SYNTHETIC BIOLOGY APPROACH TO CRITICAL METAL EXTRACTION FROM WASTE ELECTRONIC COMPONENTS TO ENSURE A ROBUST SUPPLY OF CRITICAL MATERIALS FOR CLEAN ENERGY

Most end-of-life electronics (e-waste) end up in landfills where it causes serious environmental problems. While the glass and metals in e-waste components can be recycled, conventional extraction methods rely on energy-intensive processes that are inefficient and expensive when applied to e-waste that contains mixed materials and small amounts of metals. To make e-waste recycling economically viable and competitive with obtaining raw materials from mining, we are developing a biological recovery platform that provides energy-efficient metal reclamation and minimizes environmental impact. Our service is to provide a secure supply chain of critical metals. We do this by offering closed-loop recycling through our biological platform for metal recovery from e-waste. This innovative platform uses biological functions to efficiently extract, concentrate, and purify metals from e-waste and is also applicable to low-grade mineral ores. At present, no genetically modified organisms are being used in commercial scale biomining. The use of engineered microbes could provide significant benefits to traditional biomining. For example, increasing tolerance to fluctuating and challenging process conditions reduces the time required for metal extraction. We use the full spectrum of synthetic biology tools available for the development of novel microbes and metabolic pathways for biomining microorganisms. Our customers are tech hardware manufacturers that need a stable source of critical metals for their products and seek to generate less waste. The customer needs and market pain points are supply chain instabilities from geopolitical factors; thus, the goal is to have a closed-loop metal lifecycle to reclaim and reuse the limited resources (metals) in their products. The key differentiator is that we offer a biological alternative to traditional mining that does not have the intensive energy requirements of traditional smelting and refining methods. The potential societal value of the innovation is that critical metals are recovered from components that would otherwise end up in landfills,pollute soils and water, and not recycled. We are developing a platform that that allows for energy-efficient elemental recovery and is a fundamental change to how e-waste is managed and processed. The innovation uses synthetic biology to efficiently extract, concentrate, and purify critical and strategic elements from mineral process streams, ore, acid mine drainage, and e-waste. The proposed work begins by focusing on electronic components that contain 1) critical metals (Ga, Al, In, Sn, Ta, REEs) doped in a silicate (Si) matrix, such as phone screens, ceramic capacitors, catalysts, etc., and 2) iron (Fe)-rich components such as permanent and rare earth magnets containing REEs (Pr, Nd, Dy). While bioleaching is an established method for metal recovery (Cu, Au) for sulfide minerals, we are not proposing bioleaching with traditional substrates. We propose a transformative biotechnology that will recover critical metals from previously uneconomical wastes. For Fe-rich substrates, liberation of REEs is accomplished via accelerated weathering using engineered biomining microorganisms that are optimized for targeted metal recovery. Additionally, critical metals contained in a Si-rich matrix are released by active depolymerization of the silicate matrix that is catalyzed by an optimized enzymatic process. There is no current approach in materials recycling that uses enzymatic dissolution or accelerated weathering using engineered microorganisms to remove the metal-containing matrix from waste electronics or other substrates. The goal of this first “pre-treatment” stage is to liberate critical metals from the matrix for downstream recovery from effluent using functionalized bio-derived membranes containing bioengineered peptides that selectively filter metals of interest.