» ICT II: Decontamination

Remove contaminants from all types of water sources, to get the "drop of poison out of an ocean of water." Co-Leaders: Yi Lu and Charlie Werth

The overarching goal for ICT II is to develop materials, methods, and systems for selective adsorption, catalytic reduction, and oxidation of pollutants that are conventionally difficult to treat such as nitrate, perchlorate and arsenate, metal ions such as lead and mercury, and emerging pollutants such as disinfection by-products. There are two concentration areas in ICT II:

II-A: Design and synthesis of selective sensors and adsorption materials for trace contaminants based on fundamental understanding of water-pollutant-materials interactions across a range of length scales.

II-B: Selective catalytic destruction of difficult-to-treat oxyanions (nitrate and perchlorate) and persistent organic contaminants (halocarbons, antibiotics, NDMA, MTBE).

Efforts in ICT II are aimed at synthesis, characterization, and system integration of new materials for selective removal of very small quantities of persistent and/or emerging contaminants in water based on fundamental understanding of water-pollutant- materials binding and interactions. The core of this effort focuses on selective adsorption, catalytic reduction, and oxidation of pollutants that are not amenable to treatment using conventional methods. These pollutants include conventionally difficult to treat oxyanions such as nitrate, perchlorate and arsenate, metal ions such as lead and mercury, as well as emerging micropollutants like the disinfection by-product NDMA and the antibiotic sulfamethoxazole. Many of the contaminants of concern are present in source waters at trace levels, and in the presence of other constituents at much higher levels (e.g., natural organic matter). Hence, a key focus of ICT II is on selectivity in complex water matrices. The effort also includes activities aimed at developing sensitive and selective biosensors to identify and quantify these compounds in natural waters, as well as the integration of these sensors into multi-step treatment processes. We have a critical mass of researchers with expertise in catalyst and material development, redox transformation of aquatic contaminants, and integration of catalytic materials in water purification systems. Multidisciplinary efforts are being driven foremost by fundamental understanding of water-pollutant-material interactions on catalysts and catalyst supports, and our approach to research will use several unique and complementary strategies and techniques. The team works on the following scientific and technical objectives.

Scientific and Technical Objectives

To understand how nanoscale fluid dynamics and restricted reaction phase space affect the kinetics of adsorption, desorption and ligand binding for catalysts and catalyst support materials constructed within nanoscale pores.
To elucidate reaction pathways and kinetic limitations for catalytic pollutant transformation processes, specifically to selectively remove nitrate, perchlorate, NDMA, MTBE, and sulfamethoxazole to no-action levels in the presence of high background amounts of potable constituents.
To identify the mechanisms responsible for adsorbent and catalyst fouling, assess the reversibility of these processes, and develop regeneration strategies that maximize the life and efficiency of adsorbent and catalyst materials.
To determine the molecular mechanisms needed to sense compounds at the ppt level, specifically to develop parts per trillion sensors for mercury, NDMA, sulfamethoxazole, and perchlorate that are not affected by non-target constituents in water and to develop strategies for engineered systems integrating sensors and catalysts or adsorbents.

Stretch Goal: Parts per trillion (ppt) or lower removal of conventionally difficult to treat and emerging pollutants (e.g., perchlorate, NDMA, MTBE, sulfamethoxazole).

Research Posters

The table below shows the available research posters. To view a poster, simply click on its title below. This requires Adobe Acrobat Reader, which can be downloaded here for free. The Presenting Author column refers to the investigator who presented this poster at the 2005 NSF Site Visit.