Bio-inspired Lixiviants for Selective Extraction of Valuable Metals from Municipal Solid Waste Incinerator Ash

Metals such as rare earths, copper, cobalt, and nickel continue to be critical to the energy industry and advanced technology applications. Traditional mining of these elements is predominantly located in far-flung regions of the world. MSWI ashes represent a unique opportunity as a source for some of these metals here in the U.S. The current unit cost of metal extraction and refinement, particularly from waste minerals, is too high from environmental, capital-equipment, and reagent bases. Reducing each of these limitations and refining mineral waste such as MSWI ash will have a tremendous impact on metals’ domestic production. A technical solution to these problems will increase the domestic supply of metals, reduce foreign reliance for supply, reduce consumer cost of downstream power and new technology devices, and increase the overall competitiveness of the U.S. We propose to use bio-inspired molecules, complemented by conventional chemical reagents to reduce reagent costs, the environmental burden of using such reagents, and the capital equipment needed to produce metals from MSWI ash. Simultaneously, this will introduce step-change capabilities in metal-selective extraction and refinement from MSWI ash. Preliminary analysis of MSWI ash shows modest amounts of valuable elements such as copper, manganese, zinc, and chrome. The proposed work constitutes molecule and formulation development, leaching experiments, and analytical work to determine the best conditions and lixiviants to leach valuable metals from MSWI ashes effectively. We will compare traditional chemical systems to our bio-inspired lixiviants and the total production cost of refined metals.