比例是多少？2)光解乙醇对雨水的发色特性有什么影响？3)乙醇生产过程中CDOM丰度和光化学不稳定性变化的反应途径和分子水平的组成变化是什么？