North Dakota is a significant contributor to U.S. soybean production. According to the USDA, the state harvested approximately 6.2 million acres of soybeans, yielding more than 220 million bushels. An abundance of soybean hulls can be utilized for sustainable waste management and to deliver economic benefits for the region. To date, soy-based materials have found applications in production of tires, biodiesel production, food and feed industries, and the development of environmentally friendly adhesives, plastics, and coatings. Therefore, these innovations highlight the versatility of soy-based products in reducing the environmental footprint of various manufacturing processes. Beyond these uses, soybean hulls present an untapped potential for advanced applications, such as serving as alternative adsorbents for emerging contaminants with an adsorption process. Though soybean-based activated carbon has been tested in laboratory-scale experiments for a limited number of organic and inorganic contaminants, its application in removing recently regulated carcinogenic PFAS compounds has not been studied before. Therefore, its commercial value has not yet been well understood for removing PFAS chemicals and beyond. Soybean hull-based activated carbon offers unique properties, such as a high surface area (up to ~2800 m²/g), high surface charge (up to ~10.5), and high micropore volume (up to 80%) which may provide a higher adsorption capacity for PFAS compounds compared to commercially available lignite based activated carbons. PFAS chemicals have been used in thousands of everyday products, which have been proven to be toxic and are therefore classified as emerging contaminants. These human-made chemicals are characterized by their remarkable stability, unique surfactant properties, oil and water repellency, and exceptional chemical resistance. While these attributes have made PFAS valuable in applications such as non-stick cookware, water-resistant fabrics, firefighting foams, and food packaging, they also render these substances highly persistent in the environment. Their persistence and mobility in aquatic and terrestrial systems have been linked to significant adverse health effects, including developmental issues, hormonal disruptions, immune system impairments, and increased risk of certain cancers. As a result, PFAS contamination presents a growing challenge to environmental management and public health, necessitating the development of efficient and cost-effective remediation technologies to mitigate their occurrence in the environment. According to previous reports, soybean hulls can be produced at a cost approximately 0.08 USD/kg, which is substantially lower than the average production cost of commercial activated carbon adsorbents of >3 USD/kg. From both techno-economic and sustainability perspectives, soybean hulls can be used as an alternative adsorbent in removing PFAS from potable water systems. Therefore, there is an urgent need for thorough and systematic study to investigate the adsorption efficiency of PFAS by soybean hull-based adsorbents. Comparative assessments of these materials against alternative adsorbents are crucial, with key metrics including adsorption capacity, regeneration efficiency, and affinity for PFAS of varying chain lengths (short- vs. long-chain) in varying background matrices. By developing a value-added product from waste soybean hulls, this proposed study will primarily focus on aspects that expand the use of this waste product, thereby enhancing the overall profitability of soybean growers. Leveraging this renewable resource could further strengthen North Dakota's position as a leader in sustainable agricultural and industrial practices.

The main objectives of this study are to: i) prepare two types of high-capacity soybean based activated carbon: pristine (non-metal doped) and magnetically enabled (iron doped) from
waste soybean hulls, ii) evaluate the PFAS removal efficiencies of the prepared soybean based activated carbons against commercially available activated carbons, and iii) identify the factors
(e.g., PFAS type, activated carbon characteristics, water quality) influencing the removal of PFAS compounds from surface water sources and wastewater effluents.

To effectively communicate research findings to North Dakota soybean growers, the results will be disseminated through multiple channels. The North Dakota Soybean Council (NDSC) publishes annual research updates that can include findings from this project. Findings will be disseminated via NDSC committee meetings, regional (Red River Valley Conference, North Dakota Water and Pollution Control Conference) and national (American Water Works Association’s Annual Conference & Expo [AWWA-ACE], or Water Quality and Technology Conference [WQTC]) conferences, peer-reviewed publications, and direct communication to soybean growers. The project team will develop general demonstration BrainSTEM activities held at the University of North Dakota (UND) to showcase the technology’s benefits to K-12 students and a general audience.

This research will investigate an innovative and sustainable way to add value to soybean hulls, an underutilized byproduct, potentially creating a new revenue stream for North Dakota soybean farmers, while promoting environmental sustainability and enhancing the state's leadership in agricultural innovation. The proposed soybean hull based activated carbons will provide 2-3x higher capacity to remove PFAS from contaminated waters within the state to comply with the recent PFAS regulations. This will reduce the dependence on the commercially available activated carbon which is sourced from other states or imported from other countries. The development of high-capacity soybean hull-based activated carbon for PFAS removal directly benefits farmers by enhancing profitability, promoting sustainable practices, and positioning North Dakota as a key player in emerging markets for eco-friendly materials, all while contributing to the region’s overall economic growth.