Using the RO/ED Method to Isolate Low-Ash Dissolved Organic Matter in High Yield along a Salinity Gradient

使用 RO/ED 方法沿盐度梯度高产分离低灰分溶解有机物

• 批准号: 1061188
• 负责人: E. Michael Perdue
• 金额: --
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-01 至 2012-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1061188&HistoricalAwards=false
• 关键词: Using; RO; ED; Method; Isolate

The chemical characteristics of dissolved organic matter (DOM) are expected to be modified by an array of biogeochemical processes (sources, sinks, transformations) along a salinity gradient such as the river-estuary-ocean system. To quantify such changes in the quality and quantity of DOM, scientists have relied upon methods of isolation such as solid-phase extractions (SPE) and ultrafiltration (UF), for which yields of DOM typically decline substantially along the salinity gradient. Observed changes in the chemistry of isolated samples of DOM along a salinity gradient are the integrated result of biogeochemical processing and salinity-dependent fractionation of DOM as the retention characteristics of individual compounds are modified by increased salinity. Most prior work has interpreted measured compositional changes solely in terms of biogeochemistry. In this project, researchers at the Georgia Institute of Technology will conduct laboratory experiments to optimize a coupled reverse osmosis/electrodialysis (RO/ED) method to maximize the yield of DOM and minimize co-concentration of inorganic solutes. Field experiments along the full salinity gradients of the Satilla and Altamaha rivers in southeast Georgia will provide feedback to the design and optimization of the modified RO/ED method. High-quality, low-ash samples of DOM will be collected across a range of salinities and characterized chemically and spectroscopically (elemental analyses (CHONS), acid-base titrations, 13C NMR and FTICR spectrometry). The goals of the proposed research are: (1) to extend the range of water chemistries over which the RO/ED method can be applied, (2) to develop new capabilities for removing residual inorganic materials to obtain low-ash samples of marine DOM, and (3) to isolate DOM in high yield along several complete river-estuary-ocean salinity gradients and to test the hypothesis that DOM is not significantly fractionated by the RO/ED isolation method.. Broader Impacts: The project will provide financial support for the doctoral research of one graduate student. Knowledge gained during the project will be shared formally through publications in the peer-reviewed literature and presentations at national and international meetings and directly with current collaborators and other scientists who have requested the PI?s formal support in using the RO/ED method to isolate DOM from a variety of natural waters.

溶解有机物（DOM）的化学特性将受到一系列沿着盐度梯度变化的海洋地球化学过程（源、汇、转化）的影响，如河流-河口-海洋系统。为了量化DOM的质量和数量的变化，科学家们依赖于分离方法，如固相萃取（SPE）和超滤（UF），DOM的产量通常沿着盐度梯度大幅下降。观察到的化学变化的DOM隔离样品沿着的盐度梯度的综合结果的土壤地球化学处理和盐度依赖分馏的DOM的保留特性的个别化合物被修改的盐度增加。大多数先前的工作已经解释了测量的成分变化，仅在地球化学方面。在该项目中，格鲁吉亚理工学院的研究人员将进行实验室实验，以优化耦合反渗透/电渗析（RO/艾德）方法，以最大限度地提高DOM的产量，并最大限度地减少无机溶质的共浓缩。沿着格鲁吉亚东南部的Satilla河和Altamaha河的全盐度梯度的现场实验将为改进的RO/艾德方法的设计和优化提供反馈。将在各种盐度范围内收集高质量、低灰分的DOM样品，并进行化学和光谱表征（元素分析（CHONS）、酸碱滴定、13 C NMR和FTICR光谱）。拟议研究的目标是：（1）扩大RO/艾德法可应用的水化学范围，（2）开发新的能力，以去除残留的无机物质，获得海洋DOM的低灰分样品，沿着几条完整的河流-河口-海洋盐度梯度和测试的假设，DOM是没有显着分馏的RO/艾德隔离方法。更广泛的影响：该项目将为一名研究生的博士研究提供财政支持。在项目期间获得的知识将通过同行评审文献中的出版物和国家和国际会议上的演示文稿正式共享，并直接与当前合作者和要求PI的其他科学家共享。的正式支持使用RO/艾德方法从各种自然沃茨中分离DOM。