The urgency of developing new sources for critical minerals (CMS) led to the identification of acid mine drainage(AMD) as a potential source

This $200,000 Cooperative Agreement awarded by the U.S. Department of the Interior's Office of Surface Mining Reclamation and Enforcement (OSMRE) under the Science and Technology Projects Related to Coal Mining and Reclamation program (CFDA 15.255) aims to develop and demonstrate an integrated, pilot-scale solid-phase extraction process for the recovery of critical minerals from acid mine drainage (AMD). The project team at West Virginia University Research Corporation will fundamentally investigate the adsorption mechanisms of critical minerals on biochar sorbents, enhance the surface functionalities and pore structure of biochar for selective extraction, and develop an integrated process model to assess the technology's scalability and environmental advantages over traditional AMD treatment strategies. The work will leverage expertise in separation science, surface chemistry, biomass utilization, and process systems engineering to deliver a potentially transformative solution for extracting critical minerals from secondary sources and advancing sustainable AMD treatment.

Studies show abundance of CMS in AMD however, extracting them in an economicallyand environmentally viable manner remains challenging. Traditionally applied separation techniques (e.g.,leaching and solvent extraction) utilize environmentally problematic and expensive chemicals in large quantities, potentially introducing new waste to already polluted streams. The PIS aim at investigating a solid-phase biocharextraction process which is promising due to its high enrichment factor, rapid adsorption kinetics, decreasedsolvent consumption, and minimal waste generation. Biochar is an inexpensive and abundant sorbent with highsurface area, large pore volume, and stable structure having active pore surfaces for effective functionalizationand adsorption. Although biochar has been used to extract waterborne contaminants REF , its ability for selectiveextraction of ION species from a mixture of similar-sized and charged ions remains underutilized. According toprevious studies and our preliminary data, proper functionalization strategies could facilitate the selectiveextraction of desired species on biochar, and this forms the basis of this proposal. The project team willinvestigate how tuning biochars chemical and physical characteristicsfunctionalization controls and enhancesthe capacity and selectivity of biochar for extracting elements from AMD. Ultimately, this proposal targets todevelop, and demonstrate a solid-phase extraction process, as a potential carbon negative strategy, for thesustainable AMD treatment and extraction of CMS. The project team will fundamentally investigate the adsorptionmechanisms, and develop a process model for simulation and systems analysis, including economic and environmentalassessments for evaluating the technology potential for scalability. The PIS have already generated preliminary data showing that biochar sorbents have high capabilities to extractcms from diluted streams. The central hypothesis is that the active pore areas of biochar provide a large surfacecapable of accommodating CMS and facilitating a substantial reactional interface for various functionalities withaffinities towards certain ions and ionic compounds. The specific project objectives are: (1) enhance the surfacefunctionalities and pore structure of biochar for selective extraction of CMS and removal of impurities from AMD (2) develop an integrated, pilot-scale, solid-phase extraction process for the recovery of CMS from AMD followedby systematic field testing (3) develop an integrated process model for systems analysis towards technologyscalability (4) quantify the environmental advantages of the developed process over traditional AMD treatmentstrategies.to achieve the project objectives, the PIS will leverage resources from separation science, surface chemistry, biomass development and utilization, and process systems engineering. The team includes three departments at wvuand industry partners, allstar ecology and metzler forest products. Upon completing this project, we expect todevelop an integrated pilot-scale solid-phase extraction process with a potential positive impact in fields ofamd treatment and CMS extractions from secondary sources. Furthermore, the proposed works deliverables willbenefit the US, particularly coal communities in appalachia. Given the abundance of marginal agricultural andmined lands in appalachia region biomass production, the proposed biochar-based solid-phase extraction processpotentially generates another economic stream for this region.tracking