High-Performance Extraction of Heavy Metals with Tethered Metal-Binding Ligands

EPA Contract Number: 68D98151
Title: High-Performance Extraction of Heavy Metals with Tethered Metal-Binding Ligands
Investigators: Hammen, Richard F.
Small Business: ChelaTech Inc.
EPA Contact: Manager, SBIR Program
Phase: I
Project Period: September 1, 1998 through March 1, 1999
Project Amount: $70,000
RFA: Small Business Innovation Research (SBIR) - Phase I (1998) RFA Text |  Recipients Lists
Research Category: Hazardous Waste/Remediation , SBIR - Waste , Small Business Innovation Research (SBIR)


The removal of metals from contaminated water is critical to many manufacturing industries. Both internal requirements and external environmental regulations place an economic premium on producing high-purity water that is free of detectable metal ion contamination (zero discharge). Conventional ion exchange technologies used today can only achieve zero discharge with exponentially increasing costs, due to the limitations of the kinetics of diffusion of metals to the surface of ion exchange resins. To avoid boundary layer diffusion limitation, ChelaTech has developed a technology of covalently attaching a variety of tether molecules to porous silica gel. The tether length can be controlled and is made to be 15-400 Angstroms long. The tether is then covalently coupled to an appropriate ligand or metal-binding reagent. By "dangling" the reagent away from the solid surface, the reagent interacts with solute molecules pumped through the porous bed with unprecedented reaction and adsorption kinetics. This project will prepare High-Performance Extraction media with high-affinity metal binding agents that are selective for extracting mercury, cadmium, hexavalent chrome, and arsenate ions from contaminated water. The media will be tested for their efficacy and economics of performance.

Supplemental Keywords:

small business, SBIR, remediation, heavy metals, wastewater, engineering, chemistry, EPA., Economic, Social, & Behavioral Science Research Program, Scientific Discipline, Toxics, Waste, Water, hexavalent chromium, National Recommended Water Quality, Physics, Remediation, Wastewater, Chemistry, Engineering, Hazardous, 33/50, Engineering, Chemistry, & Physics, Market mechanisms, Mercury, wastewater treatment, cadmium & cadmium compounds, wastewater remediation, metal ion removal, metal binding, metal recovery, pollution control, carbon dioxide, mercury & mercury compounds, emission reductions, cost effective, cadmium, extraction of metals, heavy metal contamination, control technologies, heavy metals, waste water treatment, ion exchange, metal ligand

Progress and Final Reports:

  • Final Report