This collaborative research program between the University of Massachusetts at Amherst's Polymer Science and Engineering program and The University of Texas at Austin's Chemical Engineering Department focuses on one of the grand challenges of our time, the energy-efficient purification of water for beneficial use in industrial, agricultural, and municipal applications. There are many steps involved in purifying groundwater or contaminated water from operations such as hydraulic fracturing into water suitable for use (or reuse) in oil and gas production operations, as well as agricultural and drinking water applications. However, many of these purification steps begin with removing particles or other contaminants in the water, such as oil droplets in the case of hydraulic fracturing flowback water. When such particulate contaminants are removed from dirty water using membrane filters, the filters become dirty and clogged, leading to reduced performance and increased energy consumption, a problem ubiquitous throughout the membrane filtration industry. This research program builds upon previous encouraging joint research findings between the University of Massachusetts at Amherst and The University of Texas at Austin showing how to modify the surfaces of membranes so that particulate material, such as oil droplets or other particles, are less likely to stick to the membrane surface and subsequently clog the membrane filters. This fundamental research program will explore the basic science that limits the application of current membranes in operations such as municipal wastewater purification and purification of water generated through oil and gas production and exploration activities. The long-range output of this research program would be an enhanced understanding of the fundamental mechanisms that result in contaminants sticking to membranes and clogging them and in understanding novel ways to modify the surfaces of membranes to make them more resistant to particulate contaminants in water. This research could result in membranes with higher performance and longer lifetimes as well as reduced energy consumption to purify many sources of water for a broad range of applications.
Professors Benny Freeman (U Texas Austin) and Todd Emrick (UMass Amherst) propose a collaborative project focusing on fundamental research to prepare, apply, and characterize polymer coatings to ameliorate fouling in water purification membranes. The project seeks to combine synthesis and characterization activities in two primary areas: 1) the development of novel phosphorylcholine (PC)-substituted polyolefins for coating water purification membranes (including microfiltration, ultrafiltration, and reverse osmosis membranes) using polymers carrying a high density of PC groups pendent to the polymer backbone, and 2) the preparation of catechol-containing phosphorylcholine polymers that combine non-fouling zwitterions with surface adhering cross-linkable aromatic derivatives. Both areas share the objective of realizing a dramatic improvement in membrane performance relative to materials in use today, and this objective will be met by collaborative interaction between synthesis in Emrick's group and membrane characterization efforts in Freeman's group. The proposed research responds to the pressing need for advanced fouling-resistant membranes, by producing coated membrane materials that exhibit water flux characteristics in the presence of contaminated water sources (e.g., oily water) that approach flux values of pure water. The collaborative interaction will operate through frequent exchange of students and scheduled teleconference meetings to review progress and plan for productive interactions.
The project responds to the critical scientific and technological challenges associated with water purification, recognizing that the combination of population growth and increasing strain on fresh water supplies represents a serious societal threat in the United States and worldwide. Accelerating discoveries that improve water purification membranes can be accomplished most effectively through collaborative research that enables rapid and effective testing of novel polymer materials prepared specifically for membrane coating and fouling prevention. Membranes with greater fouling resistance would use less energy to purify, for example, hydraulic fracturing flowback water, produced water and other impaired water sources.
Broader impact efforts are intended to benefit both the research and broader scientific communities, with areas of emphasis including: 1) leadership and organization in conferences and symposia dedicated to polymer membranes and water purification; 2) providing research and educational opportunities for minority and physically challenged individuals; and 3) pursuing technology transfer strategies that facilitate the transition of laboratory discoveries to products and processes that contribute to American competitiveness.
