DESC0025168

The challenge of transitioning from fossil fuels to renewable energy sources underscores the urgent need for a sustainable and efficient approach to the extraction and refining of critical metals, such as lithium and rare earth elements, which are vital for the development of next-generation batteries and energy storage solutions. These metals are found in minerals extracted though pit mining, where large pits are excavated leading to significant environmental impacts, including habitat destruction, water pollution, and landscape alteration. These problems are then compounded in the subsequent refining process using high energy consumption, significant environmental degradation, and low efficiency, particularly when processing ores with minimal metal content. A novel approach utilizing biotechnology is being explored to eco-efficiently access domestic metal resources by developing specialized enzymes that break down metal-bearing silicate minerals, enabling the direct release of metal ions into aqueous solutions. This method, applicable in-situ within depleted oil wells, transforms them into sources of polymetallic brine, bypassing the need for conventional mining and refining processes. The project's overall objective is to engineer these enzymes for effective use in such subsurface environments, facilitating the sustainable and efficient recovery of critical metals from unconventional sources. This initiative seeks to lessen the environmental footprint of traditional extraction methods, diminish reliance on high-energy refinement processes and harmful chemicals, and improve the yield and diversity of extracted metals, marking a significant advancement towards a sustainable domestic critical metal supply for renewable energy technologies. In Phase I, the project team will (1) genetically engineer enzymes aimed at depolymerizing the phyllosilicate minerals in shales by using both standard molecular biology wet lab methods and an internal machine learning program that has been internally developed to optimize activity, substrate specificity (phyllosilicate clays), thermostability, solubility, E. coli expression, and pH, and then (2) develop by trial and error an optimal produced water composition to deliver the enzyme that retains its activity for in-situ application. (3) The operating conditions of the enzyme degradation reaction will then be identified and optimized to maximize metal recovery from the leachate solution at a 1-liter scale. The team will then (4) develop a comprehensive process for effectively removing residual hydrocarbons and impurities from the leach solution, while concurrently determining the most suitable metal recovery method. If successful, this will lead to a Phase II project with the aim of demonstrating this enzymatic metal extraction technology in a field trial in an old oil well. The solution provides a sustainable alternative to traditional mining, significantly reducing environmental impact, cutting costs, and bolstering domestic critical metal supply chains. It also transforms dormant oil fields into innovation and production hubs, spurring economic growth, job creation, and sustainable infrastructure development in these regions.