SBIR-STTR Award

Efficient removal and recovery of toxic heavy metals fromindustrial wastewater streams is a major challenge. Industrial wastewatertreatment has been slow in meeting this challenge and still reliesheavily on a conventional technology based upon precipitation/settling,sedimentation, and activated sludge treatment. The toxic heavy metals donot degrade and tend to accumulate in the biological sludge requiringultimate disposal by landfilling as well as the loss of valuable metalresources. This fact makes the removal and recovery of heavy metals fromwastewater potentially economically attractive. In the proposed Phase Ieffort, complexing agents with appropriate solvents will be developed forextracting toxic heavy metals of concern to U.S. E.P.A., especially lead,arsenic, cadmium, chromium and mercury, from dilute wastewaters and thefeasibility of recovering these metals in a uphill facilitated transportmode in microporous hollow fiber membrane contractors will bedemonstrated. Depending upon the complexation chemistry and wastewatercompositions, the proposed approach may be tailored to a specific heavymetal or may be used for simultaneous removal/recovery of multiplemetals. The proposed effort, if successful, will address an urgent needin industrial wastewater treatment and will provide a cost effectivemethod to recover the toxic metals.

Efficient removal and recovery of toxic heavy metals from industrial wastewater streams is a major challenge. The increasing cost of landfilling as well as valuable metal resources make removal and recovery of heavy metals from wastewater potentially economically attractive. During the Phase I effort, the feasibility of recovering toxic metals, such as cadmium, chromium, lead, and mercury, was demonstrated using metal complexing agents with appropriate solvents in an uphill facilitated transport mode in microporous hollow fiber membrane contactors. Depending upon the complexation chemistry and wastewater composition, this approach may be tailored to a specific heavy metal or may be used for simultaneous removal/recovery of multiple metals. During the Phase II efforts, this novel concept will be demonstrated for treating wastewater streams from metal finishing industries with recovery and recycling of the metal values. The proposed approach will first be scaled up by an order of magnitude in bench-scale experiments with simulated wastewater compositions. The novel process will then be demonstrated with a pilot-scale, skid-mounted system at a metal finishing facility. If successful, this recovery system will address an urgent need in industrial wastewater treatment and will provide a cost-effective method to recover the toxic metals.