Grantee Research Project Results

Final Report: Precious Metal Recycling from Complex Solid Waste Using Highly Selective Porous Polymers

EPA Contract Number: 68HERC24C0022
Title: Precious Metal Recycling from Complex Solid Waste Using Highly Selective Porous Polymers
Investigators: Uliana, Adam
Small Business: ChemFinity Technologies, Inc
EPA Contact: Richards, April
Phase: I
Project Period: December 1, 2023 through May 30, 2024
Project Amount: $100,000
RFA: Small Business Innovation Research (SBIR) - Phase I (2024) RFA Text |  Recipients Lists
Research Category: Small Business Innovation Research (SBIR)

Description:

ChemFinity Technologies, Inc. conducted the project to evaluate the performance of their technology for recycling platinum group metals (PGMs) from catalytic converter waste. This innovative technology aims to streamline the recycling process by eliminating energy-intensive steps in traditional metal recycling processes. The project focused on three main objectives: establishing PGM leaching conditions for various waste grades, assessing metal extraction performance from the different waste grades, and evaluating PGM recovery and recycling from our selective porous polymers. ChemFinity’s porous polymers demonstrated significantly higher sorption capacities and selectivities for PGMs compared to commercial sorbents. Notably, the porous polymers achieved full extraction and desorption using a mild regeneration solvent, indicating their recyclability for multiple uses. The results also highlighted the exceptional stability of the porous polymers, with no degradation across various leaching conditions. These advancements position ChemFinity Technologies at the forefront of sustainable PGM recycling. The technology has potential for substantial commercial applications, promising significant reductions in energy consumption, CO₂ emissions, and water usage in PGM recycling, based on performance modeling of the technology. Future work will focus on scaling up the process, further optimizing recovery conditions, and developing full prototypes.

Summary/Accomplishments (Outputs/Outcomes):

From this project, we were first able to identify leaching conditions most effective for extracting platinum-group metals (PGMs) from various grades of catalytic converter waste. Additionally, our porous polymers demonstrated optimal performance under these conditions, surpassing the extraction efficiency (i.e., adsorption capacity and selectivity) of commercial sorbents. The porous polymers demonstrated ultrahigh selectivity for not only PGMs over competing base metals and other constituents, but also for separating individual PGMs from each other. The porous polymers also exhibited complete metal extraction and recovery using mild regeneration conditions, indicating potentially high recyclability without loss in performance. This exceptional performance under realistic leaching conditions further verifies the exceptional stability of the porous polymers, with no degradation observed. This supports a critical property for continued developments and commercial viability, compared to other emerging sorbent technologies. Overall, this project validated the exceptional extraction performance, stability, and recyclability of the porous polymers for PGM recycling from catalytic converter waste.

Conclusions:

The project demonstrated the high efficiency of the porous polymers in the recovery of PGMs from catalytic converter waste as a representative complex solid waste, surpassing incumbent commercial sorbents in sorption capacity and selectivity. Optimal leaching conditions were identified, facilitating maximum extraction and desorption of PGMs and thereby enhancing recovery rates. The use of the porous polymers significantly contributes to environmental sustainability by eliminating energy-intensive traditional methods in traditional recycling processes, reducing energy consumption, CO₂ emissions, and water usage. Economically, the technology proved cost-effective, with lower operational costs and high recovery efficiency, showing high promise for industrial applications. The porous polymers exhibited remarkable stability across various industrially used leaching conditions, ensuring longevity and reliability in repeated cycles. The technology achieved complete PGM extraction and desorption using a mild regeneration solvent.

The promising results indicate strong commercial potential, with modular scalability to meet industrial demands and the potential for broader applications in recovering other valuable metals. The reduced environmental impact of the porous polymer technology aligns with global sustainability goals and regulatory requirements. The ability to regenerate and reuse the porous polymers without performance loss enhances sustainability and cost-effectiveness, reducing the need for frequent material replacement. ChemFinity Technologies is strategically positioned to strongly impact the sustainable PGM recycling market, differentiating itself with innovative technology that supports the circular economy.

Future work will focus on optimizing recovery conditions, exploring scalability, and expanding the porous polymer applications to other metal recovery processes, such as recycling other metals from other waste sources (e.g., gold and rare earth elements from electronic waste; battery materials from spent batteries). The high tunability of the porous polymers shows promise for meeting these various applications. Collaborations with industry stakeholders and potential partners will be crucial for successful commercialization and implementation. ChemFinity Technologies remains committed to advancing sustainable practices in precious metal recycling, reducing the need for mining and aligning with its mission to reduce environmental impact while enhancing resource recovery and economic viability.