Science Inventory

LINEAR POLYMER CHAIN AND BIOENGINEERED CHELATORS FOR METALS REMEDIATION

Impact/Purpose:

Metals are a recirculating problem in the environment since they cannot be degraded or decomposed like many organic contaminants. Consequently, remediation should involve not only extraction but also recovery. This proposal deals with a novel approach using immobilized linear polymer chains which permit extremely strong metal binding and easy, on-demand release using a simple change in the eluting solution pH.

These linear polymers provide strong binding to the metal of interest, which is likely a result of them "wrapping around ,the metal" to attain a free energy minimum. The linear polymers can also be "unwrapped" by altering the intramolecular interactions (e.g.. H-binding, electrostatic attractions) using simple pH adjustments, thereby providing easy, quantitative metal recovery. By selecting the side chain functionality, metal selectivity can be enhanced. The availability of various side chain functionalities has proven this technology successful for binding oxyanions (e.g. chromates, arsenates, etc.). The immobilization of the chelators makes the exchanger reusable, and while the biopolymers tested thus far have been subjected to harsh chemical environments there is no noticeable degradation. The extended lifetime of this system would result in lower long-term operating costs.

This proposal outlines the use of (i) short chain linear biopolymers, (ii) combinatorial chemistry and micro x-ray fluorescence in determination of a successful copolymer, and (iii) short chain mixed residue biopolymers which are produced using genetic engineering. These biopolymer systems are evaluated through breakthrough curves, which are generated through the use of a flow injection analysis system coupled to a flame atomic absorption spectrophotometer. The genetic engineering approach has unique long-term implications with the possible enhancement of

Metals are a recirculating problem in the environment since they cannot be degraded or decomposed like many organic contaminants. Consequently, remediation should involve not only extraction but also recovery. This proposal deals with a novel approach using immobilized linear polymer chains which permit extremely strong metal binding and easy, on-demand release using a simple change in the eluting solution pH.

These linear polymers provide strong binding to the metal of interest, which is likely a result of them "wrapping around ,the metal" to attain a free energy minimum. The linear polymers can also be "unwrapped" by altering the intramolecular interactions (e.g.. H-binding, electrostatic attractions) using simple pH adjustments, thereby providing easy, quantitative metal recovery. By selecting the side chain functionality, metal selectivity can be enhanced. The availability of various side chain functionalities has proven this technology successful for binding oxyanions (e.g. chromates, arsenates, etc.). The immobilization of the chelators makes the exchanger reusable, and while the biopolymers tested thus far have been subjected to harsh chemical environments there is no noticeable degradation. The extended lifetime of this system would result in lower long-term operating costs.

This proposal outlines the use of (i) short chain linear biopolymers, (ii) combinatorial chemistry and micro x-ray fluorescence in determination of a successful copolymer, and (iii) short chain mixed residue biopolymers which are produced using genetic engineering. These biopolymer systems are evaluated through breakthrough curves, which are generated through the use of a flow injection analysis system coupled to a flame atomic absorption spectrophotometer. The genetic engineering approach has unique long-term implications with the possible enhancement of

Description:

The 3-year GCHSRC grant of $150,000 levers financial assistance from the University ($94,500 match) as well as collaborative assistance from LANL and TCEQ in the project. Similarly, a related project supported by the Welch Foundation will likely contribute to the knowledge base that will advance this particular project. Major equipment supplied by either the University or outside funding agencies will also be used in the context of this project at no cost to GCHSRC. The novel science and technology used to attack a problem that has been on the table for decades, should produce noteworthy and publishable results throughout the duration of the project's three year funding period. While the timeline and tasks laid out in the proposal are goals that will be diligently targeted, the pioneering science rather that the application of technology may advance or retard progress beyond that noted. Obviously, we optimistically desire an accelerated timetable for our successes. Regardless, a diverse talent pool combine with major equipment and financial assets from several sources are dedicated to tackling a challenging and ongoing problem in metal remediation and reclamation.

URLs/Downloads:

URL

2004 Progress Report

Record Details:

Record Type: PROJECT (ABSTRACT)
Start Date: 12/01/2003
Completion Date: 11/30/2004
Record ID: 79874