Transport of Solutes and Macromolecules through Reverse Osmosis and Nanofiltration Membranes

通过反渗透和纳滤膜传输溶质和大分子

• 批准号: 0332217
• 负责人: Benito Marinas
• 金额: --
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2010-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0332217&HistoricalAwards=false
• 关键词: Transport; Solutes; Macromolecules; through; Reverse

0332217 Marinas The primary objective of this research is to elucidate the mechanisms by which water contaminants, ranging from small neutral molecules to large macromolecules, permeate through reverse osmosis and nanofiltration membranes. Selected solutes and macromolecules are arsenious acid, atrazine (216 Daltons), Rhodamine WT (480 Daltons), and three coliphages (fr, MS2, T4) ranging in size from 19 to 80 nm. This list resulted from a compromise among several criteria including the selection of water contaminants of current interest and surrogates used to assess the performance of RO/NF membranes, small solutes and macromolecules known to be poorly-rejected by some by RO/NF membranes, and compounds quantifiable in multi-solute samples with relatively simple interference-free analytical techniques. The scope of work of the project is designed to develop a fundamental understanding for the mechanisms responsible for the permeation of water and various types of solutes through RO and NF membranes including elucidating the role of the concentration polarization phenomenon in the overall transport of target solutes and macromolecules. In order to accomplish this goal, permeation experiments will be performed to characterize the contribution to overall solute/macromolecule permeation by sorption/diffusion/desorption through the membrane polymer matrix and advection through membrane nanopores, as well as the effect of concentration polarization on both types of permeation. Experimental variables under consideration include hydraulic pressure, background and target solute concentration, temperature, and pH. Then, the size distribution of nanopores in the active layers of RO and NF membranes will be characterized by a combination of atomic force and scanning electron microscopy, and gas adsorption/desorption techniques. It is anticipated that characterizing the pore size distribution of RO/NF membranes will require integrating the results obtained with these three methods. The final task of the study will be the development of a mechanistic model to represent the permeation of water, solutes and macromolecules through RO and NF membranes.

本研究的主要目的是阐明水污染物，从小的中性分子到大的大分子，通过反渗透和纳滤膜渗透的机制。所选溶质和大分子为亚砷酸、阿特拉津（216道尔顿）、罗丹明WT（480道尔顿）和三种噬菌体（fr、MS2、T4），尺寸从19 nm到80 nm不等。这份清单是在几个标准之间的折衷结果，包括选择当前感兴趣的水污染物和用于评估RO/NF膜性能的替代品，已知一些RO/NF膜很难拒绝的小溶质和大分子，以及使用相对简单的无干扰分析技术在多溶质样品中可量化的化合物。该项目的工作范围旨在对水和各种类型的溶质通过反渗透膜和纳滤膜的渗透机制有一个基本的了解，包括阐明浓度极化现象在目标溶质和大分子的整体运输中的作用。为了实现这一目标，将进行渗透实验，以表征膜聚合物基质的吸附/扩散/解吸和膜纳米孔的平流对溶质/大分子整体渗透的贡献，以及浓度极化对这两种渗透的影响。考虑的实验变量包括液压、背景和目标溶质浓度、温度和ph。然后，通过原子力和扫描电子显微镜以及气体吸附/解吸技术的组合来表征RO和NF膜活性层中纳米孔的尺寸分布。预计表征RO/NF膜的孔径分布将需要整合这三种方法获得的结果。研究的最后一项任务将是建立一个机制模型来表示水、溶质和大分子通过反渗透膜和滤膜的渗透。